Visceral Structures of the Thorax - Arranged Alphabetically
|
| Organ/Part of Organ |
Location/Description |
Notes |
| apex |
tip of the left ventricle of the heart |
apex of the heart is located 3" to the left of the midline at the level
of the 5th intercostal space |
| atrioventricular bundle |
part of the conduction system of the heart |
atrioventricular bundle is a strand of specialized myocardium that passes
through the right fibrous trigone into the muscular part of the interventricular
septum; it divides into right and left branches to supply the ventricles; also
known as: bundle of His |
| atrioventricular node |
part of the conduction system of the heart |
atrioventricular node is located in the wall of the right atrium above the
opening of the coronary sinus and the septal cusp of the tricuspid valve |
| atrioventricular valve, left |
heart valve located between the left atrium and the left ventricle |
left atrioventricular valve has two valve cusps; also known as: mitral or
bicuspid valve |
| atrioventricular valve, right |
atrioventricular node between the right atrium and the right ventricle |
right atrioventricular valve has three valve cusps; also known as: tricuspid
valve |
| atrium, right |
chamber of the heart that receives deoxygenated blood from the systemic
circulation (body) |
right atrium forms the right margin of the heart; it receives blood from the superior vena cava, inferior vena cava and coronary sinus (Latin, atrium = an entrance hall) |
| atrium, left |
chamber of the heart that receives oxygenated blood from the pulmonic circulation
(lungs) |
left atrium is located on the posterior aspect of the heart; it receives blood from the pulmonary vv. (Latin, atrium = an entrance hall) |
| auricle |
small appendage that projects anteriorly from the atrium |
paired, one on each atrium; right auricle lies beside the aorta and covers the right coronary artery; left auricle lies beside the pulmonary trunk (Latin, auricle = little ear, the auricle of the atrium is shaped like a little ear) |
| base |
the superior aspect of heart |
base of the heart is where the aorta, pulmonary trunk and superior vena
cava exit/enter the heart |
| bronchi |
the air conducting passages of the lungs |
bronchi may be classified as primary, secondary (lobar), and tertiary (segmental) |
| bronchus, primary |
first branch of the air conducting system arising from the bifurcation of
the trachea at T4/T5 intervertebral disc |
paired, right and left; one primary bronchus enters the hilus of each lung; the right primary bronchus is shorter, larger in diameter and more vertically oriented than the left so that aspirated foreign bodies tend to lodge in the right primary bronchus (Latin/Greek, bronchos = windpipe) |
| bronchus, secondary |
a branch of the air conducting system arising from the primary bronchus |
there are 3 secondary bronchi in the right lung: upper, middle, lower; there are 2 secondary bronchi in the left lung: upper, lower; also known as: lobar bronchi (Latin/Greek, bronchos = windpipe) |
| bronchus, tertiary |
a branch of the air conducting system arising from the secondary (lobar)
bronchus |
there are 10 tertiary bronchi in the right lung: branching from the right superior lobar bronchus - apical, anterior, posterior; branching from the right middle lobar bronchus - medial, lateral; branching from the right inferior lobar bronchus - superior, anterior basal, posterior basal, medial basal, lateral basal; there are 8 tertiary bronchi in the left lung: branching from the left superior lobar bronchus - apicoposterior, anterior; branching from the lingular bronchus (off of the superior lobar bronchus) - superior lingular, inferior lingular; branching from the inferior lobar bronchus - superior, anteromedial basal, posterior basal, lateral basal; also known as: segmental bronchi (Latin/Greek, bronchos = windpipe) |
| bronchus, segmental |
a branch of the air conducting system arising from the secondary (lobar)
bronchus |
there are 10 tertiary bronchi in the right lung: branching from the right superior lobar bronchus - apical, anterior, posterior; branching from the right middle lobar bronchus - medial, lateral; branching from the right inferior lobar bronchus - superior, anterior basal, posterior basal, medial basal, lateral basal; there are 8 tertiary bronchi in the left lung: branching from the left superior lobar bronchus - apicoposterior, anterior; branching from the lingular bronchus (off of the superior lobar bronchus) - superior lingular, inferior lingular; branching from the inferior lobar bronchus - superior, anteromedial basal, posterior basal, lateral basal; also known as: segmental bronchi (Latin/Greek, bronchos = windpipe) |
| carina |
keel-shaped cartilage lying within the tracheal bifurcation |
carina trachealis is an important landmark during endoscopy of the bronchial tree (Latin, carina = the keel of a boat) |
| chordae tendineae |
thin connective tissue cords that attach the atrioventricular valve cusps
to the papillary mm. |
chordae tendineae are found only in the ventricles, not in the atria |
| coronary sulcus |
groove on the surface of the heart that separates the atria from the ventricles |
coronary sulcus contains the coronary sinus, circumflex a., and right coronary a. (Latin, coronary = crown + sulcus = a furrow or ditch) |
| crista terminalis |
ridge of cardiac muscle separating the smooth sinus venarum posteriorly
from the roughened wall of the primitive atrium anteriorly |
the sinuatrial node lies within the superior end of the crista terminalis (Latin, crista = crest) |
| cupula |
serous membrane lining the pleural cavity which extends above the level
of the 1st rib into the root of the neck |
cupular pleura is continuous inferiorly with the costal and mediastinal
parietal pleurae; it is reinforced by a specialization of scalene fascia (called
Sibson's fascia or suprapleural membrane); also known as: cervical parietal
pleura or cervical dome of pleura |
| esophagus |
the portion of the gastrointestinal tract between the pharynx and the stomach |
connects: superiorly with laryngopharynx at lower border of cricoid cartilage;
inferiorly it passes through diaphragm at the T10 vertebral level to reach
the stomach; the upper 1/3 is skeletal muscle innervated by the recurrent laryngeal,
the lower 2/3rds is smooth muscle innervated by the vagus nn. via the esophageal
plexus |
| fissure, oblique |
deep groove in the surface of the lung that separates the upper lobe from
the lower lobe (both lungs), and the middle lobe from the lower lobe (right
lung) |
oblique fissure extends from the level of the T3 vertebra posteriorly to
the 6th costochondral junction anteriorly |
| fissure, horizontal |
deep groove in the surface of the lung that separates the middle lobe from
the upper lobe (right lung only) |
horizontal fissure extends from the 5th rib at the mid-axillary line along
the 4th rib to the sternum anteriorly |
| fossa ovalis |
shallow depression in the left wall of the right atrium |
fossa ovalis is the remnant of the foramen ovale which provided an open communication between the right atrium and left atrium in the fetus |
| heart |
muscular pump for blood located within middle mediastinum of the thorax |
heart is nearly surrounded by the pericardial sac and pericardial cavity |
| interventricular sulcus, anterior |
groove between the ventricles on the anterior surface of the heart |
anterior interventricular sulcus contains the anterior interventricular
a. and the great cardiac v.; it marks the location of the interventricular
septum |
| interventricular sulcus, posterior |
groove between the ventricles on the diaphragmatic surface of the heart |
posterior interventricular sulcus contains the posterior interventricular
a. and the middle cardiac v.; it marks the location of the interventricular
septum |
| ligamentum arteriosum |
fibrous cord of connective tissue that connects the left pulmonary a. near
its origin with the undersurface of the aortic arch |
ligamentum arteriosum is a remnant of the ductus arteriosus; the left recurrent
laryngeal n. passes beneath it |
| limbus fossa ovalis |
the ridge around the fossa ovalis in the left wall of the right atrium |
limbus fossa ovalis is the margin of the septum primum (Latin, limbus = a border + fossa = a trench + ovalis = oval) |
| lobe, inferior |
the portion of the lung supplied by the inferior lobar bronchus |
inferior lobe of the right lung: possesses 5 bronchopulmonary segments -
superior, anterior basal, posterior basal, medial basal, lateral basal; inferior
lobe of the left lung: possesses 4 bronchopulmonary segments - superior, anteromedial
basal, posterior basal, lateral basal |
| lobe, middle |
the portion of the right lung supplied by the middle lobar bronchus |
middle lobe is found in the right lung only; it possesses 2 bronchopulmonary
segments: medial and lateral; lingula of the inferior lobe of the left lung
is equivalent to the middle lobe of the right lung |
| lobe, superior |
the portion of the lung supplied by the superior lobar bronchus |
superior lobe of the right lung: possesses three bronchopulmonary segments
- apical, anterior and posterior; superior lobe of the left lung: possesses
four bronchopulmonary segments - apicoposterior, anterior, superior lingular,
inferior lingular |
| lung |
the portion of the respiratory system where exchange of gasses occurs between
the air and the blood; located in the thoracic cavity |
paired; right lung is divided into three lobes: superior, middle and inferior;
left lung has two lobes: superior and inferior |
| mitral valve |
heart valve located between the left atrium and the left ventricle |
mitral valve has two valve cusps; it is named for the similarity of its
shape to that of a bishop's miter; also known as: left atrioventricular valve
or bicuspid valve |
| moderator band |
ridge of cardiac muscle spanning from the interventricular septum to the
anterior papillary m. in the right ventricle |
septomarginal trabecula contains part of the right branch of the atrioventricular
bundle; also known as: septomarginal trabecula |
| papillary muscle |
a small, nipple-like projection of cardiac muscle located within the ventricles |
papillary muscles attach to the cusps of the atrioventricular valves via
chordae tendineae and act to keep the valve cusps from prolapsing under systolic
blood pressure; there are three in the right atrium: anterior, posterior, septal;
there are two in the left atrium: anterior, posterior |
| pectinate muscles |
prominent ridges of myocardium located on the inner surface of the right
atrium |
pectinate muscles are very pronounced in the right atrium and in both auricles |
| pericardial sinus, oblique |
an area of the pericardial cavity located behind the left atrium of heart |
serous pericardium reflects onto the inferior vena cava and pulmonary vv.
