Subepiglottic cysts are sometimes seen at the back of the pharynx and soft palate. They are an uncommon cause of respiratory noise in young horses. Although they are usually present from birth, they often remain undetected until the horse begins exercise training. Signs include respiratory noise and exercise intolerance. Large cysts may produce coughing, difficulty swallowing, and inhalation of foreign materials in foals. The condition is diagnosed by endoscopic examination of the upper respiratory tract. Treatment involves complete removal of the lining of the cyst. Rupture of the cyst will temporarily “deflate” it, but recurrence is common.
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