Contrast-enhanced voiding urosonography: A new, radiation-free, alternative method for imaging of urinary bladder and urethra in healthy dogs

Intraluminal Contrast-Enhanced Ultrasonography Application in Dogs and Cats

Administering intraluminal fluid can improve the acoustic window for the visualization of the lumen and wall layers in the cavitary organs. Microbubbles in ultrasound contrast agents can also be used for intracavitary applications to enhance visualization of the lesion in human patients. However, there was no literature extending the clinical application of intraluminal contrast-enhanced ultrasonography (CEUS) to patients with naturally occurring diseases in veterinary medicine. This case series aims to describe the detailed application and diagnostic value of intraluminal CEUS in six clinical cases with naturally occurring gastrointestinal (GI) and urinary tract diseases.

Diagnosis of traumatic urethral stricture in a canine patient with contrast-enhanced voiding urosonography : A case report

A 5-year-old intact male mixed-breed dog presented with a 3-day history of stranguria and dysuria. Results of physical examination, plain radiographs, and ultrasonography were consistent with a traumatic urethral stricture in the prescrotal urethra just under the previous trauma region, resulting in partial obstruction of urine outflow. Contrast-enhanced voiding urosonography (CE-VUS) was performed, and a urethral stricture was confirmed. The dog underwent surgery. A scrotal urethrostomy was performed. After 3 days of hospitalization, the dog was discharged from the Clinic. Based on an extensive literature review, this is the first report using CE-VUS to evaluate urethral pathology in a canine patient.

Diagnostic yield of uroendoscopy compared to ultrasonography for evaluating lower urinary tract disorders in dogs

Background

Cystourethroscopy and vaginoscopy (uroendoscopy) is often used in the diagnostic evaluation of dogs with lower urinary tract disorders (LUTD).

Objective/Hypothesis

To evaluate if uroendoscopy is warranted in dogs with various LUTD, the agreement between uroendoscopic and ultrasonographic diagnoses were compared. Dogs with recurrent urinary tract infections (rUTI) will have the highest diagnostic agreement between uroendoscopy and ultrasonography (US) compared to dogs presenting for other LUTD.

Animals

Two hundred thirty‐seven dogs presenting between 2014 and 2019 with lower urinary tract signs (LUTS) that had US within 60 days preceding uroendoscopy.

Methods

Retrospective study. Dogs were categorized by primary indication for ultrasound. Pertinent uroendoscopic findings were recorded and agreements (κ analysis) between the final uroendoscopic diagnosis were compared with the final ultrasonographic diagnosis.

Results

Pertinent uroendoscopic findings were recorded for 69/237 (29%) cases. For dogs presenting primarily for urinary incontinence (UI), agreement between uroendoscopy and US was 71% (46/65; κ = 0.47, 95% CI 0.28‐0.66), for dogs with stranguria, 58% (29/50; κ = 0.47, 95% CI 0.31‐0.62) and for dogs with rUTI the agreement was substantial at 87% (26/30; κ = 0.70, 95% CI 0.43‐0.98). Urethral strictures were the majority (14/21; 67%) of pertinent uroendoscopic findings for dogs with stranguria, of which 12 were male dogs.

Conclusions and Clinical Importance

Agreement between uroendoscopy and US was moderate for all dogs. Based on these data, recommendation for uroendoscopy should be tailored to individual clinical presentation and signalment; transabdominal US is not the preferred modality for urethral lesions.