Colorectal Surgery Practice Questions

Q: What is the most common cause of lower gastrointestinal bleeding?

Hemorrhoids. **Explanation:** The most common cause of lower gastrointestinal (GI) bleeding overall is **Hemorrhoids**. While often presenting as minor, painless, bright red rectal bleeding (hematochezia) during or after defecation, their high prevalence in the general population makes them the leading cause of lower GI blood loss. **Why the other options are incorrect:** * **Diverticulosis:** This is the most common cause of **massive, painless** lower GI bleeding in the elderly. While it causes more significant volume loss per episode than hemorrhoids, it is less frequent in the general population. * **Crohn’s Disease:** Inflammatory Bowel Disease (IBD) can cause bloody diarrhea and mucus, but it is a much less common cause of bleeding compared to anorectal pathologies. * **Colorectal Cancer:** While a critical diagnosis to rule out in any patient presenting with hematochezia or iron-deficiency anemia, it is statistically less common than benign causes like hemorrhoids or diverticula. **NEET-PG High-Yield Pearls:** 1. **Most common cause of LGIB:** Hemorrhoids. 2. **Most common cause of *massive* LGIB:** Diverticulosis (specifically right-sided diverticula are more prone to bleed). 3. **Most common cause of LGIB in children:** Meckel’s Diverticulum. 4. **Most common cause of occult GI bleeding:** Iron deficiency anemia secondary to Colorectal Cancer (until proven otherwise). 5. **Angiodysplasia:** The second most common cause of massive LGIB in the elderly; often associated with Aortic Stenosis (**Heyde’s Syndrome**).

Q: Which of the following are types of setons used in fistula in ano surgery?

Cutting seton and draining seton. In the surgical management of fistula-in-ano, a **seton** is a foreign material (such as silk, polypropylene, or vessel loops) passed through the fistula tract. The choice of seton depends on whether the goal is to promote drainage or to gradually divide the sphincter muscle. **1. Why Option C is Correct:** * **Cutting Seton:** This is used to treat "high" or complex fistulae. It is tied tightly and tightened periodically in the clinic. It works by slowly cutting through the sphincter muscle while simultaneously inducing fibrosis behind it. This prevents the muscle ends from snapping apart, thereby maintaining continence while the tract heals. * **Draining (Non-cutting) Seton:** This is tied loosely around the tract. Its primary purpose is to keep the tract open to prevent the formation of recurrent abscesses and to allow the tract to epithelialize and mature before a definitive secondary procedure (like a LIFT or advancement flap). **2. Why Other Options are Incorrect:** * **Dissecting/Fibrosing Seton:** These are not standard surgical classifications. While setons do cause fibrosis, "fibrosing seton" is not a formal term used in surgical literature. * **Dissolving Seton:** Setons are intended to stay in place for weeks or months; therefore, they are made of non-absorbable materials. A dissolving material would fail to provide the necessary long-term tension or drainage. **High-Yield Clinical Pearls for NEET-PG:** * **Goodsall’s Law:** Predicts the trajectory of the fistula tract based on the location of the external opening relative to the transverse anal line. * **Park’s Classification:** Categorizes fistulae into Intersphincteric (most common), Transsphincteric, Suprasphincteric, and Extrasphincteric. * **Hippocrates** was the first to describe the use of a seton (using horsehair). * **Kshara Sutra:** A traditional Indian medicated seton used for gradual chemical cauterization and healing of the tract.

Q: What is the most common site of a chronic fissure in ano?

Posterior. **Explanation:** An anal fissure is a linear tear in the distal anal mucosa, extending from the dentate line to the anal verge. **Why Posterior is Correct:** The **posterior midline** is the most common site for chronic anal fissures, occurring here in over **90% of cases**. The primary pathophysiological reason is the **lack of muscular support** and **poor blood supply** (relative ischemia) at the posterior commissure. The elliptical arrangement of the external anal sphincter fibers provides less support posteriorly compared to the lateral sides. Additionally, during defecation, the acute angle of the anorectal junction causes the greatest mechanical strain to be exerted on the posterior anal canal. **Why Other Options are Incorrect:** * **Anterior:** This is the second most common site, seen in about 10% of women and 1% of men. Anterior fissures are often associated with pelvic floor weakness or trauma during childbirth. * **Lateral/Anterolateral:** Fissures in these locations are highly uncommon. If a fissure is found in a lateral position, a clinician must suspect underlying systemic conditions such as **Crohn’s disease**, tuberculosis, HIV/AIDS, or anal malignancy. **High-Yield Clinical Pearls for NEET-PG:** * **Sentinel Pile:** A chronic fissure is characterized by a triad: the fissure itself, hypertrophied anal papillae (proximal), and a **sentinel skin tag** (distal). * **Management:** The gold standard surgical treatment for chronic fissure in ano is **Lateral Internal Sphincterotomy (LIS)**. * **Pathophysiology:** The "vicious cycle" of a fissure involves pain leading to internal sphincter spasm, which causes ischemia, preventing the tear from healing.

