Nasopharyngeal cicatrices in horses: 47 cases (1972-1985)

Nasopharyngeal cicatrices were observed endoscopically in 47 horses examined because of abnormal respiratory noises and/or exercise intolerance. A review of these cases revealed a correlation between cicatrization and age, sex, and the presence of other upper airway abnormalities. The age of affected horses ranged from 6 to 21 years, with a mean age of 12.7 +/- 7.8 (+/- 2 SD) years. Females were affected 2.7 times more frequently than males. Abnormalities commonly observed with a nasopharyngeal cicatrix included chondritis of the arytenoid cartilage, epiglottic deformity, and deformity of the guttural pouch openings. The nasopharyngeal cicatrix was responsible for respiratory obstruction in only 3 horses. Treatment for the cicatrix was not performed on any horse in this series. Generalized nasopharyngeal and laryngeal inflammation were postulated as causes of the cicatrices and associated abnormalities.