Accuracy of Bladder Scanning in the Assessment of Postvoid Residual Volume

Objective: To compare the accuracy of the 3D portable ultrasound with catheterization in the assessment of postvoid residual (PVR) urine volume among women in the urogynaecology clinic. Methods: A prospective study was performed, assessing 101 women. After the patient voided four ultrasound (US) assessments were carried out using the BladderScan BVI 3000; the patient was then catheterized. The reproducibility of the US measurements and the difference between the two methods were assessed using Bland and Altman plots. The strength of the relationship was measured by a simple Pearson correlation coefficient. Results: The results showed that 3D scanner measurements were highly reproducible and were also found to correlate significantly with catheterized volume (r = 0.79, 95% CI 0.70-0.85, P < 0.001). The mean difference between the two methods was 12.9 ml (95% CI 5.5-20.2 mL, P < 0.001). Conclusion: In determining PVR volumes, the portable ultrasound BladderScan BVI 3000 is an accurate alternative to bladder catheterization.