Abdomen — MCQs

Abdomen Indian Medical PG Practice Questions and MCQs

Question 721: A CT scan of the abdomen reveals a mass in the pancreatic uncinate process. Which of the following structures is most likely to be compressed by this mass?

A. Common bile duct
B. Portal vein
C. Splenic vein
D. Superior mesenteric vein (Correct Answer)

Explanation: ***Superior mesenteric vein*** - The **uncinate process** of the pancreas hooks around the **superior mesenteric vessels**. Therefore, a mass in this region would most directly compress the **superior mesenteric vein (SMV)** and artery (SMA). - Compression of the SMV can lead to **venous outflow obstruction** from the small intestine, potentially causing **bowel ischemia** or edema. *Common bile duct* - The **common bile duct** passes through the **head of the pancreas**, not typically the uncinate process. - Compression of the common bile duct would more commonly be associated with masses in the **head of the pancreas**, leading to **jaundice**. *Portal vein* - The **portal vein** is formed by the union of the **splenic vein** and the **superior mesenteric vein**, generally posterior to the neck of the pancreas. - While pancreatic masses can affect the portal vein, a mass specifically in the uncinate process would more directly impinge on the SMV before significantly affecting the main portal vein, which is superior and posterior to the uncinate process. *Splenic vein* - The **splenic vein** runs along the **posterior aspect of the body and tail of the pancreas**. - A mass in the uncinate process, located at the inferior margin of the head, is relatively distant from the splenic vein.

Question 722: Celiac vessel is seen at which vertebral level?

A. L2
B. T9
C. T12 (Correct Answer)
D. T10

Explanation: T12 - The celiac trunk arises from the abdominal aorta at the level of the twelfth thoracic vertebra (T12), just below the aortic hiatus of the diaphragm. - This is typically at the level of the upper border of L1 or lower border of T12. - It is the first major unpaired visceral branch and supplies the foregut organs (stomach, proximal duodenum, liver, spleen, pancreas). L2 - The renal arteries, which supply the kidneys, typically originate from the aorta at the level of the L1-L2 vertebra. - The inferior mesenteric artery (IMA) arises at approximately L3 level. - This level is significantly lower than the origin of the celiac trunk. T9 - At the level of T9, no major visceral branches arise from the aorta. - This level is above the aortic hiatus (at T12), so the aorta is still in the thoracic cavity. - The celiac trunk has not yet branched at this higher level. T10 - At T10, the aorta is still in the thoracic cavity, passing through the posterior mediastinum. - The aortic hiatus of the diaphragm is at T12, not T10. - No major unpaired visceral branches originate at this level.

Question 723: The following statements concerning the abdominal part of the sympathetic trunk are not true EXCEPT:

A. All the ganglia receive white rami communicantes
B. It enters the abdomen behind the lateral arcuate ligament
C. The trunk passes in 6 segmentally arranged ganglia
D. Gray rami communicantes are given off to the lumbar spinal nerves (Correct Answer)

Explanation: ***Gray rami communicantes are given off to the lumbar spinal nerves*** - All **sympathetic ganglia**, including those in the abdominal sympathetic trunk, give off **gray rami communicantes** to their corresponding spinal nerves. - These gray rami carry **postganglionic sympathetic fibers** to the spinal nerves for distribution to peripheral structures such as blood vessels, sweat glands, and piloerector muscles. *All the ganglia receive white rami communicantes* - **White rami communicantes** carry **preganglionic sympathetic fibers** from the spinal cord to the sympathetic trunk. - These are typically only found at the **thoracolumbar levels** (T1-L2), corresponding to the origin of the sympathetic outflow, meaning not all abdominal ganglia receive them. *It enters the abdomen behind the lateral arcuate ligament* - The sympathetic trunk enters the abdomen by passing **behind the medial arcuate ligament** (or crus of the diaphragm), not the lateral arcuate ligament. - The **lateral arcuate ligament** typically bridges over the quadratus lumborum muscle. *The trunk passes in 6 segmentally arranged ganglia* - The abdominal part of the sympathetic trunk usually consists of **4 lumbar ganglia**, rather than 6. - These ganglia are segmentally arranged in relation to the lumbar vertebrae.

Question 724: Ureteric constriction is seen at all the following positions, except

A. Crossing of iliac artery
B. Ureterovesical junction
C. Ureteropelvic junction
D. Ischial spine (Correct Answer)

Explanation: ***Ischial spine*** - The ureter does **not** experience a physiological constriction at the level of the **ischial spine**. - While the ureter is in proximity to the ischial spine as it descends into the pelvis, this anatomical location is **not a recognized site of physiological narrowing**. *Crossing of iliac artery* - The ureter is physiologically constricted where it crosses anterior to the **iliac artery** (common or external), which is a common site for **kidney stone impaction**. - This is an important narrowing because the ureter changes direction and is compressed by the vessel. *Ureterovesical junction* - The **ureterovesical junction (UVJ)**, where the ureter enters the bladder, is the **narrowest point** of the entire ureter. - This constriction helps prevent **vesicoureteral reflux** and is a frequent site for stone impaction. *Ureteropelvic junction* - The **ureteropelvic junction (UPJ)**, where the renal pelvis narrows to become the ureter, is another significant physiological constriction point. - **Ureteropelvic junction obstruction** can occur at this site, leading to hydronephrosis.

