PASS 610 - Exam 3 - Pelvis & Pelvic Viscera

You are observing a doctor perform an abdominal hysterectomy. He notes that it is vital to protect the ureter which is found in the base of the: A) mesometrium B) mesovarium C) mesosalpinx D) round ligament of the uterus E) suspensory ligament of the ovary

A) Mesometrium The mesometrium is the part of the broad ligament of the uterus that attaches the body of the uterus to the pelvic wall. The ureters pass through the base of the mesometrium as they travel to reach the bladder. See Netter Plate 346 for a picture of this relationship. The mesovarium is the part of broad ligament that forms a shelf-like fold supporting the ovary. The suspensory ligament of the ovary, which conveys the ovarian vessels, lymphatics, and nerves to and from the ovary, constitutes the lateral part of the mesovarium of the broad ligament. The mesosalpinx is the part of broad ligament that supports the uterine tube. Finally, the round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus. It lies in the mesometrium, and it is continuous with the ovarian ligament.

After agreeing to have no more children, a man and his wife decided he should have a vasectomy. What structure would then be surgically ligated? A) Ductus deferens B) Ejaculatory duct C) Epididymis D) Fossa navicularis E) Seminal vesicle

A) ductus deferens In a vasectomy, the ductus deferens is ligated or excised. This means that the fluid that is then ejaculated from the seminal vesicles, prostate, and bulbourethral glands has no sperm. The sperm simply degenerate in the epididymis and the proximal ductus deferens. It would not be a good idea to ligate the ejaculatory duct or the seminal vesicle because that might compromise the patient's ability to ejaculate. Just remember, another name for the ductus deferens is the vas deferens, so it make sense that the procedure to ligate this structure is called a vasectomy.

Benign hyperplasia (excessive growth of cells) of which part of the male reproductive system would be most likely to interfere with the passage of urine? A) Periurethral Zone of the Prostate B) Central Zone of the Prostate C) Peripheral Zone of the Prostate D) Ejaculatory Duct E) Seminal Vesicle

A) periurethral zone of the prostate Remember that the prostatic urethra travels through the prostate gland. So, if the periurethral zone of the prostate hypertrophied, the nearby prostatic urethra would be occluded. The central and peripheral zones of the prostate are not as close to the urethra. If they enlarged, they would not restrict the flow of urine quite as much. The ejaculatory duct is the duct formed once the ductus deferens joins with the duct of the seminal vesicle. It passes through the prostate gland, but its enlargement would have no effect on the prostate or the urethra. Finally, the seminal vesicle is a sac on the posterior surface of the bladder which is superior to the prostate gland. It produces seminal fluid, and changes in the seminal vesicle should not alter the flow of urine.

Which skeletal feature would you consider to be most characteristic of the female pelvis? A) Subpubic angle of 90 degrees or greater B) Marked anterior curvature of the sacrum C) Tendency to vertical orientation of the iliac bones D) Prominent medial projection of the ischial spines

A) subpubic angle of 90 degrees or greater There are four major differences between the male and female pelvis. First, the subpubic angle and pubic arch are greater in the female pelvis than in the male pelvis. This is why A is correct-- females often have a subpubic angle of 90 degrees or greater. A second difference between the female and male pelvis is that the pelvis inlet for females is rounded, while for males it is heart shaped. Third, the pelvic outlet for females is larger than in males. Finally, the female pelvis has iliac wings that are more flared than in males.

During a hysterectomy and an oophorectomy, the uterine and ovarian vessels must be ligated. These vessels can be found in which ligaments? A) Broad and ovarian B) Broad and suspensory C) Round and ovarian D) Round and suspensory E) Suspensory and ovarian

B) Broad and suspensory The uterine vessels are found in the inferior portion of the broad ligament, while the ovarian vessels are found in the suspensory ligaments of the ovaries. The suspensory ligaments of the ovaries are peritoneal folds covering ovarian arteries, veins, nerves, and lymphatics as the structures pass over the pelvic brim to reach the ovary. The ovarian ligament proper is a round cord which attaches the ovary to the uterus, just below the entrance of the uterine tube into the uterus. The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus--it traverses the inguinal canal and it is found in the broad ligament.

