Balloon dilation and transient stenting of unilateral membranous choanal atresia in a British Shorthair cat with chronic purulent rhinitis and ascending meningoencephalitis.

Choanal atresia is a rare congenital anomaly in humans and animals, characterized by the absence of communication of one or both nasal cavities with the nasopharynx. The severity of clinical signs depends on the presence of unilateral versus bilateral stenosis as well as comorbidities. With bilateral atresia, respiration may be severely compromised particularly during sleep, as airflow can only occur when breathing through the open mouth.