Interventional treatment of benign nasopharyngeal stenosis and imperforate nasopharynx in dogs and cats: 46 cases (2005-2013).

OBJECTIVE To determine outcome for dogs and cats with benign nasopharyngeal stenosis or an imperforate nasopharynx that underwent balloon dilatation or metallic stent placement. DESIGN Retrospective case series. ANIMALS 15 dogs and 31 cats. PROCEDURES Medical records were retrospectively reviewed, and data on signalment, history, clinical signs, lesion location, treatment, and outcome were obtained. Patients were excluded if < 6 months of follow-up information was available. RESULTS 5 dogs and 22 cats underwent balloon dilatation, and results were successful in 11 (0 dogs and 11 cats) of the 27 (41%). Stents were placed in 34 patients (including 15 in which balloon dilatation had been unsuccessful). Uncovered stents were placed in 30 patients, and results were successful in 20 (67%). Covered stents were placed in 11 patients (including 7 in which uncovered stent placement was unsuccessful), and results were successful in all 11. Twenty-three of the 34 (68%) patients in which stents were placed developed complications. The most common complications were tissue ingrowth (n = 10), chronic infection (7), and stent fracture (5) for the 30 patients with uncovered stents and chronic infection (8) and oronasal fistula (3) for the 11 patients with covered stents. Overall, outcome was successful in 36 of the 46 (78%) patients (median follow-up time, 24 months; range, 2 to 109 months). CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that in dogs and cats, nasopharyngeal stenosis and imperforate nasopharynx can be successfully treated with balloon dilatation or stent placement, but that there was a high risk of failure with balloon dilatation alone and a high risk of complications regardless of procedure.