The Accuracy of Ultrasonic Estimation of Bladder Volume

Objective: To compare the accuracy of portable and stationary ultrasonography equipment in estimating residual bladder volume. Design: A prospective study. Setting: A rehabilitation hospital affiliated with a medical university in Taiwan. Participants: Sixty-four patients with voiding dysfunction. Interventions: Each patient received both types of ultrasonography, plus catheterization (as the criterion standard for measuring bladder volume). Main Outcome Measures: The mean errors and mean percentage error resulting from use of the 2 types of equipment were recorded. Results: Stationary real-time ultrasonography had a lower absolute error (21.9±25.0mL vs 34.4±38.2mL) and percentage error (13.1%±10.5% vs 36%±52.4%) than the portable ultrasonography (P<.05). Conclusion: Stationary ultrasonography provided a more accurate estimate of residual bladder volumes than did the portable device. However, portable ultrasonography is more convenient to use and has an acceptable accuracy for clinical use.