Evaluation of preoperative ultrasonographic parameters to predict renal recovery in long-term survivors after treatment of feline ureteral obstructions: 2012-2019.

OBJECTIVES

The aim of this study was to determine whether preoperative ultrasound imaging characteristic(s) in cats suffering from unilateral benign ureteral obstructions are predictive of outcome after successful renal decompression with a subcutaneous ureteral bypass (SUB) device.

METHODS

This was a retrospective study of 37 cats with unilateral, benign ureteral obstruction. Preoperative imaging characteristics (including renal pelvis diameter, parenchymal thickness [transverse plane], renal length and pelvic size:overall renal size) and biochemical data were evaluated for all cats diagnosed with a unilateral ureteral obstruction treated with a SUB device. Any patient with bilateral obstructions or documented bacteriuria/infection in the data collection period was excluded. All patients were followed between 3 and 6 months postoperatively to obtain postoperative biochemical data. Long-term outcome was defined as serum creatinine concentration at 3-6 months postoperatively.

RESULTS

No preoperative imaging characteristics or biochemical findings were found to be significantly associated with long-term serum creatinine concentrations. The length of the kidney was found to be associated with change in blood urea nitrogen and creatinine with decompression but not with long-term renal values.

CONCLUSIONS AND RELEVANCE: In this study, long-term renal function based on preoperative ultrasound imaging findings could not be predicted in cats with unilateral ureteral obstruction, regardless of the severity of the biochemical parameters, renal pelvic dilation (large or small pelvis), kidney size or thickness of renal parenchyma assessed.