Scrotum Flashcards
What is the scrotum?
Outpouching of the anterior abdominal wall
How does the scrotum maintain a temperature below body temperature?
By radiating heat by its thin skin and lack of fat
What three things does the scrotum contain?
Testes, epididymis, lower part of the spermatic cord
What is the function of the dartos (smooth) muscle?
Autonomic control of temperature regulation
The dartos muscle derives from what layer of the anterior abdominal wall?
Subcutaneous tissue, superficial and deep fascia
The tunica vaginalis is a derivation of what layer of the anterior abdominal wall?
Peritoneum
Which layer of the tunica vaginalis is superficial and lies internal to the internal spermatic fascia?
Parietal layer
Which layer of the tunica vaginalis is deep and is firmly adherent to the testis and epididymis?
Visceral layer
What is a hydrocele?
Accumulation of fluid in the tunica vaginalis cavity
The testis have what two types of functioning?
Gametogenic and endocrine
What are the two specific functions of the testes?
Production of spermatozoa and secretion of androgens
What is the fibrous outer covering of the testis called?
Tunica albuginea
Where is the tunica albuginea located?
Deep to the visceral layer of the tunica vaginalis which is the deepest layer of the scrotum
What are the numerous wedge shaped portions of the testis called?
Lobules
What is the fibrous compartment in the posterior part of the testis where the septa converge?
Mediastinum testis
What are the seminiferous tubules?
Functional, sperm producing portion of the testis
Each lobule contains about how many seminiferous tubules?
2-3
What is the rete testis?
An elaborate network of canals located within the mediastinum testis into which the straight tubules empty
What are the efferent ductules?
Ducts which connect the rete testis to the head of the epididymis
What is the epididymis?
A C-shaped structured attached to the superior and posterior aspect of the testis
What is the function of the epididymis?
To store sperm until they mature
What part of the epididymis is connected to the superior surface of the testis by the efferent ductules?
Head
What part of the epididymis is located along the posterior surface of the testis?
Body
What part of the epididymis ends in the ductus deferens?
Tail
Where is the first place that testicular cancer spreads?
Abdomen
Where does lymph from the testis drain?
Into the lumbar nodes
Where does lymph from the scrotum drain?
Into the superficial inguinal nodes
Where do the testes originally develop?
In the lumbar region inside the abdominal cavity
When do the testes usually descend through the inguinal canal into the scrotum?
Just before birth
What is the name of the ligament present in the fetus which connects the testis to the scrotum?
Gubernaculum testis
What is the function of the gubernaculum testis?
Contracts to pull the testis downward and through the inguinal canal during its descent
What is cryptorchidism?
The absence of one or both testes from the scrotum at birth due to lack of descent from the abdomen
The testes are undescended at birth in what percent of full term infants?
3%
The testes are undescended at birth in what percent of premature infants?
30%
What is the link between undescended testes and cancer?
Greater risk of cancer
Is cryptorchidism typically bilateral or unilateral?
Unilateral
Where are undescended testes most commonly found?
In the inguinal canal
When do most initially undescended testes finally make their descent?
In the first weeks or months after birth
What are the results of testes that never descend?
Infertility (but unimpaired androgen secretion)
What is the treatment for cryptorchidism?
Testosterone
What is the peritoneum?
Smooth membrane which lines the abdominal cavity
Which part of the peritoneum lines the abdominal walls?
Parietal peritoneum
Which part of the peritoneum covers the abdominal organs?
Visceral peritoneum
What is the peritoneal cavity?
A potential space between the parietal and visceral peritoneum
What should be the only thing found in the peritoneal cavity?
Small film of serous fluid
In which gender is the peritoneal cavity a completely closed sac?
Male
What structure in females allows communication between the peritoneal cavity and the exterior?
Uterine tubes
Infections of the vagina can spread to the peritoneal cavity via what route?
Uterine tubes
How can potency of the uterine tubes be tested?
Dye is introduced into the uterus and usually enters the uterine tubes then the peritoneal cavity. If it does not, there is an obstruction.
What are the functions of the peritoneum?
Minimize friction between organs, resist infection, fat storage
Retroperitoneal organs are covered by peritoneum only on what surface?
Anterior
What is ascites?
Accumulation of fluid in the peritoneal cavity
What are examples of retroperitoneal structures?
Aorta, inferior vena cava, kidney
What are examples of partially retroperitoneal structures?
Duodenum, pancreas
When ascites is present, there is an imbalance of what two things?
Absorption and fluid production
In a healthy person, the peritoneum has what characteristic in regards to fluid?