Q: What is the treatment of choice for a 70-year-old male patient presenting with peritonitis secondary to ruptured diverticulitis?

Hamann's procedure. **Explanation:** The clinical presentation of peritonitis secondary to ruptured diverticulitis (Hinchey Stage III or IV) in an elderly patient is a surgical emergency. The treatment of choice is **Hartmann’s Procedure** (noted as Hamann’s in the options). **1. Why Hartmann’s Procedure is Correct:** In the setting of fecal or purulent peritonitis, the bowel wall is often edematous, and the peritoneal cavity is heavily contaminated. Performing a primary anastomosis under these conditions carries a high risk of **anastomotic leak**, which can be fatal in a 70-year-old. Hartmann’s procedure involves resection of the diseased sigmoid colon, closure of the rectal stump, and creation of an end-descending colostomy. This "staged" approach prioritizes patient safety by removing the source of sepsis without the risk of a breakdown at the suture line. **2. Why Other Options are Incorrect:** * **Conservative Management:** This is appropriate for uncomplicated diverticulitis (Hinchey I). Peritonitis indicates a perforation, which is a surgical emergency. * **Primary Resection and Anastomosis:** While increasingly used in stable, younger patients with Hinchey II/III disease, it is generally avoided in elderly patients with frank peritonitis due to the high risk of leak and mortality. * **Whipple Procedure:** This is a pancreaticoduodenectomy used for periampullary or pancreatic head cancers, not for colonic pathology. **Clinical Pearls for NEET-PG:** * **Hinchey Classification:** Stage I (Pericolic abscess), Stage II (Pelvic abscess), Stage III (Purulent peritonitis), Stage IV (Fecal peritonitis). * **Gold Standard:** Hartmann’s remains the classic "gold standard" for Hinchey III and IV. * **Laparoscopic Lavage:** A controversial alternative for Hinchey III, but not yet the standard for elderly patients with systemic sepsis.

Q: Which of the following is a known complication of a stoma (e.g., colostomy)?

All of the above. ### Explanation Stoma complications are a high-yield topic in surgical exams, categorized into **early** (within 30 days) and **late** (after 30 days) complications. The correct answer is **D (All of the above)** because prolapse, stenosis, and retraction are well-documented sequelae of stoma formation. * **Prolapse (Option A):** This is a late complication where the bowel protrudes through the stoma site. It is more common in loop colostomies than end stomas. It occurs due to an oversized fascial opening or increased intra-abdominal pressure. * **Stenosis (Option B):** This refers to the narrowing of the stoma outlet. It often results from chronic ischemia, peristomal skin infections, or excessive scarring during healing. It can lead to obstructive symptoms. * **Retraction (Option C):** This occurs when the stoma sinks below the skin level. It is often caused by excessive tension on the bowel limb, poor mobilization of the mesentery, or weight gain (increased subcutaneous fat). It leads to poor appliance fitting and skin excoriation. **Clinical Pearls for NEET-PG:** * **Most common early complication:** Skin excoriation/dermatitis (due to leakage). * **Most common late complication:** Parastomal hernia. * **Necrosis:** Usually occurs within the first 24 hours due to compromised blood supply; if it extends below the fascial level, immediate re-operation is required. * **Ideal Stoma Site:** Should be placed through the **rectus abdominis muscle** to reduce the risk of herniation and away from bony prominences or skin folds.

Q: Carcinoma of the right colon commonly presents as:

Fungating lesion. **Explanation:** Carcinoma of the colon exhibits distinct morphological patterns depending on its anatomical location. This difference is primarily due to the embryological origin and the diameter of the bowel lumen. **1. Why "Fungating lesion" is correct:** The **right colon** (caecum and ascending colon) has a large diameter and thin, distensible walls. Additionally, the fecal matter here is liquid. Because there is ample space, tumors tend to grow as large, **exophytic, cauliflower-like, or fungating masses** that protrude into the lumen. These lesions often bleed chronically, leading to iron deficiency anemia, but rarely cause early obstruction. **2. Why the other options are incorrect:** * **Stenosing/Infiltrating lesions:** These are characteristic of the **left colon** (descending and sigmoid colon). The left colon has a narrower lumen and thicker walls. Tumors here tend to grow circumferentially (annular growth), leading to the classic "napkin-ring" appearance and early intestinal obstruction. * **Ulcerating lesion:** While any colorectal cancer can ulcerate and bleed, it is not the primary morphological description used to differentiate right-sided from left-sided growths in standard surgical pathology. **Clinical Pearls for NEET-PG:** * **Right-sided growth:** Presents with **Anemia** (occult blood loss), palpable mass in the right iliac fossa, and weight loss. * **Left-sided growth:** Presents with **altered bowel habits** (constipation/diarrhea) and features of intestinal obstruction. * **Most common site:** Historically the rectum, but there is a shifting trend toward the proximal colon (Right-sided shift). * **Investigation of choice:** Colonoscopy with biopsy. * **Tumor Marker:** CEA (primarily used for monitoring recurrence, not screening).