to define this space |
| pericardial sinus, transverse |
an area of the pericardial cavity located behind the aorta and pulmonary
trunk and anterior to the superior vena cava |
transverse pericardial sinus was a simple structure when the heart tube
began to form during development; it separates the outflow vessels from the
inflow vessels of the heart |
| pericardium, fibrous |
a fibrous sac that attaches to the central tendon of the diaphragm and fuses
with the adventitia of the great vessels superiorly |
fibrous pericardium contains the pericardial cavity and heart; it is lined
on its inner surface by the parietal layer of serous pericardium; it defines
the outermost boundary of the middle mediastinum |
| pericardium, parietal serous |
serous membrane lining the pericardial cavity; it is located on the inner
surface of the fibrous pericardium |
parietal serous pericardium reflects onto the heart at the origins of the
great vessels to become continuous with the visceral serous pericardium |
| pericardium, visceral serous |
serous membrane covering the surface of the heart |
visceral serous pericardium reflects onto the inner surface of the fibrous
pericardium at the origins of the great vessels to become continuous with the
parietal serous pericardium; also known as: epicardium |
| pleura |
serous membrane lining the pleural cavity |
there are two types of pleura: visceral pleura covers the lungs, parietal pleura lines the inner surfaces of the walls of pleural cavity; parietal pleura is sensitive to pain but visceral pleura is not sensitive to pain (Greek, pleura = a rib) |
| pleura, cervical parietal |
serous membrane lining the pleural cavity which extends above the level
of the 1st rib into the root of the neck |
cervical parietal pleura is continuous inferiorly with the costal and mediastinal parietal pleurae; it is reinforced by a specialization of scalene fascia (called Sibson's fascia or suprapleural membrane); also known as: cupula or cervical dome of pleura (Greek, pleura = a rib) |
| pleura, costal parietal |
serous membrane lining the pleural cavity on the inner surfaces of the ribs,
costal cartilages, and intercostal mm. |
costal parietal pleura is continuous anteriorly with the mediastinal parietal pleura at the costomediastinal reflection; it is continuous posteriorly with the mediastinal parietal pleural at the vertebral bodies; it is continuous inferiorly with the diaphragmatic parietal pleura at the costodiaphragmatic reflection; it is continuous superiorly with the cervical parietal pleura at the level of the 1st rib (Greek, pleura = a rib) |
| pleura, diaphragmatic parietal |
serous membrane lining the pleural cavity on the superior surface of the
diaphragm |
diaphragmatic parietal pleura is continuous superiorly with the costal parietal
pleura at the costodiaphragmatic reflection; it is continuous superiorly with
the mediastinal pleura at the inferomedial borders of the pleural cavities |
| pleura, mediastinal parietal |
serous membrane lining the pleural cavity on the lateral surface of the
mediastinum |
mediastinal parietal pleura is continuous anteriorly with the costal parietal
pleura at the costomediastinal reflection; it is continuous inferiorly with
the diaphragmatic pleura at the inferomedial borders of the pleural cavities;
it is continuous posteriorly with the costal parietal pleura lateral to the
vertebral bodies; it is continuous superiorly with the cervical pleura at the
level of the 1st rib |
| pleura, visceral |
serous membrane lining the surfaces of the lungs |
visceral pleura extends into the oblique and horizontal fissures of the
lungs; it does not have pain fibers |
| pulmonary conus |
smooth area of the right ventricle below the opening into the pulmonary
trunk |
pulmonary conus is the pulmonary part of the conus cordis which divides during development to form the outflow portions of the right and left ventricles (Latin, conus = cone) |
| pulmonary ligament |
fold of pleura located below the root of the lung |
pulmonary ligament is where the visceral pleura and the mediastinal parietal
pleura are continuous with each other |
| semilunar valves |
valve with three pocket-shaped cusps located in the base of the pulmonary
trunk and ascending aorta |
semilunar valve has a thin endothelial free margin on each cusp called a lunula; a dense nodule is located at the midpoint of the free margin of each valve cusp; the pulmonary semilunar valve has anterior, left and right cusps; the aortic semilunar valve has right, left and posterior cusps (Latin, semis = half + luna = moon, the cusps of semilunar valves are shaped like a half moon) |
| septomarginal trabecula |
ridge of cardiac muscle spanning from the interventricular septum to the
anterior papillary m. in the right ventricle |
septomarginal trabecula contains part of the right branch of the atrioventricular bundle; also known as: moderator band |
| sinuatrial node |
part of the conduction system of the heart |
sinuatrial node is located within the crista terminalis near the superior
vena cava; it is the "pacemaker" of the heart |
| sulcus terminalis |
groove on the external surface of the right atrium marking the location
of the crista terminalis |
the sinuatrial node is located at the superior end of the crista terminalis (Latin, sulcus = a furrow or ditch) |
| trabeculae carnae |
ridges of cardiac muscle located on the inner wall of both ventricles |
(Latin, trabecula from the word trabs = a beam) |
| trachea |
main airway that lies anterior to the esophagus |
trachea extends from vertebral level C6 to the level of the T4/5 intervertebral
disc; superiorly it is connected to the cricoid cartilage via the cricotracheal
ligament; it bifurcates into two primary bronchi |
| tricuspid valve |
a three cusped valve located at the ostium between the right atrium and
the right ventricle |
tricuspid valve possesses anterior, posterior and septal cusps; also known
as: right atrioventricular valve |
| ventricle, right |
heart chamber that pumps blood to the pulmonary circulation |
right ventricle has a septomarginal trabecula and 3 papillary mm.; it pumps
blood into the pulmonary trunk |
| ventricle, left |
heart chamber that pumps blood to the systemic circulation |
left ventricle has 2 papillary mm.; it pumps blood into the ascending aorta |
Visceral Structures of the Abdomen - Arranged Alphabetically
|
| Organ/Part of Organ |
Location/Description |
Notes |
| adrenal gland |
endocrine gland located superomedial to the kidney; right adrenal gland
is somewhat triangular in shape, left is semilunar in shape |
adrenal cortex manufactures corticosteroids; adrenal medulla manufactures epinephrine and norepinephrine; adrenal medulla receives preganglionic sympathetic innervation from the greater thoracic splanchnic n.; also known as: suprarenal gland (Latin, ad = to or towards + renal = kidney) |
| angular notch of the stomach |
a sharp indentation located about 2/3 of the way down the lesser curvature
of the stomach |
angular notch marks the transition from body of stomach to pylorus |
| appendix, vermiform |
terminal portion of the cecum which has a small dead-end lumen |
vermiform appendix is attached to the posteroinferior surface of the cecum; it is usually located behind the cecum in the right iliac fossa; pain from the appendix projects to McBurney's point on anterior abdominal wall (1/3rd distance along and imaginary line from the anterior superior iliac spine to the umbilicus); it has a complete peritoneal covering and a small mesentery (mesoappendix) |
| appendix epiploica |
fat-filled pendants of peritoneum projecting from the visceral peritoneum
on the surface of the large intestine |
there are many appendices epiploices on the large intestine (except the
rectum) and none on the small intestine; also known as: omental appendage |
| ascending colon |
part of the large intestine that is continuous with the cecum proximally
and the transverse colon at the right colic (hepatic) flexure |
ascending colon is retroperitoneal |
| bare area of the liver |
the part of the diaphragmatic surface of the liver that is not covered by
visceral peritoneum |
bare area is between the anterior and posterior laminae of the coronary
ligament and is in contact with the diaphragm |
| bile duct, common |
part of the biliary tree that is formed by the union of the cystic and common
hepatic ducts; located in the hepatoduodenal ligament |
common bile duct drains into the hepatopancreatic ampulla and greater duodenal
papilla in company with the main pancreatic duct |
| calyx, minor |
portion of the urinary collecting system within the kidney that drains one
renal papilla |
one renal papilla projects into the lumen of one minor calyx; several minor calyces unite to form a major calyx (Greek, calyx = cup (of a flower)) |
| calyx, major |
portion of the urinary collecting system within the kidney that drains several
minor calyces |
major calyx collects urine from several renal papillae; all major calyces unite to form the renal pelvis (Greek, calyx = cup (of a flower)) |
| cardia of the stomach |
part of the stomach surrounding the opening of the esophagus |
esophagus empties into the stomach at this location; also known as: cardiac region of the stomach (Greek, cardia = heart) |
| caudate lobe |
tail-like projection of the liver |
caudate lobe arises from the posterior aspect of liver to the left of the inferior vena cava; functionally it is part of both the right and left lobes of liver |
| cecum |
first part of the large intestine which is located in the right lower quadrant |
cecum is continuous with the ileum (small intestine) at the ileocecal valve; it is continuous with the ascending colon distally; it is intraperitoneal but lacks a mesentery; the vermiform appendix is attached to its posteroinferior surface (Latin, cecum = blind) |
| coronary ligament |
peritoneum connecting the liver to the inferior surface of the diaphragm |
it has three parts which together form a complete circle: right triangular ligament, left triangular ligament, falciform ligament; area between the anterior and posterior laminae of the coronary ligament is called the bare area of the liver (Latin, coronary = crown) |
| cystic duct |
duct of the gallbladder |
cystic duct joins with the common hepatic duct to form the common bile duct;
cystic duct both fills and drains the gallbladder |
| descending colon |
part of the large intestine that is continuous with the transverse colon
at the left colic (splenic) flexure and the sigmoid colon at the pelvic brim |
descending colon is retroperitoneal |
| duodenojejunal junction |
part of the small intestine where the duodenum is continuous with the jejunum |
duodenojejunal junction is located in the left upper quadrant; it is suspended
by the suspensory muscle (ligament) of the duodenum; the inferior mesenteric
v. passes to left side of the duodenojejunal junction |
| duodenum |
proximal segment of the small intestine |
C-shaped; the duodenum has 4 parts: 1st or superior, 2nd or descending,
3rd or transverse, 4th or ascending |
| epiploic foramen |
passageway between the greater peritoneal sac and the lesser peritoneal
sac |
located posterior to the hepatoduodenal ligament; also known as: omental
foramen |
| esophagus |
the portion of the gastrointestinal tract between the pharynx and the stomach |
connects: superiorly with laryngopharynx at lower border of cricoid cartilage;
inferiorly it passes through diaphragm at the T10 vertebral level to reach
the stomach; the upper 1/3 is skeletal muscle innervated by the recurrent laryngeal,
the lower 2/3rds is smooth muscle innervated by the vagus nn. via the esophageal
plexus |
| falciform ligament |
sickle-shaped fold of peritoneum connecting the liver to the umbilicus |
falciform ligament contains the round ligament of the liver (ligament teres hepatis); it is a remnant of the ventral mesogastrium of the embryo (Latin, falciform = sickle-shaped) |
| gallbladder |
diverticulum of the biliary tract that hangs below the liver between the
right and quadrate lobes |
located in the right upper quadrant; gallbladder is connected to the common
bile duct via the cystic duct; it both stores and concentrates bile; pain from
the gallbladder may be referred to the right shoulder |
| gallbladder, body of |
the main part of the gallbladder |
body of the gallbladder lies in the bed of the gallbladder, between the
right and quadrate lobes of the liver |
| gallbladder, fundus of |
expanded inferior part of the gallbladder |
fundus of the gallbladder is located near the inner surface of the anterior
abdominal wall at the junction of the right 9th costal cartilage and the right
semilunar line; it normally hangs below the margin of the liver |
| gallbladder, neck of |
constricted superior part of the gallbladder |
neck of the gallbladder is the portion that connects the body of the gallbladder
to the cystic duct; it contains a spiral fold |
| gastric folds |
folds of the mucosal lining of the stomach |
gastric folds are ridges that generally run from the cardia of the stomach
toward the pyloris along the lesser curvature; also known as: rugae |
| gastrocolic ligament |
peritoneum connecting the greater curvature of the stomach with the transverse
colon |
part of the greater omentum; derived from the dorsal mesogastrium in the
embryo |
| gastrolienal ligament |
peritoneum connecting the greater curvature of stomach with the hilum of
the spleen |
part of the greater omentum; derived from the dorsal mesogastrium in the
embryo; also known as: gastrosplenic ligament |
| gastrophrenic ligament |
peritoneum connecting the fundus of the stomach to the left side of the
diaphragm above the spleen |
part of the greater omentum; derived from the dorsal mesogastrium in the embryo (Greek, phrenic = diaphragm) |
| gastrosplenic ligament |
peritoneum connecting the greater curvature of stomach with the hilum of
the spleen |
part of the greater omentum; derived from the dorsal mesogastrium in the embryo; also known as: gastrolienal ligament |
| greater duodenal papilla |
nipple-like projection into the 2nd part of the duodenum |
greater duodenal papilla is the site of drainage of the common bile duct and main pancreatic duct (Latin, papilla = nipple or pimple) |
| greater omentum |
apron-like specialization of peritoneum attaching along the greater curvature
of the stomach |
subdivisions: gastrophrenic ligament, gastrosplenic ligament, gastrocolic
ligament, omental apron |
| greater peritoneal sac |
the portion of the peritoneal cavity that is not located posterior to the
stomach |
the lesser peritoneal sac is the only part of the peritoneal cavity that
is not part of the greater peritoneal sac |
| haustra |
multiple pouches in the wall of the large intestine |
haustra form where the longitudinal muscle layer of the wall of the large intestine is deficient; also known as: sacculations (Latin, haustra = a machine for drawing water) |
| hepatic duct, common |
duct formed by the joining of the of right and left hepatic ducts |
common hepatic duct unites with the cystic duct to form the common bile
duct |
| hepatic duct, left |
duct that drains the left lobe of the liver, quadrate lobe and part of the
caudate lobe of the liver |
left hepatic duct joins with right hepatic duct to form the common hepatic
duct |
| hepatic duct, right |
duct that drains the right lobe of the liver and part of the caudate lobe
of the liver |
right hepatic duct joins with the left hepatic duct to form the common hepatic
duct |
| hepatic flexure |
junction of the ascending colon and the transverse colon |
hepatic flexure lies anterior to the lower part of the right kidney and
inferior to the right lobe of the liver; also known as: right colic flexure |
| hepatoduodenal ligament |
part of the lesser omentum connecting the liver to the 1st part of duodenum |
hepatoduodenal ligament contains the common bile duct, proper hepatic a.