Question 725: Free nerve endings carrying nociceptive fibers are seen in:

A. Spleen
B. Liver
C. Mesentery (Correct Answer)
D. Intestine

Explanation: ***Mesentery*** - The mesentery is **richly innervated with free nerve endings** that carry nociceptive (pain) fibers, making it highly sensitive to painful stimuli [1]. - These nerve endings respond to **stretch, traction, ischemia, and inflammation**, transmitting visceral pain signals via **sympathetic pathways** (T5-L2) [2]. - The mesentery's abundant nociceptive innervation is why **peritoneal irritation** and **mesenteric traction** during surgery cause significant pain [4]. - Free nerve endings in the mesentery are a key component of **visceral pain perception** in abdominal pathologies [1]. *Intestine* - The intestinal **mucosa and muscle layers** have relatively **few pain receptors** and are insensitive to cutting, burning, or crushing [1]. - Pain from the intestine primarily arises from the **serosal surface** (peritoneal covering) and associated mesentery, not from the intestinal wall itself [4]. - Intestinal pain is typically due to **distension, ischemia, or inflammation** affecting the serosa or mesentery [2]. *Liver* - The liver parenchyma is **devoid of pain receptors** - it has no free nerve endings for nociception [3]. - Hepatic pain originates only from **stretching of Glisson's capsule** (the fibrous covering), not from the liver tissue itself [3]. - This capsular pain may be referred to the right upper quadrant or shoulder via phrenic nerve (C3-C5) [4]. *Spleen* - The spleen has **sparse nociceptive innervation** and is relatively insensitive to pain. - Splenic pain, when present, typically results from **capsular distension or rupture**, not from the splenic parenchyma itself. - Pain from splenic pathology is often referred to the left shoulder (Kehr's sign) [4].

Question 726: The primary arterial supply to the stomach is from

A. Gastroduodenal artery
B. Inferior pancreaticoduodenal artery
C. Splenic artery
D. Celiac trunk (Correct Answer)

Explanation: ***Celiac trunk*** - The **celiac trunk** is the main and **primary arterial supply** to the stomach, liver, spleen, and pancreas, branching into the left gastric, splenic, and common hepatic arteries [1]. - The **left gastric artery** directly supplies the lesser curvature of the stomach, while branches from the **splenic** and **common hepatic arteries** supply the greater curvature and pylorus. *Gastroduodenal artery* - The **gastroduodenal artery** is a branch of the **common hepatic artery**, primarily supplying the **duodenum** and head of the **pancreas**. - It gives rise to the **right gastroepiploic artery**, which supplies the greater curvature of the stomach, but it's not the primary supply to the entire stomach. *Inferior pancreaticoduodenal artery* - The **inferior pancreaticoduodenal artery** typically arises from the **superior mesenteric artery**, supplying the **head of the pancreas** and the inferior part of the **duodenum**. - It does not directly contribute significantly to the arterial supply of the stomach. *Splenic artery* - The **splenic artery** is a branch of the **celiac trunk** that primarily supplies the **spleen**. - It gives off the **short gastric arteries** and the **left gastroepiploic artery**, which supply parts of the greater curvature and fundus of the stomach, but it's not the primary source for the entire organ.

Question 727: The ovarian artery originates directly from which vessel?

A. Renal artery
B. Inferior mesenteric
C. Common iliac
D. Abdominal aorta (Correct Answer)

Explanation: ***Abdominal aorta*** - The **ovarian arteries**, also known as **gonadal arteries** in females, typically arise directly from the **anterolateral aspect of the abdominal aorta**, just inferior to the renal arteries. - This direct origin from the main arterial trunk is crucial for supplying blood to the **ovaries**, **fallopian tubes**, and surrounding **ligaments**. *Renal artery* - The **renal arteries** supply blood to the kidneys and originate superior to the ovarian arteries from the **abdominal aorta**. - While anatomically close, the ovarian artery does not branch off the renal artery. *Inferior mesenteric* - The **inferior mesenteric artery** supplies blood to the distal large intestine and originates from the **abdominal aorta** inferior to the ovarian arteries. - Its branching point is distinct and supplies different organs. *Common iliac* - The **common iliac arteries** are terminal branches of the **abdominal aorta** that divide into external and internal iliac arteries, supplying the lower limbs and pelvic organs, respectively. [1] - The ovarian arteries originate much higher up the aorta and do not branch from the common iliac arteries.