An elderly patient notices red blood in his stool. As part of his examination, you insert a proctoscope (sigmoidoscope) through his anal canal. As you pass the scope superiorly through the rectum, the most prominent features to be seen are: A) longitudinal muscle bands B) tenia coli C) transverse rectal folds D) rectovesical pouches E) haustra

C) Transverse rectal folds The rectum features three transverse rectal folds--these folds would be the most prominent features that you would see in the interior of the rectum if you were using a proctoscope. The tenia coli are the three bands of longitudinal muscle seen on the surface of the colon--the pattern of the teniae coli changes as the transition from sigmoid colon to rectum occurs. The sigmoid colon, like the rest of the colon, has three longitudinal muscular bands. These coalesce into two bands, anterior and posterior, on the rectum. However, none of these longitudinal muscle layers would be visible from the interior of the rectum. The rectovesical pouch is a peritoneal fold reflecting from the rectum to the posterior wall of the bladder in the male. Remember--females do not have the rectovesicular pouch. Instead, they have the vesicouterine and rectouterine pouches. Finally, the haustra are multiple pouches in the wall of the large intestine--they are not found in the rectum.

The expanded region of the lower rectum, where fecal matter is retained, is known as the: A) Anal columns B) Anal sinuses C) Ampulla D) Transverse folds

C) ampulla The ampulla is an expanded part of the lower rectum that stores feces. The transverse rectal folds are three folds in the ampulla which help to support fecal mass, but they are not the same as the actual region that stores the feces. Anal columns are longitudinal folds of mucosa over rectal vessels. They are found on the inner wall of the anal canal. Anal valves are folds of mucosa that join the anal columns at their inferior ends and create spaces between the wall and the valves known as anal sinuses.

The prostate gland: A) encircles the urethra B) is well imaged using an intravenous urogram C) is partially intraperitoneal D) contains upper, middle and lower lobes

A) Encircles the urethra The prostate gland encircles the urethra. It circles around the first part of the urethra, the prostatic urethra. This is why urinary retention is one symptom of prostatic hypertrophy--if the prostate is enlarged, it may close around the urethra, occluding this passage and preventing urine from exiting the bladder. The prostate would not be imaged using an intravenous urogram. In an intravenous urogram, a patient is given IV contrast, and radiographic images are taken as the contrast is excreted, passing through the kidneys, ureters, and bladder. Since the prostate is not part of this excretory pathway, it would not be viewed through this method. The prostate gland is completely extraperitoneal. Remember: the rectovesicular pouch, a fold of peritoneum that hangs between the bladder and rectum, is the lowest extent of the peritoneal cavity in males . But, the prostate is found on the posterior side of the bladder, below the point where the peritoneal membrane created this fold. So, it is an extraperitoneal organ. Finally, the lobes of the prostate are: anterior, posterior, lateral, and middle.

During a hysterectomy, care must be taken in ligation of the uterine vessels because they cross the _________ superiorly. A) ureter B) round ligament of the uterus C) ovarian artery D) lumbosacral trunk E) inferior hypogastric plexus

A) Ureter The uterine vessels cross over the ureter as the ureters pass through the base of the mesometrium. Remember--the ureters must travel through the mesometrium to reach the base of the bladder. The relationship between the ureter and the uterine vessels is very important--you should remember this! The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majora and the uterus. It is found in the broad ligament, but it is superior to the ureter and the uterine vessels. The ovarian vessels are contained in the suspensory ligament of the ovary. The lumbosacral trunk is part of the ventral primary ramus of L4 united with the ventral primary ramus of L5--it contributes to the formation of the sacral plexus. The inferior hypogastric plexus lies between the pelvic viscera and the pelvic wall--it supplies sympathetic innervation to the vascular smooth muscle of pelvic vessels and parasympathetic innervation to the smooth muscles of the pelvis.

A 64-year-old woman was diagnosed as having carcinoma of the distal gastrointestinal tract. At surgery, lymph nodes from the sacral, internal iliac and inguinal lymph node groups were removed and sent to pathology for study. Only the superificial inguinal nodes contained cancerous cells. In which part of the GI tract was the tumor localized? A) cutaneous portion of anal canal B) distal rectum C) mucosal zone of anal canal D) pectinate line of anal canal E) proximal rectum

A) cutaneous portion of the anal canal The pectinate line is more than the line where the mucosal lining of the anal canal changes to skin. It is also a key dividing point for the flow of lymph in the anal canal. Above the pectinate line, lymph flows to the inferior mesenteric and internal iliac lymph nodes. Below the pectinate line, lymph flows to the superficial inguinal lymph nodes. So, the pathology report tells you that the tumor must be somewhere below the pectinate line since the superficial inguinal lymph nodes are the only nodes involved. The only answer representing a tumor below the pectinate line is A, the cutaneous portion of the anal canal. The proximal and distal rectum represents a space far above the pectinate line, and the mucosal zone of the anal canal is, by definition, above the pectinate line. At the pectinate line itself, lymph should be flowing to all the sets of nodes, and it would be unlikely that a tumor at the pectinate line would involve only the superficial inguinal lymph nodes.