and portal v.; it forms the anterior wall of the omental (epiploic) foramen |
| hepatogastric ligament |
part of the lesser omentum connecting the liver to the lesser curvature
of the stomach |
hepatogastric ligament forms the anterior wall of the lesser peritoneal
sac |
| hepatopancreatic ampulla |
union of the common bile duct and the main pancreatic duct |
hepatopancreatic ampulla opens onto the greater duodenal papilla in the 2nd part of the duodenum (Latin, ampulla = a two-handed bottle) |
| ileocecal junction |
point at which the ileum joins the cecum |
ileocecal valve moderates the flow of intestinal contents from the ileum
into the cecum |
| ileocecal valve |
a valve that marks the ileocecal junction |
ileocecal valve is incompetent, not a sphincter; it has superior and inferior
lips |
| ileum |
most distal part of the small intestine |
ileum is continuous with the jejunum proximally and terminates at ileocecal junction distally; it is approximately 12 feet in length; it has a thinner wall than the jejunum, lower plicae circulares than the jejunum, more fat in its mesentery than does the jejunum, more complex arterial arcades than the jejunum, shorter arteriae recta than the jejunum (Greek, ileum derived from eileos = twisted) |
| intestine, large |
part of the intestinal tract distal to the small intestine |
large intestine is approximately 5 feet long; parts of the large intestine
are: cecum, ascending colon, transverse colon, descending colon, sigmoid colon,
rectum; also known as: colon or large bowel |
| intestine, small |
part of the small intestine between the stomach proximally and the large
intestine distally |
small intestine is approximately 21 feet long; parts of the small intestine
are: duodenum (1 foot long, mostly retroperitoneal); jejunum (8 feet long);
ileum (12 feet long) |
| jejunum |
part of the small intestine that is continuous with the duodenum proximally
(at the duodenojejunal junction) and the ileum distally (no obvious landmark
for its termination) |
jejunum is approximately 8 feet in length; wall of the jejunum is thicker than the wall of the ileum; plicae circulares (circular folds) are more pronounced in the jejunum than in the ileum; mesentery of the jejunum has less fat than that of the ileum; arterial arcades of the jejunum are more simple than those of the ileum; arteriae recta are longer in the jejunum than they are in the ileum (Latin, jejunum = empty, for it was noted to be empty after death) |
| kidney |
excretory organ of the urinary tract located on the posterior abdominal
wall |
retroperitoneal; right kidney is lower than the left - its superior pole
reaches the 12th rib; superior pole of the left kidney reaches as high as the
11th rib; kidneys develop from the intermediate mesoderm in the embryo |
| lateral inguinal fossa |
shallow depression on the inner aspect of the abdominal wall lateral to
the lateral umbilical fold |
an indirect inguinal hernia passes through the anterior abdominal wall in this fossa |
| lateral umbilical fold |
peritoneal fold overlying the inferior epigastric vessels |
an indirect inguinal hernia passes through the anterior abdominal wall lateral
to this fold; a direct inguinal hernia passes through the anterior abdominal
wall medial to this fold |
| left colic flexure |
junction of the transverse colon and descending colon |
left colic flexure lies anterior to the left kidney and inferior to the
spleen; also known as: splenic flexure |
| lesser duodenal papilla |
nipple-like projection into the 2nd part of the duodenum superior to the
greater duodenal ampulla |
lesser duodenal papilla is the site of drainage of the accessory pancreatic
duct |
| lesser omentum |
peritoneum stretching between the lesser curvature of the stomach and the
visceral surface of the liver |
subdivisions of the lesser omentum are the heptogastric and hepatoduodenal
ligaments; lesser peritoneal sac (omental bursa) lies posterior to the lesser
omentum and stomach |
| lesser peritoneal sac |
part of the peritoneal cavity located posterior to the stomach and lesser
omentum |
lesser peritoneal sac is continuous with the greater peritoneal sac at the
omental (epiploic) foramen; also known as: omental bursa |
| lienorenal ligament |
peritoneum that attaches the spleen to the posterior abdominal wall over
the left kidney
| lienorenal ligament develops from the dorsal mesogastrium of the embryo;
also known as: splenorenal ligament |
| ligamentum teres hepatis |
cord-like ligament that lies within the free margin of the falciform ligament |
ligamentum teres hepatis courses from the liver to the umbilicus; it is the remnant of the umbilical v.; also known as: round ligament of liver (Latin, teres = round) |
| ligamentum venosum |
cord-like ligament that lies within the attachment of the hepatogastric
ligament to the liver, between the caudate lobe and the left lobe |
ligamentum venosum is a remnant of the obliterated ductus venosus which
shunted oxygenated blood from the placenta around the liver to the inferior
vena cava during development |
| liver |
largest digestive organ in the body, located mostly in the right upper quadrant |
the liver consists of 4 anatomical lobes: left, right, quadrate and caudate;
it lies inferior to the diaphragm and rises as high as the 5th rib on the right
side; liver functions include: synthesis, storage and release of glycogen and
vitamins; synthesis of blood proteins; phagocytosis of old red blood cells;
removal of toxic substances |
| medial inguinal fossa |
shallow depression on the inner aspect of the abdominal wall between the
medial inguinal fold and the lateral umbilical fold |
a direct inguinal hernia passes through the anterior abdominal wall in this
fossa; it passes through a subdivision called the inguinal triangle |
| medial umbilical fold |
peritoneal fold overlying the medial umbilical ligament |
medial umbilical ligament is the obliterated umbilical a. |
| median umbilical fold |
peritoneal fold overlying the median umbilical ligament (remnant of urachus) |
median umbilical ligament is the remnant of the urachus |
| mesentery |
peritoneum connecting jejunum & ileum to posterior abdominal wall |
also known as: mesentery of small intestine |
| mesoappendix |
peritoneum connecting the vermiform appendix to the mesentery of the small
intestine |
the cecum is retroperitoneal, but the appendix has its own mesentery which
contains its blood supply - a clinically relevant detail during appendectomy |
| omental appendage |
fat-filled pendants of peritoneum projecting from the visceral peritoneum
on the surface of the large intestine |
there are many omental appendages on the large intestine (except the rectum)
and none on the small intestine; also known as: appendix epiploica |
| omental apron |
part of the greater omentum that hangs inferiorly from the transverse colon |
omental apron is derived from the dorsal mesogastrium during development |
| omental bursa |
part of the peritoneal cavity located posterior to the stomach and lesser
omentum |
omental bursa is continuous with the greater peritoneal sac at the omental
(epiploic) foramen; also known as: lesser peritoneal sac |
| omental foramen |
passageway between the greater peritoneal sac and the lesser peritoneal
sac |
located posterior to the hepatoduodenal ligament; also known as: epiploic
foramen |
| pancreas |
exocrine and endocrine gland located posterior to the stomach on the posterior
abdominal wall |
retroperitoneal; pancreas functions as a digestive and an endocrine (insulin
production) gland; main pancreatic duct drains the exocrine secretions of the
tail, body and lower part of the head to the greater duodenal papilla within
the 2nd part of the duodenum; accessory pancreatic duct drains the exocrine
secretions of the upper body and part of the head to the lesser duodenal papilla |
| pancreas, body of |
part of the pancreas between the head and tail |
body of pancreas stretches to the left from the neck of the pancreas; splenic
a. lies on the superior border of the body; splenic v. lies posterior to the
body |
| pancreas, head of |
part of the pancreas located to the right, within the curvature of the duodenum |
the pancreatic arterial arcades are formed on the anterior and posterior
surfaces of the head of the pancreas |
| pancreas, neck of |
the junction between the head and the body of the pancreas |
the neck of the pancreas is a constricted region to the left of the head;
superior mesenteric a. arises from the abdominal aorta posterior to the neck
of the pancreas |
| pancreas, tail of |
part of the pancreas that forms the tapered left end of the organ |
tail of the pancreas extends into the splenorenal (lienorenal) ligament
toward the hilum of the spleen |
| pancreas, uncinate process of |
lowest part of the head of the pancreas |
the uncinate process lies posterior to the superior mesenteric vessels |
| pancreatic duct, accessory |
drains part of the head of the pancreas |
accessory pancreatic ducts opens onto the lesser duodenal papilla |
| pancreatic duct, main |
drains the tail, body and part of the head of the pancreas |
main pancreatic duct unites with the common bile duct at the hepatopancreatic
ampulla; it drains onto the greater duodenal papilla |
| pararenal fat |
extraperitoneal fat surrounding the kidney |
pararenal fat is located external to the renal fascia |
| perirenal fat |
extraperitoneal fat surrounding the kidney |
perirenal fat is located within the renal fascia; it is also located within
the renal sinus surrounding the calyces and blood vessels |
| peritoneum |
serous membrane lining the peritoneal cavity |
visceral peritoneum lies on the surfaces of the abdominal and pelvic organs;
parietal peritoneum lines the inner surfaces of the walls of the abdominopelvic
cavity |
| peritoneum, parietal |
serous membrane lining the inner surfaces of the walls of the abdominopelvic
cavity |
peritoneum, pleura and pericardium are all serous membranes that formed
from the same layer of tissue (splanchnic mesoderm) in the embryo |
| peritoneum, visceral |
serous membrane lying on the surfaces of the abdominal and pelvic organs |
visceral peritoneum is formed from the splanchnic mesoderm in the embryo |
| porta hepatis |
region of the visceral surface of the liver where hepatic ducts, hepatic
aa. & portal v. enter/leave |
porta hepatis is equivalent to the hilum of the spleen or lung |
| pylorus of the stomach |
constricted distal part of the stomach to the right of the angular notch |
pyloris contains the pyloric antrum and the pyloric sphincter (Greek, pylorus = a gatekeeper) |
| quadrate lobe |
part of liver between the bed of the gallbladder and the round ligament
of the liver |
quadrate lobe has the external appearance of being part of the right lobe, but it is functionally part of the left lobe (Latin, quadrate = square) |
| renal columns |
columns of tissue that are histologically identical to tissue found in the
renal cortex, but which are located in the medulla between the renal pyramids |
interlobar arteries pass from the renal sinus to the renal cortex within
the renal columns |
| renal cortex |
outer layer of kidney |
renal cortex contains the majority of the glomeruli |
| renal fascia |
a fascial pouch derived from extraperitoneal connective tissue that contains
the kidneys, the suprarenal glands, the renal vessels and perirenal fat |
renal fascia of the right and left sides is joined across the midline in
close relationship to the renal aa. and vv.; renal fascia encapsulates the
inferior vena cava and aorta at the level of origin of the renal vessels; do
not confuse renal fascia with the renal capsule - the renal capsule is histologically
part of the kidney and there is no fat between it and the kidney |
| renal hilum |
opening on medial margin of the kidney leading into the renal sinus |
the renal vessels enter/leave the kidney at the hilum; the renal pelvis
leaves the kidney at the hilum |
| renal medulla |
inner layer of the kidney |
renal medulla contains most of the tubules of the kidney organized as renal
pyramids; renal columns consist of cortex-like tissue arranged between the
pyramids in the renal medulla |
| renal papilla |
tip of renal pyramid projecting into a minor calyx |
several minor calyces combine to form a major calyx; all of the major calyces in the kidney unite to form the renal pelvis (Latin, papilla = a pimple or nipple) |
| renal pelvis |
large collecting duct for urine that is formed by the union of the major
calyces |
renal pelvis is the dilated origin of the ureter; it is located at the renal
hilum and is surrounded by the renal sinus |
| renal pyramid |
cone-shaped arrangement of tubules in the renal medulla |
tip of the renal pyramid (papilla) projects into a minor calyx |
| renal sinus |
hollowed out area on the medial margin of the kidney |
renal sinus opens at the renal hilum; it contains the renal aa. and vv.,
major calyces and renal pelvis, perirenal fat |
| right colic flexure |
junction of the ascending colon and the transverse colon |
