Question

During TURP, the surgeon takes care to dissect above the verumontanum so as to prevent injury to which structure?

• A. External urethral sphincter
• B. Urethral crest
• C. Prostatic utricle
• D. Trigone of bladder

Hint:

The continence-preserving sphincter sits just distal to the verumontanum, so resection stays proximal to it.

Answer 1

The Correct Option is A

Step 1: Recall the anatomy of the verumontanum (colliculus seminalis). It is a prominence on the posterior wall of the prostatic urethra and is a critical surgical landmark during transurethral resection of the prostate (TURP).
Step 2: Understand the relationship of the external urethral sphincter (rhabdosphincter). The external (distal) urethral sphincter lies just distal to the verumontanum, in the membranous urethra. It is responsible for maintaining urinary continence.
Step 3: Apply this to the resection. During TURP the surgeon must stop resecting at the verumontanum and keep the resection proximal (above) to it; resecting distal to the verumontanum risks damaging the external sphincter and causing urinary incontinence.
Step 4: Therefore, dissecting above (proximal to) the verumontanum protects the external urethral sphincter. The urethral crest, prostatic utricle and bladder trigone are not the structures protected by this manoeuvre.
Answer: A (External urethral sphincter).