Urodynamic evaluation evaluates which of the following?

• A. Flow rate
• B. All of the above
• C. Sphincter function
• D. Bladder sensation thresholds

Answer: (B)

Urodynamic evaluation is a comprehensive study of how the bladder stores urine and how urine is expelled, using multiple measurements during filling and voiding. Flow rate is measured to see how freely urine exits, while the pressure–flow part compares detrusor pressure with actual flow to identify obstruction or weak detrusor function. Bladder sensation thresholds are recorded during filling to assess capacity and how the bladder responds to filling. Sphincter function is evaluated to determine whether the outlet opens and closes in proper coordination with detrusor activity, often with monitoring of sphincter activity or pressure. Because a full urodynamic study incorporates all these aspects, it evaluates flow, sphincter function, and bladder sensation thresholds—i.e., all of the above.