Summary
Brachycephalic breeds are usually distinguished from mesocephalic and dolichocephalic breeds by their shortened skull and open orbitae. Upper respiratory syndrome has been described in brachycephalic dogs. Clinical signs usually include snoring, inspiratory dyspnea, exercise intolerance, stridor, cyanosis, and even syncopal episodes in more severe cases. In brachycephalic animals, in relation to the nose, the ala is too large and presses against the septum from the lateral aspect, leading to obstruction of the nasal vestibule. In addition to soft palate hyperplasia, nasopharyngeal mucosa can show considerable hyperplasia, as demonstrated in CT and endoscopic studies, and this contributes to dramatic nasopharyngeal obstruction. The correlation between respiratory and digestive disorders suggests an influence of upper respiratory tract diseases on gastroesophageal diseases, and vice versa. Techniques of surgical correction have been described for most of the anatomic abnormalities contributing to brachycephalic syndrome.
