Measurement of postvoid residual urine with portable transabdominal bladder ultrasound scanner and urethral catheterization

The study was a clinical series of 95 ambulatory women with urinary inconti nence. After voiding, each subject was scanned with a BladderScan BVI 2500, then catheterized for postvoid residual (PVR) and then scanned again. The mean PVR obtained by ultrasound was 49 mi. significantly larger than the me an PVR of 32 mi obtained by catheterization. Correlation analysis showed th at the difference was not related to age. weight, body mass index, parity, pelvic prolapse or prior incontinence surgery, but was associated with prio r hysterectomy and uterine prolapse. Regression analysis revealed that the difference was independently related to prior hysterectomy only. Postcathet erization ultrasound detected a mean of 22 mi. suggesting that the differen ce between the PVR values may be due to residual urine not removed by cathe terization. Finally, ultrasound had a sensitivity; of 66.7% and a specifici ty of 96.5% in detecting PVR greater than or equal to 100 mi. Portable ultr asound scanners are quick, easy to use, reasonably sensitive, and very spec ific for determining elevated PVR.