Methodological evaluation of ultrasound-guided modified traumatic catheterization in dogs with suspected urothelial carcinoma

Importance: Bladder tumors in dogs, particularly urothelial carcinoma (UC), pose a diagnostic challenge due to overlapping imaging features with benign conditions. Accurate diagnosis is crucial for appropriate treatment and prognosis. Objective: To assess the effectiveness of a modified traumatic catheterization technique using a 4-hole catheter for cytological sampling in dogs with bladder masses. Methods: Fifteen dogs with hematuria and mass-like bladder lesions identified using ultrasonography were included in the study. 15 dogs underwent modified traumatic catheterization using a four-hole catheter created by adding two extra holes to a 6 or 8 Fr feeding tube. The catheter was inserted into the bladder, and cells were aspirated from the lesion under ultrasound guidance. The procedure’s efficacy was evaluated both quantitatively and qualitatively. Results: All 15 cases achieved a 100% cell acquisition rate with high cellularity. The median visualization score was 3/3, the manipulation score was 3/3, and the cellularity score was 2/2. The average procedure time was 8.8 min. Diagnoses included 12 cases of UC and three cases of polypoid cystitis/urinary bladder polyps. No significant adverse effects, including bladder perforation or urethral trauma, were observed. Mild bleeding occurred in some cases but resolved spontaneously. Conclusions and Relevance: Modified traumatic catheterization using a 4-hole catheter is a safe, efficient, and minimally invasive technique for diagnosing UC and other bladder conditions. It is particularly useful for small-sized dogs and those unsuitable for invasive procedures. The enhanced catheter design improves lesion contact and sampling efficiency by offering a valuable tool for veterinary practitioners.