Question 728: The epiploic foramen connects which two anatomical spaces?

A. Right pleural cavity
B. Anterior mediastinum
C. Greater and lesser sac (Correct Answer)
D. Retroperitoneal space

Explanation: ***Greater and lesser sac*** - The **epiploic foramen** (or foramen of Winslow) is the natural opening that connects the **greater peritoneal cavity** (greater sac) with the **lesser peritoneal cavity** (lesser sac or omental bursa). - This connection allows for the passage of peritoneal fluid between these two main compartments of the abdomen. *Right pleural cavity* - The **right pleural cavity** is located in the thorax and contains the right lung; it is entirely separate from the abdominal peritoneal cavities. [1] - The diaphragm separates the abdominal and thoracic cavities, preventing direct connection through a foramen like the epiploic foramen. [1] *Anterior mediastinum* - The **anterior mediastinum** is a compartment within the thorax, between the sternum and the pericardium, housing structures like the thymus and lymph nodes. [1] - It is a thoracic, not an abdominal, space and has no anatomical connection to the peritoneal cavity via the epiploic foramen. *Retroperitoneal space* - The **retroperitoneal space** lies behind the peritoneum in the abdominal cavity, containing organs like the kidneys, pancreas, and aorta. - While adjacent to the peritoneal cavity, it is distinct from it and not directly connected to the greater or lesser sac via the epiploic foramen.

Question 729: Which of the following organs is directly supplied by a branch of the celiac trunk?

A. None of the options
B. Spleen (via splenic artery) (Correct Answer)
C. Pancreas (via gastroduodenal artery)
D. Liver (via gastroduodenal artery)

Explanation: ***Spleen (via splenic artery)*** - The **celiac trunk** has three direct branches: **left gastric artery**, **common hepatic artery**, and **splenic artery** - The **splenic artery** is a direct branch of the celiac trunk that supplies the spleen, along with portions of the pancreas and stomach via its branches [1] - This is the correct answer as it accurately pairs an organ with its direct celiac trunk branch *Pancreas (via gastroduodenal artery)* - While the pancreas does receive blood supply from celiac trunk branches, the **gastroduodenal artery** is NOT a direct branch - The gastroduodenal artery is a **secondary branch** arising from the common hepatic artery - The pancreas is actually **directly supplied** by branches of the splenic artery and superior pancreaticoduodenal artery (from gastroduodenal) [1] - This option incorrectly attributes the supply to an indirect branch *Liver (via gastroduodenal artery)* - The liver is primarily supplied by the **hepatic artery proper**, which comes from the common hepatic artery (a direct celiac trunk branch) - The **gastroduodenal artery** does NOT supply the liver; it supplies the pylorus, duodenum, and head of pancreas - This option incorrectly pairs the liver with the wrong artery *None of the options* - Incorrect because the spleen is correctly identified as being directly supplied by the splenic artery, a direct branch of the celiac trunk

Question 730: During a laparoscopic examination, a surgeon notes a pulsating structure posterior to the neck of the pancreas. Which vessel is likely being observed?

A. Superior mesenteric artery (Correct Answer)
B. Superior mesenteric vein
C. Portal vein
D. Splenic artery

Explanation: Superior mesenteric artery - The superior mesenteric artery (SMA) originates from the aorta and passes posterior to the neck of the pancreas, making it a pulsating structure in this anatomical location. - Its position is crucial in conditions like SMA syndrome, where the duodenum is compressed between the SMA and the aorta. Superior mesenteric vein - The superior mesenteric vein (SMV) also passes posterior to the neck of the pancreas, but it is a vein, not an artery, and therefore does not typically exhibit a pulsating characteristic. - The SMV is formed from tributaries draining the small intestine and part of the large intestine, eventually joining the splenic vein to form the portal vein. Portal vein - The portal vein is formed posterior to the neck of the pancreas by the confluence of the superior mesenteric vein and the splenic vein. - While it is located in the vicinity, its formation is posterior to the neck, and as a vein, it generally does not pulsate. Splenic artery - The splenic artery runs along the superior border of the pancreas, anterior to the vertebral column, before reaching the spleen. - It is not typically found posterior to the neck of the pancreas in a position to be observed as described.

Practice by Chapter

Anterior Abdominal Wall

Practice Questions

Peritoneum and Peritoneal Cavity

Practice Questions

Stomach and Intestines

Practice Questions

Liver, Gallbladder and Biliary Tract

Practice Questions

Pancreas and Spleen

Practice Questions

Kidneys and Suprarenal Glands

Practice Questions

Abdominal Vasculature

Practice Questions

Posterior Abdominal Wall

Practice Questions

Innervation of Abdominal Viscera

Practice Questions

Applied Anatomy and Clinical Correlations

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free

Abdomen — MCQs

Abdomen — MCQs

On this page

Practice by Chapter

Want unlimited practice?