Urology>>>>>Benign Prostatic Hyperplasia (BPH) and Lower Urinary Tract Symptoms (LUTS)
Question 11#

An 82-year-old man with mixed storage and voiding LUTS is referred for urodynamics. His Q_max is 15 mL/s and a pdet at Q_max of 85 cm H20. What is the bladder outlet obstruction index for this man?

A. 45
B. 50
C. 55
D. 70
E. 103

Correct Answer is C

Comment:

Answer C

When performing urodynamics the diagnosis of bladder outlet obstruction is made by plotting the maximum flow rate (Q_max) against detrusor pressure at Q_max (pdetQ_max) into the International Continence Society Nomogram. The degree of obstruction is calculated using the Bladder Outlet Obstruction Index (BOOI) equation: BOOI = pdet@Q_max – 2Q_max.

If the BOOI is >40 then the patient is obstructed, if it is below 20 then the patient is unlikely to be obstructed and between 20–40 the findings are equivocal.