Q: A sentinel pile indicates:

Anal fissure. **Explanation:** A **sentinel pile** (also known as a skin tag) is a characteristic clinical feature of a **chronic anal fissure**. It is a hypertrophied skin tag located at the distal end of the fissure. **Why Anal Fissure is Correct:** An anal fissure is a longitudinal tear in the anoderm, most commonly located in the posterior midline. In the chronic stage (usually >6 weeks), constant irritation and low-grade inflammation lead to secondary changes: 1. **Sentinel Pile:** Edematous skin tag at the lower end. 2. **Hypertrophied Anal Papilla:** Located at the upper end (proximal) of the fissure. 3. **Exposed Sphincter Fibers:** The circular fibers of the internal anal sphincter become visible at the base of the ulcer. **Why Other Options are Incorrect:** * **Carcinoma of the rectum:** Typically presents with altered bowel habits, tenesmus, and bleeding per rectum; it does not produce a sentinel tag. * **Internal hemorrhoids:** These are vascular cushions that prolapse. While they may cause bleeding, they are usually painless (unless thrombosed) and do not feature a sentinel pile. * **Perianal fistula:** Characterized by an external opening on the perineal skin discharging pus or flatus, rather than a solid skin tag at the anal verge. **High-Yield Clinical Pearls for NEET-PG:** * **Location:** 90% of fissures are **posterior midline**. If a fissure is lateral, suspect systemic conditions like Crohn’s disease, TB, or HIV. * **Pathophysiology:** Associated with internal anal sphincter hypertonia and ischemia. * **Management:** The "Gold Standard" surgical treatment is **Lateral Internal Sphincterotomy (LIS)**. First-line medical management includes sitz baths, high-fiber diet, and topical nitrates (Glyceryl Trinitrate) or Calcium Channel Blockers (Diltiazem).

Question 1

What is the most common cause of lower gastrointestinal bleeding?

Accepted Answer

Hemorrhoids

Answer

Diverticulosis

Answer

Crohn's Disease

Answer

Colorectal cancer

Question 2

Which of the following are types of setons used in fistula in ano surgery?

Accepted Answer

Cutting seton and draining seton

Answer

Dissecting seton and draining seton

Answer

Cutting seton and dissolving seton

Answer

Fibrosing seton and dissecting seton

Question 3

What is the most common site of a chronic fissure in ano?

Accepted Answer

Posterior

Answer

Answer

Anterolateral

Answer

Lateral

Question 4

A 40-year-old male with descending colon cancer presents with acute intestinal obstruction. What is the emergency treatment of choice?

Accepted Answer

Hartman's procedure

Answer

Ileostomy

Answer

Left hemicolectomy

Answer

Total colectomy

Question 5

What is the treatment of choice for a 70-year-old male patient presenting with peritonitis secondary to ruptured diverticulitis?

Accepted Answer

Hamann's procedure

Answer

Conservative management

Answer

Primary resection and anastomosis

Answer

Whipple procedure

Question 6

A 70-year-old male presents with a history of lower gastrointestinal bleeding for the last six months. Sigmoidoscopic examination reveals a 4 cm mass located 3.5 cm above the anal verge. What is the treatment of choice?

Accepted Answer

Abdominoperineal resection

Answer

Colostomy

Answer

Anterior resection

Answer

Defunctioning anastomosis

Question 7

Which of the following is a known complication of a stoma (e.g., colostomy)?

Accepted Answer

All of the above

Answer

Prolapse

Answer

Stenosis

Answer

Retraction

Question 8

Carcinoma of the right colon commonly presents as:

Accepted Answer

Fungating lesion

Answer

Ulcerating lesion

Answer

Stenosing lesion

Answer

Infiltrating lesion

Question 9

A sentinel pile indicates:

Accepted Answer

Anal fissure

Answer

Carcinoma of the rectum

Answer

Internal hemorrhoids

Answer

Perianal fistula

Question 10

What is the recommended margin of clearance for anal carcinoma?

Accepted Answer

2 cm

Answer

3 cm

Answer

4 cm

Answer

5 cm

Colorectal Surgery — MCQs

Colorectal Surgery — MCQs

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