Ultrasound-guided transurethral urinary bladder biopsy using an endoscopic biopsy forceps: 27 cases (2016-2019).

OBJECTIVES: To describe an ultrasound-guided transurethral bladder biopsy technique using endoscopic forceps and its results in dogs of different sizes with different lesion locations. MATERIALS AND METHODS: Medical records of dogs that underwent ultrasound-guided transurethral bladder biopsy with endoscopic forceps were retrospectively reviewed. Patient signalment, lesion location, use of urinary catheter as a guide, outcome of the procedure and histopathology results were retrieved. RESULTS: Twenty-seven dogs underwent this procedure. Biopsy samples were successfully obtained in 23 dogs. Insertion of the endoscopic forceps without a urinary catheter allowed the procedure to be performed in patients with a small urethral diameter without complication. The procedure was unsuccessful in dogs with a urethral diameter smaller than the outer diameter of the biopsy forceps (i.e. 1.8 mm), either due to small patient size or obstructive urethral lesion. All biopsy samples allowed histopathological diagnosis. No complications were reported after the procedure. CLINICAL SIGNIFICANCE: This non-invasive biopsy technique should be considered in patients with bladder lesions in which histopathological diagnosis is needed, especially when endoscopic examination is not feasible. By use of the Doppler mode, biopsy retrieval was safe also when the lesion ​was highly vascularised.