CASE DESCRIPTION A 4-year-old spayed female Beagle was evaluated because of a 2-month history of intermittent pollakiuria, stranguria, dysuria, and abdominal pain. A diagnosis of bacterial cystitis was initially made, but clinical signs persisted despite appropriate antimicrobial treatment, so the dog was referred for further evaluation and treatment.
CLINICAL FINDINGS Abdominal ultrasonography revealed a large, thin-walled, cystic structure in the urinary bladder at the level of the expected right ureterovesicular junction that communicated with the uniformly dilated right ureter. Severe right-sided pyelectasia was also detected. A presumptive diagnosis was made of a right-sided orthotopic ureterocele with secondary hydroureter and pyelectasia.
TREATMENT AND OUTCOME Cystoscopy revealed a large cystic structure in the region of the right ureterovesicular junction without obvious communication between the ureter and urinary bladder. Portable C-arm fluoroscopy was used to confirm the presence of an intramural orthotopic tract and to measure the diameter of the ureter and renal pelvis via retrograde contrast ureteropyelography. Complete laser ablation of the ureterocele was performed by incising it circumferentially near its base. Clinical signs resolved immediately following the procedure. Six weeks later, the dog remained free of clinical signs and abdominal ultrasonography revealed resolution of hydroureter with persistence of mild right-sided pyelectasia.
CLINICAL RELEVANCE Cystoscopic-guided laser ablation of an orthotopic ureterocele secondary to ureterovesicular stenosis was a safe and effective minimally invasive treatment for the dog of this report, resulting in immediate and continued improvement of clinical signs and ultrasonographic changes. Laser ablation should be considered as an alternative to surgery for the treatment of orthotopic ureteroceles in dogs.
Objective—To evaluate interobserver agreement and diagnostic accuracy of brain MRI in dogs.
Procedures—5 board-certified veterinary radiologists with variable MRI experience interpreted transverse T2-weighted (T2w), T2w fluid-attenuated inversion recovery (FLAIR), and T1-weighted-FLAIR; transverse, sagittal, and dorsal T2w; and T1-weighted-FLAIR postcontrast brain sequences (1.5 T). Several imaging parameters were scored, including the following: lesion (present or absent), lesion characteristics (axial localization, mass effect, edema, hemorrhage, and cavitation), contrast enhancement characteristics, and most likely diagnosis (normal, neoplastic, inflammatory, vascular, metabolic or toxic, or other). Magnetic resonance imaging diagnoses were determined initially without patient information and then repeated, providing history and signalment. For all cases and readers, MRI diagnoses were compared with final diagnoses established with results from histologic examination (when available) or with other pertinent clinical data (CSF analysis, clinical response to treatment, or MRI follow-up). Magnetic resonance scores were compared between examiners with κ statistics.
Results—Reading agreement was substantial to almost perfect (0.64 < κ < 0.86) when identifying a brain lesion on MRI; fair to moderate (0.14 < κ < 0.60) when interpreting hemorrhage, edema, and pattern of contrast enhancement; fair to substantial (0.22 < κ < 0.74) for dural tail sign and categorization of margins of enhancement; and moderate to substantial (0.40 < κ < 0.78) for axial localization, presence of mass effect, cavitation, intensity, and distribution of enhancement. Interobserver agreement was moderate to substantial for categories of diagnosis (0.56 < κ < 0.69), and agreement with the final diagnosis was substantial regardless of whether patient information was (0.65 < κ < 0.76) or was not (0.65 < κ < 0.68) provided.
Conclusions and Clinical Relevance—The present study found that whereas some MRI features such as edema and hemorrhage were interpreted less consistently, radiologists were reasonably constant and accurate when providing diagnoses.