Which structure is NOT found within the true pelvis? A) Femoral nerve B) Hypogastric nerve C) Internal pudendal artery D) Obturator artery E) Pelvic splanchnic nerves

A) femoral nerve To answer this question, you need to understand what the true pelvis is. The true pelvis is the area beneath the pelvic brim (pelvic inlet), where the pelvic viscera are located. The false pelvis is the area above the pelvic brim, bounded by the iliac blades. Now, you just need to think about the structures listed and determine which ones are in which location. The femoral nerve is the structure that is not in the true pelvis. After coming off the lumbar plexus with contributions from L2, 3, and 4, the femoral nerve runs along the border between the psoas major muscle and the iliacus to travel into the lower limb. It never descends below the pelvic brim, so it is not in the true pelvis. Hypogastric nerves connect the superior and inferior hypogastric plexuses. Since the inferior hypogastric plexus is lying between the pelvic viscera and the pelvis wall, in the true pelvis, the hypogastric nerves should also be in the true pelvis. The internal pudendal artery is a branch of the anterior division of the internal iliac artery. It lies in the true pelvis and supplies blood to the perineum. The obturator artery is a branch of the anterior internal iliac artery or, if it is the aberrant obturator, the inferior epigastric artery. It is in the true pelvis, and exits the pelvis through the obturator foramen. The pelvic splanchnic nerves represent the sacral portion of the craniosacral outflow (parasympathetic) of the autonomic nervous system. They come from the ventral rami of the second, third, and fourth sacral nerves. So, that puts them in the true pelvis, too.

Which of the following is considered a part of the broad ligament? A) Mesovarium B) Ovarian ligament C) Round ligament of the uterus D) Suspensory Ligament of the ovary E) Uterosacral ligament

A) mesovarium The mesovarium, mesometrium, and mesosalpinx are the three peritoneal sections that create the broad ligament. The mesosalpinx covers the uterine tube and hangs below it to meet with the mesovarium. The mesovarium covers the ovary and ovarian ligament. It extends posteriorly from the mesosalpinx like a shelf. The mesometrium makes up the rest of the broad ligament. The ovarian ligament is located in the broad ligament but is not part of the broad ligament. It is a round cord that attaches the ovary to the uterus just below the point where the uterine tube enters the uterus. The round ligament of the uterus reaches the lateral surface of the uterus below the uterine tube. It is continuous with the ovarian ligament and it holds the fundus of the uterus forward. The suspensory ligaments of the ovary are peritoneal folds that cover the ovarian neurovascular supply as these vessels pass over the pelvic brim to reach the ovary. Finally, the uterosacral ligament connects the isthmus of the uterus to the sacrum. It is important for the support of the uterus, and it is found in the rectouterine fold.

Which structure is outlined with contrast on a CT using intraperitoneal contrast material? A) Ovary B) Prostate C) Rectum D) Seminal Vesicles E) Vagina

A) ovary The ovary is entirely covered by a layer of peritoneum called the mesovarium. The mesovarium, along with the mesometrium and the mesosalpinx, creates the broad ligament. Because the ovary is completly encased in peritoneum, it would be outlined on a CT with intraperitoneal contrast material. The prostate, seminal vesicles and vagina are located below the rectovesicular pouch or rectouterine/vesicouterine pouches. So, they are not associated with the peritoneal cavity and would not be seen on the CT scan. Although peritoneum drapes over the rectum, forming the rectovesicular fold in males and the rectouterine fold in females, the rectum would not be clearly outlined by the intraperitoneal contrast since it is not covered by peritoneum on all sides.

Structures within the lower gastrointestinal tract specialized for physical support of fecal material are the: A) Transverse rectal folds B) Circular folds C) Anal valves D) Anal columns

A) transverse rectal folds There are usually three transverse rectal folds in the lower rectum. These are specializations of the circular layer of musculature that are designed to support fecal mass. Although circular folds is somewhat descriptive of the transverse rectal folds, this is not the best answer. Anal columns are longitudinal folds of mucosa over rectal vessels. They are found on the inner wall of the anal canal. Anal valves are the folds of mucosa that join the anal columns at their inferior ends.

