Fluoroscopic Assessment of Pharyngeal Collapse in Dogs and Its Association With Age, Breed, and Tracheal and Bronchial Collapse

Background: Pharyngeal collapse (PC) is a relatively common condition in brachycephalic dogs and often coexists with other airway collapses, including tracheal collapse (TC) and bronchial collapse (BC). However, the relationship between PC severity, clinical signs, and other forms of airway collapse is not well understood. Objectives: Evaluate the correlation between PC severity and clinical signs, the severity of other airway collapse, and demographic factors such as breed and age. Animals: Ninety-five client-owned dogs. Methods: A retrospective review of medical records was conducted at Seoul National University Veterinary Medical Teaching Hospital from April 8 to September 5, 2024. The severity of PC and TC, and the presence of BC, cervical lung lobe herniation, and tracheal kinking were evaluated using fluoroscopy. Medical records were reviewed for data on signalment, respiratory clinical signs, and body condition score. Correlations between PC severity and other factors were analyzed using Pearson's correlation coefficient. Results: Severity of PC had a significant positive correlation with clinical signs, particularly cyanosis or respiratory distress, as well as age and brachycephalic conformation (Pearson's r, 0.26, 0.30, 0.46, respectively; p value, < 0.05 for all). No significant positive correlation was found between PC severity and TC or BC. Conclusions and Clinical Importance: Fluoroscopic assessment of PC severity is clinically relevant, especially in older and brachycephalic dogs. Our study emphasizes the value of fluoroscopic evaluation as a tool for assessing the severity of PC, aiding in the diagnosis and management of affected dogs.