GI Diagnostic Procedures and Endoscopy 1 — Questions and Answers
Question 1: Which bowel preparation is most commonly used before colonoscopy in the United States?
- Sodium phosphate enema only
- Polyethylene glycol (PEG) electrolyte solution (Correct answer)
- Castor oil
- Saline laxative tablets alone
Correct answer: Polyethylene glycol (PEG) electrolyte solution
Polyethylene glycol-based solutions (e.g., GoLYTELY) are the most widely used colonoscopy prep due to safety and efficacy across patient populations.
Question 2: The Boston Bowel Preparation Scale (BBPS) scores each of the three colon segments from 0 to 3; what is the minimum acceptable total score for an adequate colonoscopy?
- 3
- 5
- 6 (Correct answer)
- 9
Correct answer: 6
A BBPS total score of ≥6 (with no individual segment score <2) is generally considered adequate preparation for colonoscopy.
Question 3: During upper endoscopy (EGD), the Z-line (squamocolumnar junction) is normally located at approximately how many centimeters from the incisors?
- 25–30 cm
- 35–40 cm (Correct answer)
- 40–50 cm
- 50–55 cm
Correct answer: 35–40 cm
The gastroesophageal junction and Z-line are typically found at 35–40 cm from the incisors in adults of average height.
Question 4: Capsule endoscopy is considered the first-line test for suspected bleeding in which GI region?
- Esophagus
- Stomach
- Small bowel (mid-GI) (Correct answer)
- Rectum
Correct answer: Small bowel (mid-GI)
Video capsule endoscopy is the first-line investigation for obscure GI bleeding or suspected small bowel pathology beyond the reach of standard endoscopes.
Question 5: Endoscopic retrograde cholangiopancreatography (ERCP) is considered first-line therapy for which condition?
- Pancreatic pseudocyst drainage
- Suspected cholangiocarcinoma biopsy only
- Common bile duct stones (choledocholithiasis) (Correct answer)
- Screening for pancreatic cancer
Correct answer: Common bile duct stones (choledocholithiasis)
ERCP with sphincterotomy and stone extraction is the standard of care for choledocholithiasis causing biliary obstruction or cholangitis.
Question 6: Which finding on colonoscopy requires removal and is considered a premalignant lesion?
- Hyperplastic polyp <5 mm in the rectum
- Tubular adenoma (Correct answer)
- Subepithelial lipoma
- Normal mucosa with prominent vessels
Correct answer: Tubular adenoma
Tubular adenomas are adenomatous polyps with dysplastic epithelium and malignant potential, requiring polypectomy.
GI Diagnostic Procedures and Endoscopy 1
Which bowel preparation is most commonly used before colonoscopy in the United States?