Diagnosis and Management of Equine Laryngeal Disorders

This disorder occurs mainly in Standardbreds and occasionally in Thoroughbreds. The rostral (free) aspect of the epiglottis becomes trapped in a pouch of mucosa that develops from the mobile sub-epiglottic mucosa. Entrapment may be permanent, intermittent or exercise-induced. If permanent, the entrapping membrane and epiglottic cartilage become swollen and ulcerated. Permanent or intermittent dorsal displacement of the soft palate (DDSP) may occur secondary to epiglottic entrapment. Clinical signs are caused by airflow obstruction and abnormal expiratory noises occur when air fills the pouch that vibrates during expiration. Diagnosis is by endoscopy: an entrapped epiglottis loses its normal flat, serrated appearance and become rounded, thickened and possibly hyperaemic or ulcerated. Additionally, the normally prominent blood vessels on its dorsal aspect of epiglottic cartilage are not visible. If DDSP is present, oral endoscopy or digital oral examinations under sedation can confirm diagnosis. Treatment is by sectioning the entrapping membrane using a long curved hook knife per nasum or more safely per os or by transendoscopic laser sectioning, standing or under GA. Alternatively, resection or axial division of entrapping membrane via laryngotomy under general anaesthesia. […]