right colic flexure lies anterior to the lower part of the right kidney
and inferior to the right lobe of the liver; also known as: hepatic flexure |
| round ligament of the liver |
cord-like ligament that lies within the free margin of the falciform ligament |
round ligament of the liver courses from the liver to the umbilicus; it
is the remnant of the umbilical v.; also known as: ligamentum teres hepatis |
| rugae of the stomach |
folds of the mucosal lining of the stomach |
rugae are ridges that generally run from the cardia of the stomach toward the pyloris along the lesser curvature; also known as: gastric folds (Latin, rugae = a wrinkle) |
| sigmoid colon |
part of the distal large intestine located within the lower left quadrant |
sigmoid colon is continuous proximally with the descending colon at the left pelvic brim; it is continuous distally with the rectum at the level of the 3rd sacral vertebra; it is suspended from posterior abdominal wall by the sigmoid mesocolon (Greek, sigmoid = resembles the greek letter sigma) |
| sigmoid mesocolon |
peritoneum connecting the sigmoid colon to posterior abdominal wall |
branches of the inferior mesenteric a. approach the sigmoid colon within the sigmoid mesocolon; ascending preganglionic parasympathetic axons course through the sigmoid mesocolon an their route from the pelvis (S2,3,4) to the descending colon (Greek, sigmoid = resembles the greek letter sigma) |
| spleen |
lymphatic organ suspended within the greater omentum in the upper left quadrant |
spleen is connected to the greater curvature of the stomach by the gastrosplenic
(gastrolienal) ligament; it is connected to the left kidney by the splenorenal
(lienorenal) ligament; spleen is covered by visceral peritoneum on all of its
surfaces |
| splenorenal ligament |
peritoneum that attaches the spleen to the posterior abdominal wall over
the left kidney
| splenorenal ligament develops from the dorsal mesogastrium of the embryo;
also known as: lienorenal ligament |
| stomach |
dilated portion of the digestive system located primarily in the upper left
quadrant |
stomach rotates during embryonic development so that the lesser curvature
(originally the anterior surface) faces superiorly and to the right, the greater
curvature (originally the posterior surface) faces inferiorly and to the left |
| stomach, body of |
part of the stomach between the fundus and the pylorus |
mucosal surface of the body of the stomach near the lesser curvature has
gastric folds |
| stomach, fundus of |
expanded superior part of the stomach above the entrance of the esophagus |
fundus may contain a gas bubble in X rays of patients filmed in a standing
position |
| suprarenal gland |
endocrine gland located superomedial to the kidney; right suprarenal gland
is somewhat triangular in shape, left suprarenal gland is semilunar in shape |
suprarenal cortex manufactures corticosteroids; suprarenal medulla manufactures
epinephrine and norepinephrine; suprarenal medulla receives preganglionic sympathetic
innervation from the greater thoracic splanchnic n.; also known as: adrenal
gland |
| teniae coli |
band of longitudinal smooth muscle on the surface of the large intestine |
there are three teniae coli, named according to their position on the transverse colon: tenia omentalis (located at the line of attachment of the omental apron), tenia mesocolica (located at the line of attachment of the transverse mesocolon), tenia libera ("free" tenia - it has no mesenteric attachment obscuring it) (Latin/Greek, teniae = band or tape) |
| tenia libera |
band of longitudinal smooth muscle on the large intestine |
tenia libera has no attachment to any peritoneal structure; the easiest of the tenia to see (Latin/Greek, teniae = band or tape + libera = free) |
| tenia mesocolica |
band of longitudinal smooth muscle on the large intestine |
tenia mesocolica is located at the line of attachment of the transverse mesocolon on the transverse colon (Latin/Greek, teniae = band or tape) |
| tenia omentalis |
band of longitudinal smooth muscle on the large intestine |
tenia omentalis is located at the line of attachment of the omental apron on the transverse colon (Latin/Greek, teniae = band or tape) |
| transverse colon |
part of the large intestine located between the left and right colic flexures |
transverse colon is continuous proximally with the ascending colon at the
right colic (hepatic) flexure; it is continuous distally with the descending
colon at the left colic (splenic) flexure; it is suspended from the posterior
abdominal wall by the transverse mesocolon |
| transverse mesocolon |
peritoneum connecting the transverse colon to the posterior abdominal wall |
transverse mesocolon represents the fusion of the transverse mesocolon with
one layer of the greater omentum in the embryo; it forms the floor of the lesser
peritoneal sac |
| triangular ligament |
extreme left or right end of the coronary ligament of the liver |
triangular ligaments are formed by the joining of the anterior and posterior
laminae of the coronary ligament; they delineate the right and left extremes
of the bare area of the liver |
| ureter |
muscular tube that serves as the duct of the kidney to carry urine to the
bladder |
ureter is continuous proximally with the renal pelvis; it passes over the pelvic brim medial to the testicular/ovarian vessels; it passes obliquely through the posterior wall of the urinary bladder and drains at the posterolateral angle of the vesical trigone (Greek, oueter/utreter = urinary canal) |
Visceral Structures of the Pelvis and Perineum -
Arranged Alphabetically
|
| Organ/Part of Organ |
Location/Description |
Notes |
| ampulla of the ductus deferens |
dilated part of the ductus deferens located posterior to the bladder |
ampulla of the ductus deferens joins with the duct of the seminal vesical to form the ejaculatory duct (Latin, ampulla = a flask or dilated part of a duct or channel + ductus = to lead + deferens = to carry away) |
| ampulla of the uterine tube |
widest and longest part of the uterine tube |
ampulla of the uterine tube arches over the ovary and ends laterally in the infundibulum (Latin, ampulla = a flask or dilated part of a duct or channel) |
| anal canal |
terminal end of the digestive tract |
anal canal is continuous with the rectum above and opens at the anus below;
it is regulated by external and internal anal sphincters |
| anal columns |
longitudinal folds of mucosa on the inner wall of the anal canal |
anal columns are connected inferiorly by anal valves; rectal vessels lie
beneath the submucosa of the anal columns |
| anal valves |
folds of mucosa joining adjacent anal columns at their inferior ends |
anal valves can be difficult to locate in the older individual |
| appendix of the epididymis |
small appendage on the head of the epididymis |
appendix of the epididymis is a remnant of the most cranial part of the
mesonephric duct |
| appendix of the testis |
small appendage on the upper testis |
appendix of the testis is a remnant of the paramesonephric duct |
| bladder, urinary |
hollow muscular organ posterior to the pubic symphysis and body of the pubis
that acts as a reservoir for urine |
urinary bladder is held in place by the pubovesical/puboprostatic ligaments;
ureters enter the posterolateral surface of the bladder at the posterior two
angles of the vesical trigone |
| body of the uterus |
part of the uterus between the fundus and the isthmus |
the uterine cavity is thin anteroposteriorly and wide in the transverse
plane |
| broad ligament |
peritoneal fold extending from the pelvic walls to the uterus and uterine
tubes |
broad ligament has three named parts: mesovarium, mesosalpinx, mesometrium |
| bulb of the penis |
expanded part of the corpus spongiosum that attaches to the perineal membrane |
bulb of the penis is covered on its superficial surface by the bulbospongiosus
muscle; it contains a portion of the spongy/penile urethra; it is the homologue
of the bulb of the vestibule |
| bulb of the vestibule |
erectile tissue located on either side of the vestibule of the vagina, attached
to the perineal membrane |
bulb of the vestibule is continuous with the glans clitoris; it is covered
on its superficial surface by the bulbospongiosus muscle; it is the homologue
of the bulb of the penis |
| bulbourethral gland |
an exocrine gland located posterolateral to the membranous urethra within
the sphincter urethrae muscle (in the urogenital diaphragm) |
male only; its duct passes through the perineal membrane and drains into
the spongy/penile urethra in the bulb of penis |
| cardinal ligament |
condensations of endopelvic (extraperitoneal) connective tissue surrounding
the uterine vessels within the base of the broad ligament |
cardinal ligament helps in support of the uterus by attaching the uterine
isthmus to the lateral pelvic wall |
| cervix |
narrowed inferior end of the uterus |
cervix is inferior to the isthmus of the uterus and projects into the vagina; it is surrounded by the vaginal fornices (anterior, posterior and lateral) (Latin, cervix = neck) |
| clitoris |
combination of 3 erectile bodies: glans clitoris and 2 corpora cavernosa
clitoris |
clitoris is covered by smooth skin |
| corpus cavernosum |
primary erectile bodies (paired) of the penis and clitoris |
corpora cavernosa attach via the crura to the ischiopubic rami and the perineal membrane; each crus is covered by an ischiocavernosus muscle; supplied by the deep a. of the penis/clitoris (Latin, corpus = body) |
| corpus spongiosum |
midline erectile body, attached to the perineal membrane at its proximal
end (bulb of the penis) |
corpus spongiosum expands distally as the glans penis which caps the distal ends of the corpora cavernosa; it contains the spongy/penile urethra (Latin, corpus = body) |
| crus clitoris |
lateral part of the corpus cavernosum which is attached to the ischiopubic
ramus and the perineal membrane |
crus clitoris is covered on its superficial surface by the ischiocavernosus
muscle |
| crus of penis |
lateral part of the corpus cavernosum which is attached to the ischiopubic
ramus and the perineal membrane |
crus penis is covered on its superficial surface by the ischiocavernosus
muscle |
| ductus deferens |
duct of the testis |
ductus deferens is continuous with the tail of the epididymis; it passes through the superficial inguinal ring, inguinal canal and deep inguinal ring to reach the posteroinferior surface of the bladder where it joins with the duct of the seminal vesicle to form the ejaculatory duct (Latin, ductus = to lead + deferens = to carry away) |
| ejaculatory duct |
duct formed by the union of the duct of the seminal vesicle and the ampulla
of the ductus deferens |
ejaculatory duct passes through the prostate gland to empty onto the seminal
colliculus along the urethral crest in the prostatic urethra |
| epididymis |
beginning of the duct system of the testis |
the head of the epididymis is located on the superior surface of the testis and receives sperm from the efferent ductules; the body of the epididymis lies posterolateral to the testis and is separated from the testis by the sinus of the epididymis; the tail of the epididymis is located inferiorly and is continuous with the ductus deferens; the ductus deferens ascends to pass through the abdominal wall via the inguinal canal (Greek, epididymis = covering of the testicle) |
| fascia, deep penile/clitoral |
an extension of the muscular fascia of the ischiocavernosus m. and bulbospongiosus
m. onto the shaft of penis/clitoris |
deep fascia of the penis/clitoris forms a tubular sheath surrounding the
erectile bodies, dorsal n. of the penis/clitoris, dorsal a. of the penis/clitoris,
deep dorsal v. of the penis/clitoris; the superficial dorsal v. of penis/clitoris
lies superficial to the deep fascia of the penis/clitoris; deep fascia of the
penis is also known as: Buck's fascia |
| fascia, external spermatic |
outermost covering of the spermatic cord that is derived from a layer of
the abdominal wall |
derived from the aponeurosis of the external abdominal oblique muscle |
| fascia, cremasteric |
intermediate covering layer of the spermatic cord |
derived from the internal abdominal oblique muscle |
| fascia, internal spermatic |
innermost covering of the spermatic cord |
derived from the transversalis fascia |
| fossa navicularis |
dilation of the spongy/penile urethra in the glans penis |
the largest diameter of the penile urethra occurs here (Latin, navicular = a small boat-shaped structure) |
| fimbria of the uterine tube |
finger-like projections surrounding the opening into the uterine tube |
fimbria spread over the medial surface of the ovary; the ovarian fimbria is an extra long fimbria that attaches to the ovary (Latin, fimbria = fringe) |
| fundiform ligament |
specialization of the membranous layer of superficial (Scarpa's) fascia
passing from the lower abdominal wall onto the base of the penis/clitoris |
suspensory ligament of the penis/clitoris is a deep fascia specialization
that lies deep to the fundiform ligament |