A female patient comes to your office with lower abdominal pain. She missed her last menses and her pregnancy test is positive. Ultrasound imaging reveals a cyst-like structure in the right uterine tube which you feel may be a tubal pregnancy. In order to confirm your diagnosis and to remove the tubal embryo, you can gain access to the patient's lower pelvic cavity by passing a culdoscope through the vagina and the: A) vesicouterine pouch B) posterior fornix C) cervix D) isthmus E) ampulla

B) Posterior fornix In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity and remove the embryo. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder. The cervix is the inferior end of the uterus which connects the uterus to the vagina. The isthmus and ampulla are parts of the uterine tube--the isthmus is the constricted part of the uterine tube nearest the uterus, and the ampulla is the dilated region that connects the infundibulum with the isthmus.

In a CT scan of the pelvis, the uterus is located: A) posterior to the bladder and rectum B) posterior to the bladder and anterior to the rectum C) anterior to the bladder and rectum D) anterior to the bladder and posterior to the rectum

B) Posterior to the bladder and anterior to the rectum In the female pelvis, the bladder is the most anterior organ; the uterus is posterior to the bladder, and the rectum is posterior to the bladder and uterus. See Netter Plate 337 for a picture.

During a vasectomy, the ductus deferens is ligated in the superior part of the scrotum. Two months following this sterilization procedure, the subsequent ejaculate contains: A) Prostatic fluid only B) Seminal fluid and prostatic fluid C) Sperm only D) Sperm and seminal fluid E) Sperm, seminal fluid, and prostatic fluid

B) Seminal fluid and prostatic fluid The ductus deferens carries sperm from the tail of the epididymis to the ejaculatory duct. When this cord is ligated, sperm cannot enter the ejaculatory duct, so there will be no sperm in the subsequent ejaculate. The seminal vesicles and prostate also contribute fluid to the ejaculate. However, ligating the ductus deferens will not interrupt the path of seminal fluid or prostatic fluid. So, the ejaculate will still contain both of these fluids.

Which pair of structures does NOT differentiate from comparable embryonic structures in the male and female? A) Bulb of corpus spongeosum and vestibular bulb B) Shaft of penis and labia majora C) Glans of penis and glans of clitoris D) Crus of corpus cavernosum penis and crus of corpus cavernosum clitoris

B) Shaft of penis and labia majora The shaft of the penis is an analog of the shaft of the clitoris, while the labia majora is derived from the same embryonic structures as the scrotum. The other three answer choices list structures that come from comparable embryonic structures in the male and female. See Netter Plate 389 for a picture of the homologous structures in males and females!

The male pelvis tends to differ from the female pelvis in that the male pelvis often has a: A) larger pelvic inlet B) smaller subpubic angle C) straighter sacral curvature D) larger pelvic outlet E) rounder pelvic inlet

B) Smaller subpubic angle There are four major differences between the male and female pelvis. First, the subpubic angle and pubic arch are greater in the female pelvis than in the male pelvis. This is why B is correct-- the male pelvis has a smaller subpubic angle than the female pelvis. A second difference between the female and male pelvis is that the pelvic inlet for females is rounded, while for males it is heart shaped. Third, the pelvic outlet for females is larger than in males. Finally, the female pelvis has iliac wings that are more flared than in males.

Under normal conditions, fertilization occurs in which part of the female reproductive tract? A) Infundibulum of the Uterine Tube B) Ampulla of the Uterine Tube C) Isthmus of the Uterine Tube D) Uterine Lumen E) Cervical Canal

B) ampulla of the uterine tube Fertilization normally takes place in the ampulla of the uterine tube. This is the middle segment of the uterine tube, and it is the longest and widest segment. The infundibulum is the funnel-shaped distal end of the uterine tube, and the isthmus is the narrowest part of the uterine tube which connects directly to the uterus. The uterine lumen is the site of implantation, not fertilization. Finally, the cervical canal is the pathway out of the uterus at its inferior end-- it would not be an appropriate site for fertilization or implantation.

Which of the following does not conduct spermatozoa? A) Ampulla of the ductus deferens B) Duct of the seminal vesicle C) Epididymis D) Prostatic Urethra

B) duct of the seminal vesicle The duct of the seminal vesicle carries seminal fluid, a basic fluid containing fructose. The contents of the seminal fluid buffers the acid in the vagina and provides nutrients for sperm. The duct of the seminal vesicle joins with the ampulla of the ductus deferens (which is carying sperm) to form the ejaculatory duct. This is the first place where seminal fluid mixes with sperm. Sperm is first formed in the seminiferous tubules. They then travel from the head to the tail of the epididymis, through the ductus deferens, into the ejaculatory duct where they mix with seminal fluid, into the prostatic urethra, through the rest of the urethra, and then out the penis. So, all of the other answer choices are places that are important for the passage of sperm.