Highly absorbent
The peritoneal cavity is used for what two medical procedures/situations?
Rabies vaccine, kidney dialysis
What are the causes of ascites?
Malnutrition, congestive heart failure, liver failure, kidney failure, peritonitis
What is peritonitis?
Inflammation of the peritoneum, usually from infection
What are the cases of peritonitis?
Trauma, inflammatory bowl disease (ruptured appendix), vaginal infections, perforated ulcers
What usually occurs with peritonitis?
Adhesions between the parietal and visceral peritoneum
What can also cause adhesions between the layers of the peritoneum and lead to bowl obstruction?
Abdominal surgery
What is the innervation of the parietal layer of the peritoneum?
Phrenic, intercostal, subcostal, iliohypogastric, and ilioinguinal nerves
Which layer of the peritoneum is very sensitive to pain?
Parietal layer
Which layer of the peritoneum is insensitive to pain?
Visceral layer
What is the innervation of the visceral layer of the peritoneum?
Autonomic nerves which travel within the organs it invests
What is an omentum?
Broad, apron-like reflection of peritoneum
The greater omentum hangs from which part of the stomach?
Greater curvature
The greater omentum reflects posteriorly to attach to what structures?
Transverse colon and transverse mesocolon
The gastrophrenic ligament is between what structures?
Greater curvature of the stomach and diaphragm
The gastrosphenic ligament is between what structures?
Greater curvature of the stomach and spleen
The gastrocolic ligament is between what structures?
Greater curvature of the stomach and transverse colon
What is the largest part of the greater omentum?
Gastrocolic ligament
What are the three parts of the greater omentum?
Gastrophrenic, gastrosplenic, and gastrocolic ligaments
What nickname does the greater omentum have and why?
“Abdominal policeman” because it is mobile and adheres to areas of inflammation by wrapping itself around inflamed organs preventing the spread of infection
The lesser omentum is a double layer of peritoneum that extends from what structures?
Porta hepatis of the liver to the lesser curvature of the stomach and the beginning of the duodenum
What are the two parts of the lesser omentum?
Hepatogastric ligament and hepatoduodenal ligament
The hepatogastric ligament is between what structures?
Liver and the lesser curvature of the stomach
The hepatoduodenal ligament is between what structures?
Liver and the duodenum
Which segments of the small intestine are mobile and therefore most likely involved in inguinal hernia?
Jejunum and ileum
What is the general meaning of mesentery?
Any double layer of peritoneum which connects a portion of intestine to the body wall
What is the specific meaning of mesentery?
The double layer of peritoneum which connects the jejunum and ileum to the body wall (AKA mesentery proper)
What does the transverse mesocolon do?
Connects the transverse colon to the posterior body wall
What does the sigmoid mesocolon do?
Connects the sigmoid colon to the pelvic wall
What does the mess appendix do?
Connects the appendix to the mesentery of the ileum
Which ligament suspends the left colic flexure in a superior position?
Phrenicocolic ligament
What does the phrenicocolic attach?
Left colic flexure to the diaphragm, below the spleen
What is the omental bursa (lesser sac)
Irregularly shaped space which lies posterior to the liver, lesser omentum, and stomach
What is the greater sac?
Space extending from the diaphragm to the pelvic floor and across the entire breadth of the abdominal cavity
What subdivision of the greater sac is located below the diaphragm and above the liver, to the right of the falciform ligament?
Right subphrenic space (recess)
What subdivision of the greater sac is located below the diaphragm and above the liver, to the left of the falciform ligament?
Left subphrenic space (recess)
What subdivision of the greater sac is between the liver and the transverse colon?
Subhepatic space (recess)
What is the posterosuperior extension of the sub hepatic space between the liver and right kidney?
Hepatorenal recess
What subdivision of the greater sac is a longitudinal depression lateral to the ascending colon?
Right paracolic gutter
What subdivision of the greater sac is a longitudinal depression lateral to the descending colon?
Left paracolic gutter
Why are the subdivisions of the greater sac important?
They channel and compartmentalize peritoneal fluid and infectious processes
What is another name for the omental foramen?
Epiploic foramen
What is the superior boundary of the omental foramen?
Liver
What is the inferior boundary of the omental foramen?
First part of the duodenum
What is the anterior boundary of the omental foramen?
Free edge of the lesser omentum
What is the posterior boundary of the omental foramen?
Peritoneum covering the inferior vena cava
What structures pass through the porta hepatis and are surrounded by the lesser omentum?
Bile duct (to the right), hepatic artery proper (to the left), and the portal vein (behind)