| fundus of the uterus |
the rounded anterosuperior part of the uterus |
fundus of the uterus is defined as that portion of the uterus located superior
to an imaginary line joining the points of entry of the uterine tubes; the
uterus is normally anteverted and anteflexed, so the fundus normally points
anterosuperiorly |
| glans penis/clitoridis |
expanded distal end of the corpus spongiosum which caps the ends of the
corpora cavernosa |
the fossa navicularis is an expanded portion of the penile urethra that occurs in the glans (Latin, glans = acorn) |
| greater vestibular gland |
an exocrine gland located in the superficial perineal space posterior to
the bulb of the vestibule |
greater vestibular gland is covered by the bulbospongiosus muscle; it produces
a mucous secretion that drains into the vestibule of the vagina for lubrication
of the vulva |
| hymen |
thin, usually incomplete septum at the inferior vaginal orifice |
the hymen is the remnant of the urogenital septum of the embryo, and the hymeneal caruncles are remnants of the hymen (Greek, hymen = membrane) |
| infundibulum of the uterine tube |
funnel-shaped distal end of the uterine tube |
fimbria are attached to the margin of the infundibulum (Latin, infundibulum = a funnel) |
| interureteric ridge |
mucosal fold on the inner posterior wall of the bladder connecting the paired
ureteric orifices |
interureteric ridge is the superior boundary of the vesical trigone |
| isthmus of the uterine tube |
constricted part of the uterine tube that is adjacent to the uterus |
isthmus of the uterine tube is the narrowest part |
| isthmus of the uterus |
constricted part of the uterus between the body and the cervix |
isthmus of the uterus is about 1 cm in length and its cavity enters into
the internal cervical os |
| labia majora |
fat-filled elevations of hair-covered skin lying on either side of the vestibule
of the vagina |
labia majora are joined across the midline by the anterior and posterior labial commissures; they blend into each other anteriorly to form the mons pubis (Latin, labia = lips) |
| labia minora |
paired folds of hairless skin located medial to the labia majora and extending
posteroinferiorly from the clitoris |
the anterior end of each labium minus divides: the anterior division of each labium forms the prepuce of the clitoris and the posterior division of each labium forms the frenulum of the clitoris (Latin, labia = lips) |
| ligamentum teres uteri |
a connective tissue band that attaches to the inner aspect of the labium
majus and the uterus |
ligamentum teres uteri traverses the superficial inguinal ring, inguinal canal and deep inguinal ring to reach the lateral surface of the uterus below the uterine tube; it is a remnant of the gubernaculum; it is continuous with the ovarian ligament; it holds the fundus of the uterus forward; also known as: round ligament of the uterus (Latin, teres = round) |
| mesometrium |
part of the broad ligament below the junction of the mesosalpinx and the
mesovarium |
mesovarium attaches the body of the uterus to the pelvic wall |
| mesosalpinx |
part of broad ligament that supports the uterine tube |
mesosalpinx extends inferiorly to meet the root of the mesovarium; it attaches the uterine tube to the mesometrium (Greek, salpinx = a trumpet) |
| mesovarium |
part of broad ligament that forms a shelf-like fold supporting the ovary |
mesovarium is located perpendicular to the plane of the mesosalpinx and
mesometrium; it attaches the ovary to the mesometrium and mesosalpinx |
| ovarian ligament |
a band of connective tissue that connects the ovary to the lateral surface
of the uterus |
a remnant of the gubernaculum; it is continuous with the round ligament
of the uterus at the lateral surface of the uterus; ovarian ligament lies within
the mesovarium; also known as: proper ovarian ligament |
| ovary |
female gonad that lies in the ovarian fossa within the true pelvis in contact
with the fimbria of the uterine tube |
ovary is both an endocrine and an exocrine gland; it is held in place by
the ovarian ligament, mesovarium, and suspensory ligament of the ovary |
| pectinate line |
an irregular line joining the undersides of the anal valves |
pectinate line is where the mucosal lining of the digestive tract becomes
continuous with the skin of the anal aperture |
| perineal membrane |
membrane stretching across the urogenital triangle attaching to both ischiopubic
rami |
perineal membrane is pierced by the urethra, vagina and branches of the
pudendal neurovascular bundle |
| posterior fornix of the vagina |
space within the vaginal canal posterior to the cervix |
an incision made superiorly through posterior fornix will enter the rectouterine pouch of the peritoneal cavity (Latin, fornix = an arch or vault) |
| prepuce |
fold of smooth skin extending over the glans penis/clitoris |
the anterior divisions of the labia minora combine to form the prepuce of the clitoris (Latin, praeputium = foreskin) |
| prostate |
exocrine gland located inferior to the urinary bladder and superior to the
urogenital diaphragm |
multiple small ducts drain into the prostatic urethra as it passes through
the prostate; subject to benign and malignant enlargement, which may compromise
micturition due to projection of the uvula into the bladder |
| prostatic utricle |
a small blind diverticulum in the posterior wall of the prostatic urethra
on the summit of the seminal colliculus |
prostatic utricle is a remnant of the fused lower ends of the paramesonephric ducts - the fused paramesonephric ducts form the uterine canal in the female (Latin, utricle = a skin bag) |
| rectouterine fold |
a peritoneal fold extending across the floor of the pelvic cavity from the
sacrum (beside the rectum) to the uterus |
rectouterine fold contains the rectouterine ligament which is a condensation
of endopelvic fascia that is important for support of the uterus |
| rectouterine ligament |
a condensation of extraperitoneal connective tissue & smooth muscle (rectouterine
muscle) connecting the isthmus of the uterus to the sacrum |
rectouterine ligament is important for support of the uterus |
| rectum |
distal end of the colon |
rectum begins at about the S3 vertebral level; it is continuous distally
with the anal canal |
| round ligament of the uterus |
a connective tissue band that attaches to the inner aspect of the labium
majus and the uterus |
round ligament of the uterus traverses the superficial inguinal ring, inguinal
canal and deep inguinal ring to reach the lateral surface of the uterus below
the uterine tube; it is a remnant of the gubernaculum; it is continuous with
the ovarian ligament; it holds the fundus of the uterus forward; also known
as: ligamentum teres uteri |
| scrotal ligament |
band of connective tissue that attaches the inferior end of the testis to
the inner aspect of the scrotal sac |
scrotal ligament is the remnant of the gubernaculum testis |
| scrotum |
sac of hair-covered skin containing the testis |
in the scrotum the fatty and membranous layers of the superficial fascia
(as seen in the lower abdominal wall) are fused to form the tunica dartos scroti |
| seminal colliculus |
elevation on the posterior wall of the prostatic urethra |
the seminal colliculus is a mound in the posterior wall of the prostatic urethra; on its summit is found the opening of the prostatic utricle (Latin, colliculus = mound) |
| seminal vesicle |
blind sac located on the posterior surface of the bladder lateral to the
ampulla of the ductus deferens |
seminal vesicle produces seminal fluid; its duct joins with the ampulla
of the ductus deferens to form the ejaculatory duct |
| sinus of the epididymis |
a thin space within the tunica vaginalis testis between the body of the
epididymis and the testis |
sinus of the epididymis is lined by a serous membrane (visceral layer of
the tunica vaginalis testis) |
| spermatic cord |
bundle of vessels, nerves and lymphatics ensheathed in tissue layers derived
from the abdominal wall; it begins at the deep inguinal ring, passes through
the inguinal canal and the superficial ring to reach the testis in the scrotum |
spermatic cord contains the: ductus deferens, testicular a., pampiniform
plexus, deferential a. & v. and genital br. of the genitofemoral n.; coverings
of the cord are the: internal spermatic fascia (from the transversalis fascia),
cremasteric muscle and fascia (from the internal abdominal oblique), external
spermatic fascia (from the external abdominal oblique aponeurosis) |
| suspensory ligament of the penis/clitoris |
a specialization of deep fascia connecting the proximal end of the penis/clitoris
to the pubis and pubic symphysis |
the fundiform ligament is a specialization of superficial fascia that lies
superficial to the suspensory ligament |
| testis |
an endocrine and exocrine gland contained within the scrotum |
testis is the male gonad; its exocrine product is sperm which drain to the
head of the epididymis via efferent ductules; its endocrine product is testosterone;
the testis migrates into the scrotum shortly before birth; it is tethered to
the scrotum inferiorly by the scrotal ligament (a remnant of the gubernaculum) |
| tunica albuginea, corpus cavernosum |
outer white fibrous covering of the corpus cavernosum of the penis/clitoris |
tunica albuginea is a dense connective tissue layer that is not distensible, causing erection when the corpus cavernosum becomes engorged with blood (Latin, tunica albuginea = white coat) |
| tunica albuginea, testis |
outer white fibrous covering of the testis |
tunica albuginea is a dense connective tissue capsule that is covered on its external surface by the visceral layer of the tunica vaginalis testis (Latin, tunica albuginea = white coat) |
| tunica dartos scroti |
a subcutaneous layer of smooth muscle located in the scrotum |
fatty and membranous layers of the superficial fascia (as seen in the lower abdominal wall) are fused in the scrotum to form the tunica dartos scroti (Latin, tunica = a coat + dartos = leather) |
| tunica vaginalis testis |
a peritoneal sac located anterolateral to the testis |
tunica vaginalis testis has two layers: visceral and parietal; the visceral layer lies on the anterolateral surface of the testis and epididymis; the parietal layer lines the inner surface of the scrotal sac; (Latin, tunica = a coat + vaginalis = sheath) |
| urethra |
duct that drains the urinary bladder |
urethra has three parts in the male: prostatic, membranous & penile/spongy;
female urethra is much shorter than the male urethra, consisting of the membranous
part only |
| urethra, membranous |
part of the urethra that passes through the urogenital diaphragm (sphincter
urethrae muscle and perineal membrane) |
female: membranous urethra connects the urinary bladder to the external
urethral orifice at the vestibule of the vagina; male: membranous urethra connects
the prostatic urethra with the spongy/penile urethra |
| urethra, penile |
part of the urethra contained within the bulb and the corpus spongiosum
of the penis |
longest part of male urethra; penile urethra has a dilation in the region
of the glans called the navicular fossa; also known as: spongy urethra |
| urethra, prostatic |
part of the male urethra passing through the prostate gland |
prostatic urethra begins at the internal urethral orifice at the anteroinferior
angle of the vesical trigone; posterior wall of the urethra has an elevated
ridge called the urethral crest with a prominence called the seminal colliculus
(veru montanum); seminal colliculus has a blind diverticulum called the prostatic
utricle with orifices of ejaculatory ducts located below it |
| urethra, spongy |
part of the urethra contained within the bulb and the corpus spongiosum
of the penis |
longest part of male urethra; spongy urethra has a dilation in the region
of the glans called the navicular fossa; also known as: penile urethra |
| ureter |
muscular tube that serves as the duct of the kidney to carry urine to the
bladder |
ureter is continuous proximally with the renal pelvis; it passes over the pelvic brim medial to the testicular/ovarian vessels; it passes obliquely through the posterior wall of the urinary bladder and drains at the posterolateral angle of the vesical trigone (Greek, oureter/ureter = urinary canal) |
| uterine tube |
the duct of the ovary; it extends from the ovary to the uterus |
uterine tube has four named parts: infundibulum is the funnel shaped opening
- fimbria encircle this opening; ampulla is a dilated region that connects
the infundibulum with the isthmus; isthmus is the constricted part nearest
the uterus; intramural part is within the uterine wall |
| uterus |
hollow muscular organ within which the fertilized ovum develops; normally
lies anteverted posterosuperior to the bladder |
uterus is anteflexed (curved anteroinferiorly) at the uterine isthmus; the
fundus is the part superior to the entrance of the uterine tubes and it normally
lies anterosuperiorly; the body meets the cervix at a constricted area called
