Use of a three-dimensional ultrasound device for noninvasive urine bladder volume measurement in dogs and cats.

Abstract

BACKGROUND: Evaluation of urinary bladder volume (UBV) in companion animals is largely underused although it could be of clinical importance for diagnosis of micturition disorders. Advances in medical technology have led to the development of 3-dimensional (3D) ultrasound bladder scanners. HYPOTHESIS/OBJECTIVES: Assess the agreement between UBVs measured using a new noninvasive 3D ultrasound bladder scanner (Portascan 3D, ref MD-6000) and the actual UBV in dogs and cats. ANIMALS: Between December 2021 and June 2023, dogs and cats undergoing urinary catheterization for diagnostic or therapeutic reasons were prospectively enrolled. METHODS: For each animal, signalment, urinalysis, and bladder content abnormalities identified on conventional 2-dimensional ultrasound examination were recorded. Agreement between UBV measurements obtained using the 3D ultrasound device and those obtained by catheterization (reference standard) was quantified using Bland-Altman analysis. RESULTS: Nineteen dogs and 15 cats were enrolled. Bland-Altman analysis determined that the 3D ultrasound bladder scanner underestimated UBV by -6.1% (95% CI, -14.9% to +2.8%) in dogs and overestimated UBV by +13.6% (95% CI, +3.9% to +23.2%) in cats. The analysis also found excellent concordance and reproducibility between the 2 methods, with Lin's concordance correlation coefficient of 0.99 (95% CI, 0.96-1.00) in dogs and 0.89 (95% CI, 0.66-0.97) in cats. CONCLUSIONS AND CLINICAL IMPORTANCE: The 3D ultrasound scanner represents a noninvasive, rapid, and easy-to-use method that provides accurate measurements of UBV in dogs and cats.