A structure which is homologous to the male scrotum: A) Labia minora B) Labia majora C) Glans D) Shaft of corpus cavernosum

B) labia majora The labia majora and scrotum are homologous structures. The labia minora is the female counterpart of the pentscrotal raphe. The glans of the clitoris and glans of the penis are homologous structures. Finally, the shaft of the corpus cavernosum in the female is the shaft of the clitoris, which is homologous to the shaft of the penis.

The part of the uterine wall which is not shed during menstruation is the: A) Endometrium B) Myometrium C) Mesometrium D) Cervical mucosa E) Rugae

B) myometrium This question is phrased in a slightly tricky way, so it's important to break it down before looking at the answers. There are two things to think about here. First, you need to decide if a structure is part of the uterus. If it is part of the uterus, then you need to decide if it is shed during menstruation. The correct answer will be a structure that is part of the uterus but is not shed during menstruation. Answers about structures that are not shed during menstruation because they are not part of the uterine wall are incorrect. The myometrium is our correct answer. It is the middle muscular component of the uterine wall and it is not shed during menstruation. The endometrium is the inner mucosal coat of the uterus. It exhibits many characteristic changes during the menstrual cycle and all but its stratum basalis is shed during menstruation. The mesometrium is the mesentary of the uterus which forms the major part of the broad ligament of the uterus. It is not even part of the uterine wall, so it's not the answer to look for. Cervical mucosa lines the cervix, which is the inferior portion of the uterus. This mucosa is shed during menstruation. Finally, the uterus does not have rugae - rugae are the folds found in the lining of the vagina (and stomach).

The part of the broad ligament giving attachment and support to the uterine tube is the: A) mesometrium B) mesovarium C) mesosalpinx D) round ligament

C) Mesosalpinx The mesosalpinx is the part of broad ligament that supports the uterine tube. The mesosalpinx extends inferiorly to meet the root of the mesovarium; it attaches the uterine tube to the mesometrium. The mesometrium is the part of the broad ligament below the junction of the mesosalpinx and the mesovarium; it attaches the body of the uterus to the pelvic wall. The mesovarium is the part of broad ligament that forms a shelf-like fold supporting the ovary--it attaches the ovary to the mesometrium and mesosalpinx. The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus. It is found in the broad ligament, and it traverses the inguinal canal.

A female patient is found to have an ectopic (tubal) pregnancy (embryo develops in the uterine tube). In order to gain access to the peritoneal cavity endoscopically to remove the embryo, the instrument can be passed into the vagina and through the: A) anterior fornix B) cervix C) posterior fornix D) retropubic space E) vesicouterine pouch

C) Posterior fornix In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity and remove the embryo. Take a look at Netter Plate 337 for a picture of this relationship. Entering the anterior fornix of the vagina would not allow a surgeon to enter the peritoneal cavity. The cervix is the inferior portion of the uterus which connects the uterus to the vagina--passing through the cervix would allow the surgeon to enter the uterus, but not the peritoneal cavity. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder.

A female patient is found to have an ectopic (tubal) pregnancy. In order to gain access to the peritoneal cavity endoscopically to remove the tubal embryo, the instrument can be passed through the posterior fornix of the vagina piercing into the: A) external os B) internal os C) rectouterine pouch D) rectovesical pouch E) vesicouterine pouch

C) Rectouterine pouch In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. This means that an incision made through the posterior fornix of the vagina will allow a surgeon to enter the rectouterine pouch of the peritoneal cavity to remove the embryo. Take a look at Netter Plate 337 for a picture of this relationship. The vesicouterine pouch is a fold of peritoneum reflected from the uterus onto the posterior margin of the superior surface of the bladder--it helps to separate the uterus from the bladder. The rectovesicular pouch is only found in males--it is a peritoneal fold reflecting from the rectum to the posterior wall of the bladder. The external os of the cervix is the part of the cervix between the vagina and the cervical canal; the internal os of the cervix is the part of the cervix between the uterus and the cervical canal. See Netter Plate 346 for a picture of these osses.

A 27-year-old woman is examined by her gynecologist. Upon rectal examination, a firm structure, directly in front of the rectum in the midline, is palpated through the anterior wall of the rectum. This structure is the: A) bladder B) body of uterus C) cervix of uterus D) pubic symphysis E) vagina

C) cervix of the uterus The cervix of the uterus is anterior to the rectum. Since the cervix is the inferior part of the uterus that is protruding into the vagina, it should feel like a firm structure upon palpation. The bladder is the most anterior organ in the pelvis, in front of the uterus and rectum. So, the bladder would not be directly in front of the anterior wall of the rectum. The body of the uterus lies upon the bladder, so it is too far in front of the anterior rectal wall to be palpated. The pubic symphysis is the joint connecting the two pubic bones. It forms the anterior boundary of the pelvis, and would be too far forward to palpate through the rectum. Although the vagina is directly anterior to the rectum, it would not feel like a distinct and firm structure upon palpation.