the isthmus; the cervix projects into the vagina |
| uvula of the bladder |
elevation of the inner bladder wall posterosuperior to the internal urethral
orifice |
uvula is caused by the middle lobe of the prostate gland; if the prostate becomes enlarged (either benin hypertrophy or malignancy) the uvula can constrict the internal urethral orifice and cause difficulty in voiding the bladder; only found in males (Latin, uvula = grape) |
| vagina |
part of the female genital canal located between the vestibule and the cervix |
vaginal fornices surround the cervix; the word "vagina" is derived
from the Latin word for sheath |
| vestibule of the vagina |
region inferior to the hymen/hymeneal caruncles and between the labia minora |
vestibule of the vagina contains the external urethral orifice, the opening
of the vagina and the openings of the greater vestibular glands |
| vesical trigone |
smooth triangular region located on the inner surface of the posterior wall
of the urinary bladder |
vesical trigone is bounded by the openings of the ureters (2) superolaterally,
the interureteric ridge between the openings of the ureters and the internal
urethral orifice inferiorly |
Visceral Structures of the Head and Neck - Arranged Alphabetically
|
| Organ |
Location/Description |
Notes |
| anterior median fissure |
midline fissure on the anterior surface of the spinal cord and medulla |
anterior spinal artery courses on the superficial surface of the spinal
cord in this fissure |
| apex of cuneus |
portion of the cuneus seen in an inferior view of the cerebral hemisphere |
contains part of the visual cortex (Latin, cuneus = wedge) |
| arachnoid granulations |
projections of arachnoid mater which pass through the meningeal layer of
the dura into the dural venous sinuses; they are most prominent in the superior
sagittal sinus |
CSF returns to the venous circulation by passing from arachnoid granulations into the blood contained within the dural venous sinuses (Greek, arachnoid = resembles a spider-web) |
| arachnoid mater |
intermediate one of the three layers of meninges |
arachnoid mater is a thin membrane which is pressed against the inner surface
of the dura mater by cerebrospinal fluid pressure; arachnids are spiders, the
space deep to this layer (subarachnoid space) has a spider web-like appearance |
| aryepiglottic fold |
a fold of mucous membrane within the laryngopharynx that extends from the
arytenoid cartilage to the epiglottis |
aryepiglottic fold covers the aryepiglottic muscle |
| arytenoid cartilage |
a pyramid-shaped cartilage located on the superior margin of the cricoid
lamina of the larynx |
arytenoid cartilage is connected: above to the epiglottis via aryepiglottic m. and anteriorly to the thyroid cartilage via the vocal ligament; the paired arytenoid cartilages are pulled together (adducted) by the arytenoid mm. (transverse and oblique) (Greek, arytenoid = ladle-shaped) |
| body of fornix |
a group of nerve cell fibers arching beneath the corpus callosum |
main efferent fiber system of the hippocampal formation (Latin, fornix = arch or vault) |
| brain stem |
comprised of: midbrain, pons & medulla oblongata |
contains the nuclei of cranial nerves III-XII |
| choroid plexus |
vascular membranes that occur within the ventricles |
choroid plexus produces cerebrospinal fluid |
| corniculate cartilage |
a small cartilage located on the apex of the arytenoid cartilage of the
larynx |
corniculate cartilage is located at the posterior end of the aryepiglottic fold |
| central canal of spinal cord |
small opening in the center of the spinal cord |
continuous with the central canal of the medulla and, through it, with the
fourth ventricle of the brain |
| cerebral hemispheres |
comprised of: cortex featuring gyri, sulci, fissures & lobes; commissures
connecting parts; basal ganglia; contains lateral ventricles; termination of
the olfactory tract (cranial nerve I) |
also known as: telencephalon |
| cerebral aqueduct |
canal connecting the third and fourth ventricles, passing through the midbrain |
also known as: aqueduct of Sylvius |
| cerebral peduncle |
a large fiber bundle that connects the forebrain with the hindbrain |
contains axons that control voluntary movement (corticospinal and corticopontine
tracts); also known as: crus cerebri |
| cerebellum |
posterior part of the metencephalon |
largest part of hindbrain; important for coordination of movement |
| cerebellar peduncle, middle |
largest (and intermediate) of the three cerebellar peduncles |
connects the cerebellum to the pons |
| CN II (optic) |
the portion of the visual pathway between the retina and the optic chiasm;
it passes through the optic canal to enter the cranial cavity |
vision |
| CN III (oculomotor) |
emerges from the ventral surface of the brainstem near the midline at the
caudal end of the midbrain; courses through the lateral wall of the cavernous
sinus and exits the middle cranial fossa by passing through the superior orbital
fissure |
motor supply to skeletal mm.: levator palpebrae superioris, superior rectus,
medial rectus, inferior rectus, inferior oblique; preganglionic parasympathetic
to ciliary ganglion, postganglionic parasympathetic via short ciliary nn.to:
ciliary m. & sphincter pupillae m. |
| CN IV (trochlear) |
emerges from the dorsal surface of the midbrain near the midline, just caudal
to the inferior colliculus; courses through the lateral wall of the cavernous
sinus and exits the middle cranial fossa by passing through the superior orbital
fissure |
motor supply for the superior oblique muscle of the eye; only cranial nerve to cross the midline of the brainstem - this crossover happens inside of the brainstem (Latin, tochlea = a pulley) |
| CN V (trigeminal) |
large sensory nerve arising from the ventral surface of the pons, also contains
a motor component; courses to the middle cranial fossa where it separates into
three divisions at the trigeminal ganglion: ophthalmic division passes out
of cranial cavity by passing through superior orbital fissure, maxillary division
passes through foramen rotundum, mandibular division passes through foramen
ovale; ophthalmic and maxillary divisions course through the lateral wall of
the cavernous sinus |
motor to the muscles of branchial arch origin: temporalis, masseter, lateral
& medial pterygoid, anterior belly of digastric, mylohyoid, tensor veli palatini,
tensor tympani; three divisions supply sensory innervation the to skin of the
face, mucosa of the nasal & oral cavities, mucosa of the anterior 2/3rds of
tongue (general sense only) |
| CN VI (abducens) |
small cranial nerve arising from the caudal end of the pons; emerges from
the junction of the pons and medulla; courses anteriorly through the cavernous
sinus lateral to the internal carotid artery, then exits the middle cranial
fossa by passing through the superior orbital fissure |
motor innervation of the lateral rectus muscle of the eye (Latin, abducens = to draw away) |
| CN VII (facial) |
cranial nerve arising from the caudal end of the pons; emerges from the
junction of the pons and medulla just lateral to the abducens nerve; courses
laterally to exit the posterior cranial fossa by entering the internal acoustic
meatus |
motor to muscles of facial expression; special sensory (taste) to anterior
2/3 of the tongue; secretomotor (parasympathetic) to: lacrimal, submandibular,
sublingual, and mucous glands of nasal & oral cavities |
| CN VIII (vestibulocochlear) |
cranial nerve arising from the caudal end of the pons; emerges from the
junction of the pons and medulla just lateral to the facial nerve; courses
laterally to exit the posterior cranial fossa by entering the internal acoustic
meatus; divides within the temporal bone into vestibular and cochlear parts |
vestibular portion: balance/proprioception; cochlear portion: hearing |
| CN IX (glossopharyngeal) |
cranial nerve emerging from the rostral end of the ventral surface of the
medulla lateral to the olive; it emerges rostral to the vagus nerve and caudal
to the vestibulocochlear nerve; it courses inferiorly to exit the posterior
cranial fossa by passing through the jugular foramen in company with the vagus
and accessory nn. |
motor to the stylopharyngeus m.; secretomotor to the parotid gland (preganglionic
parasympathetic via lesser petrosal n. to otic ganglion, postganglionic parasympathetic
via auriculotemporal n.); taste to posterior 1/3 of the tongue; sensory to
middle ear and auditory tube |
| CN X (vagus) |
cranial nerve emerging from the ventral surface of the medulla lateral to
the olive and just caudal to the glossopharyngeal nerve; it courses inferiorly
to exit the posterior cranial fossa by passing through the jugular foramen
in company with the glossopharyngeal and accessory nn. |
the primary parasympathetic nerve to the organs of the neck, thorax and abdomen; motor supply to intrinsic muscles of the larynx, pharynx (except stylopharyngeus), and palate (except tensor veli palatini); brings back visceral sensations from the thoracic and abdominal organs (Latin, vagus = wanderer, due to its wide distribution to body cavities) |
| CN XI (accessory) |
cranial nerve emerging from the ventral surface of the medulla lateral and
inferior to the olive and just caudal to the vagus nerve and from the ventral
surface of the cervical spinal cord; its cranial root joins the vagus nerve;
its spinal root arises from upper levels of the cervical spinal cord and courses
superiorly to enter the posterior cranial cavity by passing through the foramen
magnum; the spinal portion courses inferiorly to exit the posterior cranial
fossa by passing through the jugular foramen in company with the glossopharyngeal
and vagus nn. |
motor innervation to the sternocleidomastoid and trapezius mm. |
| CN XII (hypoglossal) |
cranial nerve arising from the ventral surface of the medulla in the sulcus
between the pyramid and the olive; it courses anteriorly to exit the posterior
cranial fossa by passing through the hypoglossal canal |
motor innervation of the intrinsic and extrinsic muscles of the tongue |
| corpus callosum |
midline part of the great cerebral commissure |
connects the paired cerebral hemispheres (Latin, corpus = body) |
| commissure, anterior |
a bundle of association fibers located anterior to the third ventricle |
connects the left and right temporal lobes |
| commissure, posterior |
a bundle of association fibers located posterior to the third ventricle,
just inferior to the pineal gland |
connects various areas of the right and left sides of the midbrain (Latin, commissure = seam) |
| cranial dura mater |
outermost covering of the brain, described as 2 layers: periosteal outer
layer and meningeal inner layer |
dural venous sinuses lie between layers of the cranial dura; meningeal layer
forms three infoldings that help to support the brain: falx cerebri, falx cerebelli,
tentorium cerebelli |
| cricoid cartilage |
inferior and posterior cartilage of the larynx; arch is narrow anteriorly,
lamina is broad posteriorly |
cricoid cartilage is connected: above to the thyroid cartilage via the inferior horn of the thyroid cartilage; above to the conus elasticus; above to the arytenoid cartilages (on lamina); below to the 1st tracheal ring via the cricotracheal ligament (Greek, cricoid = a ring form) |
| cuneus |
part of the cerebral cortex that forms the upper wall of the calcarine fissure |
cortical projection of the lower half of the contralateral visual field (Latin, cuneus = wedge) |
| cuneiform cartilage |
small fibrocartilage nodule located in the posterior end of the aryepiglottic
fold |
cuneiform cartilage is anterior to the corniculate cartilage (Latin, cuneiform = wedge-shaped) |
| conus elasticus |
elastic membrane attaching on the upper margin of the arch of the cricoid
cart and ending in the vocal ligament |
thickened upper margin of the conus elasticus is the vocal ligament |
| diaphragma sellae |
dura mater forming the roof of the hypophyseal fossa |
surrounds the stalk of the hypophysis (pituitary gland) |
| diencephalon |
caudal portion of prosencephalon/forebrain |
comprised of: thalamus, metathalamus, subthalamus, epithalmus; contains the third ventricle (Greek, diencephalon = through the brain) |
| denticulate ligament |
a lateral extension of pia mater from the spinal cord |
denticulate ligament attaches to the dura mater to anchor the spinal cord; it forms a scalloped free border; there are 2 (one on each side) (Latin, denticle = a small tooth) |
| dura mater |
outermost of the meningeal layers covering the brain and spinal cord |
"tough mother"; it is the most durable of the meninges and provides support
and protection for the brain and spinal cord; two types are described which
differ in structure: cranial and spinal |
| dura mater, cranial |
outermost of the meningeal layers covering the brain; it has 2 layers: periosteal
(outer layer) and meningeal (inner layer) |
cranial dura mater participates in the formation of the dural venous sinuses;
it forms infoldings between portions of the brain that help to support the
