The accuracy of portable ultrasound scanning in the measurement of residual urine volume.
The accuracy of 2 successive models of a portable (2.5 kg.) ultrasound unit in determining residual urine volumes in 100 patients was assessed. Ultrasound measurements were compared to post-scan bladder volumes obtained by catheterization and fluoroscopic screening in the same patients. The first ultrasound unit (group 1, 50 patients) showed correlation with residual volumes of 0.86 (R2 = 0.73) and a mean difference from the true residual volume of 41 ml. (95% confidence interval 26 to 55 ml.). The second ultrasound unit (group 2, 50 patients) showed correlation with residual volumes of 0.97 (R2 = 0.94) and a mean difference from the true residual volume of 24 ml. (95% confidence interval 17 to 31 ml.). The differences in volumes were significantly lower with scanner 2 (t = 2.02, p = 0.047). The mean difference between catheter volume estimate and true bladder volume was 25 ml. (95% confidence interval 16 to 34 ml.). The accuracy of the BladderScan BVI 2500+ scanner is as good as catheter estimations of true residual volume and is sufficient to recommend its use as an alternative to catheterization for the determination of residual urine volume.
Department of Urology, Prince Henry Hospital, Sydney, Australia.
G M
GM
Coombes
R J
RJ
Millard
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014463:Ultrasonography / Q000295:instrumentation; D001745:Urinary Bladder Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D014556:Urine