During the course of surgery for benign prostatic hypertrophy (benign enlargement of the prostate tissue which occludes the prostatic urethra) an electrical cutting device is inserted into the penile, then prostatic urethra, to remove the hypertrophic tissue. The posterior wall of the prostatic urethra is by necessity removed as well. Which part of the male seminal tract may also be partially removed? A) duct of seminal vesicle B) ductus deferens C) ejaculatory duct D) fossa navicularis E) seminiferous tubule

C) ejaculatory duct The ejaculatory duct travels through the prostate and opens into the prostatic urethra. So, it is likely that this duct might get removed or damaged during the surgery. The duct of the seminal vesicle and the ductus deferens are the two ducts that join to make the ejaculatory duct. They both lie on the posterior surface of the bladder and would not be interrupted by the surgery. The fossa navicularis is a dilation in the penile urethra. It would not be harmed by surgery in the prostatic urethra. Finally, the seminferous tubules are the tubules in the testes where sperm are formed.

The extension of the vaginal lumen around the intravaginal part of the uterine cervix is the: A) Cervical canal B) Uterine lumen C) Fornix D) Rectouterine Pouch E) Uterovesical Pouch

C) fornix The cervix is the inferior end of the uterus that projects into the vagina. This means that the vagina comes up and wraps around the cervix, creating the vaginal fornix. There are multiple fornices at the top of the vagina: anterior, posterior, and lateral. The cervical canal is the passageway through the cervix to the vagina. The uterine lumen is the hollow center of the uterus. The rectouterine and uterovesicular pouches are two peritoneal folds found in the pelvic cavity. The rectouterine pouch is a peritoneal fold extending across the floor of the pelvic cavity from the sacrum (beside the rectum) to the uterus. The uterovesicular pouch is a peritoneal fold extending from the uterus to the bladder.

Lymphatic drainage of the terminal portion of the gastrointestinal tract may flow initially into either the superficial inguinal nodes or the pararectal nodes, depending upon whether the lymph is formed above or below the: A) Anorectal Junction B) Muscular Sling of the Puborectalis Muscle C) Pectinate Line D) White Line E) Cutaneous Zone

C) pectinate line The pectinate line is the place where the lining of the anal canal changes from skin to mucosa. It is also a landmark that divides the lymphatic drainage, vascular supply, and innervation of the anal canal. Lymph coming from structures above the pectinate line drains to the inferior mesenteric lymph nodes or the internal iliac nodes. Lymph from structures below the pectinate line travels to the superficial inguinal lymph nodes. As far as vasculature and nerves go... Superior to the pectinate line, arterial blood comes from the superior rectal artery and drains to the portal system through the superior rectal veins. This area is innervated by the inferior hypogastric plexus (autonomic innervation). Inferior to the pectinate line, blood comes from the inferior rectal arteries and is drained into the caval system. Innervation here comes from the inferior rectal nerves (somatic innervation). The anorectal junction is the point where the rectal ampulla narrows due to a U-shaped sling created by the puborectalis muscle. This area is superior to the pectinate line. The white line is a transitional area inferior to the pectinate line that represents some subtle changes as the mucosal lining becomes "regular" skin. Finally, the cutaneous zone is the area of skin at the very end of the rectum.

Which of the following would be most likely to be damaged by a Stab Wound into the ischiorectal (ischioanal) fossa 2 cm lateral to the anal canal? A) Crus of the Penis B) Perineal Body C) Pudendal Nerve D) Inferior Rectal Artery E) Vesicular Bulb

C) pudendal nerve The pudendal nerve is found about 2 cm lateral to the anal canal. Therefore, it is the structure most likely to be damaged by the Stab Wound. The crus of the penis is the lateral part of the corpus cavernosum found at the base of the penis. It is anterior, not lateral, to the anal canal. The perineal body is a structure found in the female only--it is a fibromuscular mass found in the plane between the anal canal and the perineal membrane that serves at the convergence of several muscles. It is anterior to the anal canal. The inferior rectal artery is a branch of the internal pudendal artery that delivers blood to the inferior part of the rectum. It would not be injured by the stabbing because it is located on the surface of the rectum, not 2 cm lateral to the anal canal. Finally, the vesicular bulb is a structure of erectile tissue located on either side of the vestibule of the vagina, attached to the perineal membrane. So, it would be anterior to the site of the stabbing.