brain: falx cerebri, falx cerebelli, tentorium cerebelli, diaphragma sellae |
| dura mater, meningeal |
inner layer of the cranial dura mater |
dural venous sinuses lie between layers of the cranial dura mater; the meningeal
layer forms folds that help to support the brain: falx cerebri, falx cerebelli,
tentorium cerebelli |
| dura mater, periosteal |
outer layer of the cranial dura mater |
the periosteal layer of cranial dura mater attaches loosely to the inner
surface of the cranial cavity; equivalent to periosteum of the cranial bones;
participates in the formation of the dural venous sinuses |
| epidural space |
the space external to the sac of spinal dura mater within the vertebral
canal |
the epidural space contains epidural fat and the internal vertebral plexus
of veins which is valveless (clinically relevant) |
| epiglottis |
a single midline cartilage forming the superior part of the larynx |
epiglottis contains the epiglottic cartilage; it moves posteriorly during swallowing to direct food and liquids around the opening into the larynx (Greek, epiglottis = the mouth of the windpipe) |
| esophagus |
the portion of the gastrointestinal tract between the pharynx and the stomach |
connects: superiorly with laryngopharynx at lower border of cricoid cartilage;
inferiorly it passes through diaphragm at the T10 vertebral level to reach
the stomach; the upper 1/3 is skeletal muscle innervated by the recurrent laryngeal,
the lower 2/3rds is smooth muscle innervated by the vagus nn. via the esophageal
plexus |
| falx cerebri |
crescent-shaped fold of dura mater located in the sagittal plane |
falx cerebri lies between the cerebral hemispheres (Latin, falx = sickle) |
| falx cerebelli |
small, crescent-shaped fold of dura mater located in the sagittal plane
|
falx cerebelli lies between the cerebellar hemispheres, but does not pass deeply between them (Latin, falx = sickle) |
| filiform papillae |
small taste buds covering the dorsum of the tongue |
slender, conical papillae found on the anterior 2/3 of the tongue |
| filum terminale internum |
thread-like extension of the pia mater from the conus medullaris of the
spinal cord |
filum terminale internum is best seen between vertebral levels L2 and S2;
it becomes enclosed within the filum terminale externum |
| filum terminale externum |
thread-like extension of the dura mater below the end of the dural sac at
S2 |
it attaches to the coccyx; also known as the coccygeal ligament |
| foramen cecum (of the tongue) |
depression located on the midline of tongue in the "V" of the
sulcus terminalis |
foramen cecum is a remnant of the thyroid diverticulum (Latin, cecum = blind) |
| forebrain |
telencephalon (cerebral hemispheres) plus diencephalon |
site of termination of cranial nerves I and II; contains lateral and third
ventricles; also known as: prosencephalon |
| frenulum of the tongue |
fold of mucous membrane in the midline under the tongue |
sublingual caruncles (drainage of the submandibular gland) can be seen on either side of the frenulum (Latin, frenulum = a bridle) |
| fungiform papillae |
medium-sized papillae located on the sides and tip of the tongue |
fungiform papillae are mushroom-shaped and have a rich blood supply that
gives them a red color |
| glottis |
the vocal folds plus the rima glottidis |
rima glottidis is the opening between the vocal folds |
| gyrus, precentral |
most caudal gyrus of the frontal lobe; it lies rostral to the central sulcus |
contains the primary motor cortex (Latin, gyrus = a circle) |
| gyrus, postcentral |
most rostral gyrus of the parietal lobe; it lies caudal to the central sulcus |
contains the primary sensory cortex (Latin, gyrus = a circle) |
| gyrus, superior temporal |
gyrus between the lateral sulcus and the superior temporal sulcus |
contains the primary auditory cortex (Latin, gyrus = a circle) |
| gyrus, lingual |
the portion of the occipital lobe that lies inferior to the calcarine sulcus |
cortical projection of the upper half of the contralateral visual field (Latin, gyrus = a circle) |
| gyrus, middle temporal |
gyrus between the superior and inferior temporal sulci |
(Latin, gyrus = a circle) |
| gyrus, inferior temporal |
gyrus between the inferior temporal sulcus and the inferior margin of the
temporal lobe |
(Latin, gyrus = a circle) |
| gyrus, parahippocampal |
gyrus on the inferior surface of the temporal lobe that lies lateral to
the midbrain |
the uncus is a medial projection of the parahippocampal gyrus (Latin, gyrus = a circle) |
| gyrus, straight |
gyrus located on the medial side of the olfactory tract |
also known as: gyrus rectus (Latin, gyrus = a circle) |
| gyrus, cingulate |
the portion of the limbic lobe that lies superior to the corpus callosum |
cingulate gyrus is bounded by the callosal sulcus and the cingulate sulcus (Latin, gyrus = a circle) |
| hindbrain |
comprised of: metencephalon (pons and cerebellum) and myelencephalon (medulla
oblongata) |
site of origin for cranial nerves V-XII (except spinal part of the accessory
nerve); contains the fourth ventricle; also known as: rhombencephalon |
| hypophysis |
midline projection of neural and endocrine tissue attached to the floor
of the diencephalon |
also known as: pituitary gland |
| hypothalamus |
a collection on nuclei forming the anterior portion of the lateral wall
of the third ventricle |
controls visceral activity and elicits phenomena associated with the emotions |
| inferior colliculus |
elevation of the midbrain tectum; paired |
part of the corpora quadrigemina; important for auditory reflexes (Latin, colliculus = a mound) |
| infundibulum |
midline stalk of the pituitary gland attached to the floor of the diencephalon |
involved in regulating hormone release from the anterior pituitary (Latin, infundibulum = a funnel) |
| infraglottic cavity |
the portion of the laryngeal cavity that lies inferior to the vocal folds |
bounded superiorly by the glottis and opens inferiorly into the trachea |
| insula |
portion of the cerebrum located deeply within the lateral sulcus |
also known as: island of Reil (Latin, insula = island) |
| interventricular foramen |
communication between the lateral ventricle and the third ventricle; paired,
one on each side |
also known as: foramen of Monro |
| isthmus |
constricted midline connection between the lateral lobes of the thyroid
gland |
it lies anterior to tracheal rings 2-4 |
| lacrimal gland |
tear gland; located in superolateral orbit beneath the orbital plate of
the frontal bone |
lacrimal gland is innervated by postganglionic parasympathetic fibers from
the pterygopalatine ganglion via the communicating br. from the zygomaticotemporal
br. of the zygomatic n. to the to lacrimal n. |
| lacrimal papilla |
a projection located on the edge of the upper or lower eyelid at the medial
angle of the eye |
a lacrimal punctum is located at the apex of each lacrimal papilla (Latin, papilla = nipple/pimple) |
| lacrimal punctum |
an opening located on the edge of the medial end of the upper or lower eyelid |
a lacrimal punctum is located at the apex of each lacrimal papilla; there
are two puncta, one on each eyelid, that drain tears into the lacrimal canaliculi |
| lacrimal sac |
a sac located within the medial wall of orbit, between the orbit and the
nasal cavity |
lacrimal sac receives the lacrimal canaliculi; it drains tears into the nasolacrimal duct (Latin, lacrima = a tear) |
| laryngeal ventricle |
lateral outpouching of the laryngeal mucosa located between the vestibular
fold (false vocal fold) and the vocal fold (true vocal fold) |
laryngeal ventricle may have a small diverticulum called the saccule |
| laryngeal vestibule |
opening into the larynx; the part of the larynx located below the epiglottis,
between the aryepiglottic folds and above the vestibular (false vocal) folds |
lateral wall of the laryngeal ventricle contains the quadrangular membrane
(submucosa) |
| laryngopharynx |
the portion of the pharynx located posterior to the laryngeal inlet and
the posterior wall of the larynx |
connects: superiorly with oropharynx at the superior border of epiglottis,
anteriorly with the larynx through laryngeal inlet, inferiorly with the esophagus
at the lower border of the cricoid cartilage; laryngopharynx contains the piriform
recesses which are lateral to the aryepiglottic folds |
| larynx |
located anterior to the laryngopharynx at level of C4-6 vertebrae |
composed of: thyroid, cricoid, epiglottic, arytenoid, cuneiform & corniculate
cartilages; contains the vocal ligaments; controls the airway |
| lateral aperture |
foramen draining the fourth ventricle laterally into the cerebellomedullary
cistern |
paired; also known as: foramen of Luschka |
| lateral glossoepiglottic fold |
fold of mucous membrane located between the base of the tongue and the epiglottis |
lateral glossoepiglottic fold is located lateral to the valleculae epiglottica |
| lobe, frontal |
rostral to central sulcus |
contains prefrontal (emotions, personality) and precentral (primary and
secondary motor) areas |
| lobe, parietal |
separated from the frontal lobe by the central sulcus, separated from occipital
lobe by an imaginary line through the parieto-occipital sulcus |
contains the primary and secondary somatosensory areas |
| lobe, temporal |
separated from the frontal lobe by the lateral sulcus |
primarily concerned with hearing and memory/learning |
| lobe, occipital |
posterior to an imaginary line through the parieto-occipital sulcus |
contains the primary and secondary visual cortex |
| lobe, limbic |
a border (limbus = Latin for border) of cortical tissue surrounding the
third ventricle |
limbic lobe is comprised of: cingulate gyrus, parahippocampal gyrus, uncus
and other small portions of the adjacent cortex; it is the part of the brain
responsible for behavior and emotions |
| longitudinal fissure |
cleft located in the sagittal plane that separates the paired cerebral hemispheres |
also known as: longitudinal sulcus; it contains the falx cerebri |
| mamillary body |
part of the hypothalamus; a small spherical projection on the inferior surface
of the floor of the third ventricle posterior to the hypophysis |
mamillary body is involved with memory and learning |
| median aperture |
midline, irregular foramen draining the fourth ventricle posteroinferiorly
into the cerebellomedullary cistern |
also known as: foramen of Magendie |
| median glossoepiglottic fold |
fold of mucosa located between the base of the tongue and the epiglottis |
separates the paired valleculae epiglottica |
| medulla oblongata |
most caudal portion of the brainstem |
medulla oblongata is continuous with the spinal cord at the foramen magnum;
the upper portion forms the floor of the fourth ventricle; it is the site of
origin for cranial nerves VIII, IX, X, XI (cranial root), & XII; also known
as: myelencephalon |
| meninges |
three layers of connective tissue covering the brain and spinal cord; dura
mater, arachnoid mater, and pia mater |
meninges provide protection and nourishment of the brain, brainstem and
spinal cord |
| mesencephalon |
the portion of the brain that connects the forebrain and the hindbrain |
it contains the corpora quadrigemina and the cerebral aqueduct; also known as: midbrain |
| metencephalon |
the rostral part of the rhombencephalon |
comprised of: pons & cerebellum (Greek, metencephalon = after brain) |
| midbrain |
the portion of the brain that connects the forebrain and the hindbrain |
midbrain is the site of origin of cranial nerves III & IV; it contains the
cerebral aqueduct |
| myelencephalon |
the caudal part of the rhombencephalon |
myelencephalon is comprised of: medulla oblongata; medulla becomes continuous with the spinal cord at the level of the foramen magnum |
| nasolacrimal duct |
mucosa-lined duct connecting the medial angle of the eye with the nasal
cavity |
drains tears from the lacrimal sac to the inferior meatus of the nasal cavity |
| nasopharynx |
the portion of the pharynx located posterior to the posterior nasal apertures
and superior to the soft palate |
nasopharynx communicates; anteriorly with the nasal cavity through the choanae
and inferiorly with the oropharynx; it contains the torus tubarius, pharyngeal
recess and pharyngeal tonsil |
| notch, preoccipital |
a shallow notch in the inferior surface of the cerebral cortex (superior
to the cerebellum) as seen in lateral view |
a surface landmark for defining the border between the parietal and occipital
lobes |
| oropharynx |
the portion of the pharynx located posterior to the palatoglossal arches
of the oral cavity and inferior to the soft palate |
oropharynx communicates: anteriorly with oral cavity through oropharyngeal
isthmus (palatoglossal arch), superiorly with the nasopharynx through pharyngeal
isthmus (posterior margin of soft palate), inferiorly with the laryngopharynx
at the superior margin of epiglottis; it contains the palatine tonsil which
is located in the tonsilar bed (between the palatoglossal arch and the palatopharyngeal
arch) |
