The Accuracy of 2D versus 3D Ultrasoundin Bladder Volume Measurement duringUrodynamic Studies: A Literature Review

Abstract

Accurate assessment of bladder volume plays a significant role in diagnosing and managing lower urinary tract dysfunctions, particularly during urodynamic (UD) evaluations. Although catheter-based UD studies are widely accepted as the gold standard, they are invasive, operator-dependent, and often uncomfortable for patients. This has led to increased interest in non-invasive alternatives such as two-dimensional (2D) and three-dimensional (3D) ultrasound (US) imaging. This review compares the diagnostic performance, accuracy, and clinical feasibility of 2D and 3D US technologies in the context of bladder volume measurement during or alongside UD assessments. A structured literature search was conducted across PubMed, Google Scholar, and Web of Science for studies published between 1998 and 2024. Inclusion criteria focused on peer-reviewed articles reporting bladder volume estimation using 2D or 3D US, particularly those providing direct or indirect comparisons to reference standards such as catheterization or post-void residual volume. Findings suggest that 3D US offers improved spatial accuracy, reduced operator dependency, and greater potential for automation and wearable integration compared to 2D US. However, methodological heterogeneity and the limited number of direct head-to-head comparison studies remain
key limitations. These findings underscore the need for large-scale comparative trials and standardized imaging protocols to validate 3D US as a primary diagnostic tool in UDs. With further refinement, 3D US holds strong potential as a non-invasive, patient-centered solution for bladder function assessment.