The most inferior extent of the peritoneal cavity in the female is the: A) Pararectal fossa B) Paravesical fossa C) Rectouterine pouch D) Rectovesical pouch E) Vesicouterine pouch

C) rectouterine pouch Remember: The rectouterine and vesicouterine pouches are the two pouches created by draping the peritoneum over the pelvic organs. These pouches are the two lowest extents of the peritoneal cavity, so to answer this question, you just need to decide which one goes lower. Since the uterus is folded over the bladder, the rectouterine pouch can extend to a slightly lower level than the vesicouterine pouch, which makes C the correct answer. The pararectal fossa is formed by lateral reflections of perineum over the superior one third of the rectum; this space gives the rectum room to fill with feces. The paravesicular fossa is a space near the bladder that allows the bladder to expand. Why is the rectovesicular pouch incorrect? It's only found in males, not females! (But, if the question had asked about males, the rectovesicular pouch would have been the correct answer.)

The prostate is often imaged using an ultrasound transducer placed in which location? A) Penis B) Perineum C) Rectum D) Urethra E) Urinary Bladder

C) rectum The prostate is located on the posterior side of the bladder. Since the rectum is behind the bladder and prostate, you can image the prostate by placing an ultrasound transducer in the rectum and pressing it against the anterior wall. Then, the ultrasound transducer will be against the prostate gland.

During a hysterectomy, the uterine vessels are ligated. However, the patient's uterus continues to bleed. The most likely source of blood still supplying the uterus is from which artery? A) Inferior vesical B) Internal pudendal C) Middle rectal D) Ovarian E) Superior vesical

D) Ovarian The ovarian artery has branches which supply the uterus. In fact, this artery anastomoses with the uterine artery. So, if the uterus is still bleeding after ligating the uterine artery, the ovarian artery is probably supplying the uterus. The inferior vesical artery supplies the inferior part of the bladder--it anastomoses with the middle rectal artery. The internal pudendal artery supplies blood to the perineum. The middle rectal artery supplies blood to the rectum. The superior vesical artery supplies blood to the superior bladder.

The rectouterine pouch is the lowest extent of the female peritoneal cavity. At its lowest, it provides a coat of peritoneum to a portion of the: A) urinary bladder B) urethra C) uterine cervix D) vagina

D) Vagina In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. At its lowest extent, the rectouterine fold is draped over the posterior fornix of the vagina. This means that surgeons can make an incision in the posterior fornix of the vagina and enter the rectouterine pouch to harvest eggs from the ovaries or remove an ectopic pregnancy. Take a look at Netter Plate 337 for a picture of this relationship.

Which of these features of the anal canal serves to indicate the point where the mucosal covering of the gastrointestinal tract ends and a skin-like covering begins? A) Mucosal zone B) White line C) Transitional zone D) Pectinate line

D) pectinate line The pectinate line is the line of transition between the mucosal lining of the anal canal and the skin lining of the anal canal. So, this is the point where the mucosal zone ends and the skin begins. The white line is a transitional zone between the pectinate line and "regular" skin where there are some more subtle changes in the epithelial lining of the anal canal. But the pectinate line is the line that demarcates the major transition from mucosal lining to skin.

A structure which takes the form of a hood anterosuperior to the clitoris: A) Frenulum of the clitoris B) Labia majora C) Labia minora D) Prepuce

D) prepuce The prepuce is a fold of smooth skin that extends over the glans clitoris. It is formed by the joining of the anterior divisions of the labia minora. The frenulum of the clitoris is a small fold found posterior to the clitoris. It is formed by the joining of deeper, posterior, divisions of the labia minora. The labia majora are fat-filled elevations of skin lying on each side of the vestibule of the vagina. The labia minora are smaller folds of skin lying medial to the labia majora. They extend posteriorly and inferiorly from the clitoris.

Which structure is found only in males? A) Anterior recess of ischoianal fossa B) Genital Hiatus C) Ischiocavernosus muscle D) Rectovesical pouch E) Sphincter urethrae muscle

D) rectovesicular pouch The rectovesicular pouch is a reflection of the peritoneum between the rectum and the bladder. It can only be found in males because females have the uterus sitting between the rectum and the bladder. This means that females have two pouches created by reflections of peritoneum draped over the pelvic viscera: the rectouterine and vesicouterine pouches. The ischioanal fossa is the fat filled space located lateral to the anal canal and inferior to the pelvic diaphragm. It has an anterior recess that extends superior to the perineal membrane and sphincter urethrae muscle, and it is found in both males and females. The genital hiatus is also found in both sexes--it is the place where the urethra/vagina and anus exit the pelvic diaphragm. The ischiocavernosis muscle compresses the corpus cavernosum of the penis or clitoris. Finally, the sphincter urethrae encircles and compresses the urethra in both sexes.