| olfactory bulb |
flattened, oval enlargement at the anterior tip of the olfactory tract |
olfactory bulb contains the olfactory cells which are the origin of the
axons that course through the olfactory tract; the olfactory nerve begins at
the bipolar olfactory cells in the nasal mucosa and courses through the cribriform
plate to the olfactory bulb |
| olfactory tract |
a ribbon-like nerve tract that courses from the olfactory bulb to the cerebral
cortex |
olfactory tract carries the sense of smell; it courses in the olfactory
sulcus |
| olive |
a elevation located lateral to the pyramid of medulla |
paired; the olives contain the inferior olivary nuclei |
| optic chiasm |
crossover point for the nasal fibers of both retinas |
lateral visual fields (medial retinal fibers) project to the contralateral occipital lobe (Greek, chiasm = two crossing lines) |
| optic tract |
the portion of the visual pathway between the optic chiasm and the brain |
visual system projects to the occipital lobe |
| palatoglossal fold |
fold of mucosa covering the palatoglossus m. |
palatoglossal fold marks the anterior boundary of the bed of the palatine
tonsil |
| palatopharyngeal fold |
fold of mucosa covering the palatopharyngeus m. |
palatoglossal fold marks the posterior boundary of the bed of the palatine
tonsil |
| parathyroid glands |
four small endocrine glands located on the posterior surface of the lateral
lobes of the thyroid gland |
two pair of glands that develop from the 3rd and 4th pharyngeal pouches;
they produce parathormone which is important in regulating serum calcium levels |
| parotid gland |
salivary gland located lateral and posterior to the mandibular ramus, beside
(para) the ear (oto) |
largest salivary gland; innervated by postganglionic parasympathetic fibers
from the otic ganglion via the auriculotemporal n. |
| parotid duct |
thick duct that crosses the superficial surface of the masseter m. |
parotid duct drains the parotid gland through cheek to the oral vestibule
near upper 2nd molar tooth |
| pharyngeal recess |
space located posterior to the torus tubarius in nasopharynx |
the pharyngeal tonsil is located in this region |
| pharynx |
the space posterior to the nasal cavity, oral cavity and larynx |
divided into 3 parts: nasopharynx, oropharynx and laryngopharynx; the airway
and the pathway of ingested foods and liquids cross at this location |
| pia mater |
delicate membrane that lies on surface of the brain and spinal cord |
"delicate mother", it is the most delicate of the meninges; this layer faithfully
follows all surface contours of the brain and spinal cord; pia mater has 2
specializations: denticulate ligament and filum terminale internum |
| pineal gland |
a knob-like projection from the roof of the diencephalon |
an endocrine gland; also known as: pineal body |
| piriform recess |
shallow depression located lateral to the aryepiglottic fold in the laryngopharynx |
the internal branch of the superior laryngeal n. is located immediately deep to the mucosa in this region; also known as: piriform fossa (Latin, piriform = pear shaped) |
| plica sublingualis |
fold of mucosa under the tongue which covers the sublingual gland |
also known as the sublingual fold (Latin, plica = fold) |
| pole, frontal |
the most anterior part of the cerebral hemisphere |
frontal pole is part of the frontal lobe |
| pole, temporal |
the most anterior part of the temporal lobe |
|
| pole, occipital |
the most posterior part of the cerebral hemisphere |
occipital pole is part of the occipital lobe; composed of primary visual
cortex |
| pons |
the anterior portion of the metencephalon |
pons is the site of origin of cranial nerves V, VI, VII & VIII; it forms part of the anterior wall of the fourth ventricle (Latin, pons = bridge) |
| posterior median sulcus |
midline furrow on the posterior surface of the spinal cord and medulla oblongata |
posterior median sulcus starts at the obex and continues throughout the
length of the spinal cord |
| pyramid |
an elevations on the anterior surface of the medulla oblongata |
paired; the pyramids are separated by the anterior median fissure; they
contain the pyramidal tracts |
| pyramidal decussation |
point of crossover of 80% the fibers of the corticospinal tracts; located
at lower levels of the medulla |
voluntary muscles of one side of the body are under the control of the contralateral
cerebral cortex |
| rima glottidis |
the opening between the vocal folds |
the glottis is the vocal fold plus the rima glottidis |
| salpingopharyngeal fold |
mucosal fold descending from the posterior margin of the torus tubarius |
salpingopharyngeal fold contains the salpingopharyngeus m. |
| spinal dura mater |
outermost covering of the spinal cord, it forms the dural sac containing
the spinal cord within vertebral canal |
dural sac ends at S2, coccygeal ligament (filum terminale externum) continues
inferiorly to attach to coccyx |
| subarachnoid space |
the space between the arachnoid mater and the pia mater |
subarachnoid space contains cerebrospinal fluid and spider web-like filaments |
| submandibular duct |
duct connecting the submandibular gland to the floor of the oral cavity |
submandibular duct drains the submandibular gland to the sublingual caruncle |
| submandibular gland |
salivary gland located beneath the mylohyoid m. in the submandibular triangle |
submandibular gland is innervated by postganglionic parasympathetic fibers
from the submandibular ganglion |
| sublingual caruncle |
a papilla on the lateral side of the sublingual frenulum of the tongue |
sublingual caruncles the site of the opening of the duct of the submandibular
gland |
| sublingual gland |
salivary gland located beneath the oral mucosa in the floor of mouth |
sublingual gland is located deep to the plica sublingualis; it drains onto
the floor of the oral cavity via multiple small ducts |
| sulcus, calcarine |
sulcus between the lingual gyrus and the cuneus |
primary visual cortex is both superior and inferior to it (Latin, sulcus = a furrow or ditch) |
| sulcus, central |
separates the frontal lobe from the parietal lobe; it separates the sensory
cortex from the motor cortex |
also known as: fissure of Rolando (Latin, sulcus = a furrow or ditch) |
| sulcus, longitudinal |
cleft located in the sagittal plane that separates the paired cerebral hemispheres |
it contains the falx cerebri; also known as: longitudinal fissure (Latin, sulcus = a furrow or ditch) |
| sulcus, precentral |
the sulcus anterior to the precentral gyrus |
in conjunction with the central sulcus, it defines the precentral gyrus (motor) (Latin, sulcus = a furrow or ditch) |
| sulcus, postcentral |
the sulcus posterior to the postcentral gyrus |
in conjunction with the central sulcus, it defines the postcentral gyrus (sensory) (Latin, sulcus = a furrow or ditch) |
| sulcus, lateral |
separates the frontal lobe and the temporal lobe |
the insula lies in the floor of this sulcus (Latin, sulcus = a furrow or ditch) |
| sulcus, olfactory |
sulcus that defines the lateral margin of the straight gyrus |
contains the olfactory bulb and tract (Latin, sulcus = a furrow or ditch) |
| sulcus, superior temporal |
sulcus between the superior and middle temporal gyri |
used to define the superior and middle temproal gyri (Latin, sulcus = a furrow or ditch) |
| sulcus, inferior temporal |
sulcus between the middle and inferior temporal gyri |
used to define the middle and inferior temporal gyri (Latin, sulcus = a furrow or ditch) |
| sulcus, parieto-occipital |
sulcus between the parietal and occipital lobes |
landmark used to define the borders of the parietal and occipital lobes
when viewing the cerebral hemisphere from a medial perspective |
| sulcus, cingulate |
the sulcus that lies superior to the cingulate gyrus |
defines the cingulate gyrus (Latin, sulcus = a furrow or ditch) |
| superior colliculus |
paired elevations of the midbrain tectum |
part of the corpora quadrigemina; important for reflex movements of the eye, head and neck (Latin, colliculus = a mound) |
| tectum |
the roof of the midbrain, formed by the superior and inferior colliculi;
located dorsal to the cerebral aqueduct |
also known as: quadrigeminal plate (Latin, tectum = roof) |
| tegmentum |
the collection of cells and nerve fibers located ventral to the ventricle
system in the midbrain, pons and medulla |
gives rise to the middle cerebellar peduncle (Latin, tegmentum = cover) |
| telencephalon |
rostral part of prosencephalon/forebrain |
comprised of: cerebral hemispheres and basal ganglia; contains the lateral ventricles (Greek, telencephalon = end brain) |
| tentorium cerebelli |
tent-like sheet of dura mater covering the superior surface of the cerebellum,
oriented somewhat transversely |
the midbrain passes through the tentorial notch (Latin, tentorium = tent) |
| thalamus |
an egg-shaped collection of nuclei forming part of the lateral wall of the
third ventricle |
thalamus distributes information to appropriate areas of the cerebral cortex |
| thyroid cartilage |
anterior cartilage of the larynx; formed by two flat plates that fuse anteriorly
in the midline to form the laryngeal prominence |
thyroid cartilage is connected: above to the hyoid bone via the thyrohyoid
membrane; below to the cricoid cartilage via the inferior horn; posteriorly
to the paired arytenoid cartilages via the vocal ligaments and thyroartenoid
mm.; posteriorly to the epiglottic cartilage via the thyroepiglottic ligament;
under the action of the cricothyroid m. the thyroid cartilage tilts forward
to increase tension on the vocal ligament and raise the pitch of the voice |
| thyroid gland |
a large endocrine bland that lies anterolateral to the lower part of the
larynx and upper trachea |
thyroid gland consists of two lateral lobes joined across the midline by
the isthmus; it may have a pyramidal lobe extending superiorly near midline
which is a remnant of development that marks its route of migration from a
primordium that originates at the foramen cecum or the tongue; thyroid gland
is supplied by superior and inferior thyroid aa.; it produces thyroxin |
| thyroid isthmus |
constricted midline connection between the lateral lobes of the thyroid
gland |
thyroid isthmus lies anterior to tracheal rings 2-4 |
| torus tubarius |
mucosal fold covering the anteromedial end of the auditory tube cartilage |
torus tubarius projects toward the midline from the lateral wall of the nasopharynx (Latin, torus = a knot) |
| trachea |
main airway that lies anterior to the esophagus |
trachea extends from vertebral level C6 to the level of the T4/5 intervertebral
disc; superiorly it is connected to the cricoid cartilage via the cricotracheal
ligament; it bifurcates into two primary bronchi |
| uncus |
portion of the cerebral cortex on the medial side of the parahippocampal
gyrus and overlying the amygdala |
uncus is located near the free edge of the tentorium cerebelli; it contains the olfactory cortex (Latin, uncus = a hook) |
| vallate papilla |
the largest type of papilla located on the dorsum of the tongue; a total
of 8-12 in number arranged along the anterior border of the sulcus terminalis |
vallate papillae possess taste buds in a circular sulcus; also known as:
circumvallate papillae |
| valleculae epiglottica |
fossa located between the base of the tongue and the epiglottis |
paired; each of the valleculae epiglottica is located between the median
glossoepiglottic fold and the lateral glossoepiglottic fold |
| ventricle, lateral |
paired spaces within the cerebral hemispheres |
lateral ventricles drain cerebrospinal fluid to the third ventricle via
the interventricular foramina (of Monroe) |
| ventricle, third |
a midline space within the diencephalon between the paired dorsal thalami
and the hypothalamus |
third ventricle communicates rostrolaterally with paired lateral ventricles
via interventricular foramina, communicates posteroinferiorly with fourth ventricle
via cerebral aqueduct |
| ventricle, fourth |
midline space between the cerebellum posteriorly and the pons and upper
medulla anteriorly |
fourth ventricle communicates anterosuperiorly with the third ventricle
via the cerebral aqueduct; it drains CSF via the median aperture and the lateral
apertures |
| vestibular fold |
fold of mucosa located between the laryngeal vestibule and the laryngeal
ventricle |
also known as: false vocal fold |
| vocal folds |
fold of mucosa covering the vocal ligament and the thyroepiglottic muscle
(vocalis part) |
located inferior to the laryngeal ventricle; also known as: true vocal fold |
| vocal ligament |
an elastic band of connective tissue located in the vocal fold |
paired; each vocal ligament is connected to the inner surface of the thyroid
cartilage anteriorly and to the vocal process of the arytenoid cartilage posteriorly;
vocal ligament is the thickened superior margin of the conus elasticus; vibration
creates sound; adducted by the actions of the arytenoid mm. and lateral cricoarytenoid
m.; abducted by the action of the posterior cricoarytenoid m. |
