Retroperitoneum

Question 1

Prosected Urinary System

Answer 1

Question 2

Differences between Right and Left Adrenal blood supply

Answer 2

Everything is paired, the only difference is that the left adrenal vein drains into the left renal vein while the right adrenal vein drains into the inferior vena cava directly.

Question 3

Replaced artery

Answer 3

The most common anatomical variant is absent and this artery is present instead

Question 4

Why do patients with small bowel obstruction or appendicitis often report periumbilical pain?

Answer 4

The T10 and T11 spinal nerves form the lesser sphlanchic nerve, and the dermatomes of the periumbilican region correspond to these origins.

Question 5

Inflammation of the distal colon is sensed as. . .

Answer 5

Left lower abdominal to pelvic pain (left inguinal pain)

Question 6

The Retroperitoneum was developed. . .

Answer 6

outside of the abdominal cavity but was brought in during development.

Question 7

Two muscles that make up the dorsal face of the abdominal wall

Answer 7

Psoas Major Muscle

Quadratus lumborum Muscle

These lie deep to the superficial muscles of the back.

Question 8

Close-up of ganglia on upper abdominal aorta

Answer 8

Question 9

Major branches of the portal vein

Answer 9

The superior mesenteric vein

The Left gastric vein

The splenic vein

The inferior mesenteric vein

Question 10

The abdominal aorta starts at ____ and ends at _____.

Answer 10

The abdominal aorta starts at the aortic hiatus and ends at the aortic bifurcation.

Question 11

Segments of the urethra

Answer 11

Question 12

“Short” gastric arteries

Answer 12

Short arteries that run between the stomach and spleen.

Question 13

Paired (non-gut) abdominal aortic arteries

Answer 13

Question 14

While nerve plexuses on the aorta are made up of ____, the ganglia consist exclusively of ____.

Answer 14

While nerve plexuses on the aorta are made up of sympathetic and parasympathetic nerve fibers, the ganglia consist exclusively of sympathetic postganglionic neurons.

Question 15

Marginal artery of Drummond

Answer 15

Large anastomosis that runs along the mesenteric side of the colon. All colic arteries merge here, including those from both the superior and inferior mesenteric arteries

Question 16

Porto-systemic connections

Answer 16

Increased blood pressure in the portal vein due to liver disease (aka portal hypertension) can lead to venous blood diversion to the superior and inferior vena cava and their tributaries directly, circumventing the liver.

Question 17

Branches of renal artery within the kidney

Answer 17

Question 18

Sympathetic ganglia of the abdominal cavity rest on. . .

Answer 18

The root of the enteric arteries

Question 19

The aortic bifurcation gives rise to. . .

Answer 19

A R and L common iliac artery which then each give rise to internal and external iliac arteries.

Question 20

The inferior mesenteric vein may drain into ___ or ___.

Answer 20

The inferior mesenteric vein may drain into the superior mesenteric directly or via the splenic vein.

Question 21

Superior mesenteric artery branches

Answer 21

Question 22

Greater sphlanchic nerve

Answer 22

Contains nerves from T5-T9. Piggybacks on the Celiac artery.

Question 23

Spinal nerves of the posterior retroperitoneum

Answer 23

Question 24

List of porto-systemic connections

Answer 24

Paraumbilical veins (yes, the same ones from fetal circulation. With enough pressure they may reopen. Directly connects the portal vein and vena cava)

Esophageal veins (connected via the left gastric vein to portal circulation and via the esophageal plexus and azygos vein to systemic circulation)

Superior rectal vein (remember how the middle and inferior rectal arteries were a separate branch of the abdominal aorta? This is a consequence of the superior rectal vein connecting to the rectal vein plexus, which drains into systemic circulation. Alternatively it drains to portal circulation via the inferior mesenteric vein)

Question 25

The ureteres always hug ___ and always pass posterior to \_\_\_.

Answer 25

The ureteres always hug **the posterior body wall** and always pass posterior to **sex organs**. The one exception to the latter is where the ureter runs anterior to the vaginal wall just before joining the bladder.

Question 26

Branches of the inferior mesenteric artery

Answer 26

Question 27

Uretoro-vesicular junction

Answer 27

Junction where the ureters enter the bladder

Question 28

Segments of the bladder (shown in female)

Answer 28

Question 29

Unlike the vascular supply for many abdominal organs, there is no ___ within the kidney.

Answer 29

Unlike the vascular supply for many abdominal organs, there is no **anastomosis** within the kidney. This means that segments of the kidney are at greater risk for infarction, but also means that surgeons may excise one lobe of the kidney without putting the other lobes at risk.

Question 30

Autonomic ganglia on the abdominal aorta

Answer 30

Question 31

Cisterna Chyli

Answer 31

Holding tank for lymphatic fluid drained from the lower limbs and abdominal cavity. Located retroperitoneally. Connects to thoracic duct.

Question 32

\_\_\_ through ___ spinal sympathetic nerves innervate the thoracic region

Answer 32

**T1** through **T4** spinal sympathetic nerves innervate the thoracic region. **This is why angina corresponds to the nipple line and above, these are the corresponding dermatomes.**

Question 33

Renal fascia

Answer 33

**Surrounds the kidneys** and **blood vessels** of the retroperitoneum. **Fat within** the renal fascia is called **perirenal** fat while **fat just outside** the renal fascia is called **pararenal** fat.

Question 34

Rectal blood supply from internal iliac artery

Answer 34

The **middle rectal artery** and **inferior rectal artery** are both branches of the internal iliac artery, **not** the inferior mesenteric artery.

Question 35

Right Adrenal blood supply

Answer 35

Three arterial supplies: * **Right inferior adrenal artery** from the **right renal artery** * **Right middle adrenal artery** from the **aorta** * **Right adrenal branches** from the **right inferior phrenic artery** One venous return: * **Right adrenal vein** which drains into **inferior vena cava**

Question 36

Right kidney interior

Answer 36

Question 37

Arterial supplies of the pancreas

Answer 37

Gastroduodenal artery (towards the head) Splenic artery (along the superior side as it transits to the spleen)

Question 38

Branches of the celiac artery

Answer 38

Left gastric artery Splenic artery Common hepatic artery

Question 39

Blood supply to gut

Answer 39

Question 40

Major veins (like the mesenteric veins) are usually. . .

Answer 40

valveless! Unlike small veins or veins of the extremities. This allows vein anastomosis.

Question 41

Common hepartic artery anatomical variants

Answer 41

The **left replaced hepatic artery** branches off the **left gastric artery,** instead of the typical left hepatic artery branching off of the proper hepatic artery. The **right replaced hepatic artery** branches off of the **superior mesenteric artery**, instead of the typical right hepatic artery branchinf off of the proper hepatic artery.

Question 42

Arcuate ligaments

Answer 42

1: median arcuate ligament 2: medial arcuate ligament 3: lateral arcuate ligament

Question 43

Accessory artery

Answer 43

The most common anatomical variant is present **in addition to** this other anatomical variant.

Question 44

Right kidney exterior

Answer 44