A malignant tumor in the cutaneous zone of the anal canal would most likely metastasize (spread) to which group of lymph nodes? A) Inferior mesenteric B) Pararectal C) Sacral D) Superficial inguinal

D) superficial inguinal lymph nodes Remember, the pectinate line (the line in the anus where mucosa changes to skin) is the dividing line for lymphatic drainage. Structures above the pectinate line drain into the inferior mesenteric and internal iliac nodes. Structures below the pectinate line drain into the superficial inguinal nodes. Since the tumor is in the cutaneous (skin) region of the anal canal, it is going to be drained by the superficial inguinal nodes. This means that these nodes would be the first site of metastases.

Which structure does NOT form part of the boundary defining the trigone of the bladder? A) Interuteric crest B) Left Ureteric Orifice C) Right Ureteric Orifice D) Urachus E) Urethral Orifice

D) urachus The trigone of the bladder is bounded by the openings of the left and right ureteric orifices superolaterally, the interureteric crest between the openings of the ureters and the internal urethral orifice inferiorly. The urachus is the structure that joins the apex of the fetal bladder to the umbilicus. After birth, it becomes the median umbilical ligament.

The prostate gland: A) Contains upper, middle and lower lobes B) Encircles the urethra C) Is well imaged radiologically using an intravenous urogram D) Is extraperitoneal E) B and D

E) B and D There are two true statements here. First, the prostate gland encircles the urethra. It circles around the first part of the urethra, the prostatic urethra. This is why urinary retention is one symptom of prostatic hypertrophy--if the prostate is enlarged, it may close around the urethra, occluding this passage and preventing urine from exiting the bladder. The prostate gland is also extraperitoneal. Remember: the rectovesicular pouch, a fold of peritoneum that hangs between the bladder and rectum, is the lowest extent of the peritoneal cavity in males . But, the prostate is found on the posterior side of the bladder, below the point where the peritoneal membrane created this fold. So, it is an extraperitoneal organ. The lobes of the prostate are: anterior, posterior, lateral, and middle. Finally, the prostate would not be imaged using an intravenous urogram. In an intravenous urogram, a patient is given IV contrast, and radiographic images are taken as the contrast is excreted, passing through the kidneys, ureters, and bladder. Since the prostate is not part of this excretory pathway, it would not be viewed through this method.

An elderly patient is having difficulty in voiding (urinating). He complains that after voiding, he still feels as though he needs "to go" again. You suspect that this patient suffers from benign prostatic hypertrophy, which has caused enlargement of the __________ of the bladder. A) seminal colliculus B) interureteric crest C) ampulla D) trigone E) uvula

E) Uvula The uvula of the bladder is an elevation on the posterior wall of the bladder. The uvula is produced by the middle lobe of the prostate gland. If the prostate becomes enlarged (either by benign hypertrophy or malignancy) the uvula can constrict the internal urethral orifice and cause difficulty in voiding the bladder. The seminal collicus is an elevation on the posterior wall of the prostatic urethra. The interureteric crest is an elevation on the posterior wall of the bladder, between the two ureteric orifices. The ampulla of the ductus deferens is the dilated part of the ductus deferens located posterior to the bladder. It joins with the duct of the seminal vesical to form the ejaculatory duct. The trigone is a triangular area on the posterior wall of the bladder. It is delineated by the two ureteric orifices and the internal urethral orifice, which form an equilateral triangle known as the trigone.

An elderly male patient presents with dysuria and urgency. You suspect benign prostatic hypertrophy which has caused an enlargement of the: A) interureteric crest B) prostatic utricle C) seminal colliculus D) sphincter urethrae E) uvula

E) uvula The uvula of the bladder is an elevation on the posterior wall of the bladder. The uvula is caused by the middle lobe of the prostate gland. If the prostate becomes enlarged (either by benign hypertrophy or malignancy), the uvula can constrict the internal urethral orifice and cause difficulty in voiding the bladder. The interureteric crest is an elevation on the posterior wall of the bladder, between the two ureteric orifices. The seminal collicus is an elevation on the posterior wall of the prostatic urethra. At the summit of the seminal collicus, you can find the prostatic utricle, which is a small blind diverticulum in the posterior wall of the prostatic urethra. Finally, the sphincter urethrae is a muscle which encircles the urethra and compresses the urethra. None of these other structures would be enlarged in a case of benign prostatic hypertrophy.