Diagnosis and minimally invasive surgery of epiglottic diseases in horses. Part 1: Subepiglottic cysts

摘要

From 1977 to 2001 eighteen horses with subepiglottic cysts were presented to the Equine Clinic of the School of Veterinary Medicine Hannover. The diagnosis was made by clinical examination, endoscopy and radiography. Additionally, an ultrasound examination of the linguo-epiglottic region was performed on one horse under general anaesthesia. The cysts were 1 to 6 cm in diameter and led to respiratory noise (44 percent, 8/18), cough (61 percent, 11/18) and dysphagia (28 percent, 5/18). Various minimally invasive techniques were developed which allowed successful excision of the cysts. Treatment could be performed perorally under general anaesthesia using an unheated wire snare or electrosurgical wire snares. The wire snares could also be positionedthrough an endoscopic channel, either perorally under general anaesthesia, or, alternatively, transnasally; transnasal surgery with visual monitoring of the process was possible in sedated horses. A further method was cystectomy performed with a Nd:YAG laser using a bare fiber in contact mode. The excision of the cysts was successful in all treated cases. In only one case a postoperative complication (dorsal displacement of the soft palate) occurred. The method of choice was the transnasal excision of accessible cysts by means of electrosurgical wire snares in sedated horses. Patients of poor compliance or with inaccessible cysts could also be treated successfully with an electrosurgical wire snare applied transorally or transnasally under general anaesthesia. The laser surgical excision proved to be comparatively risky due to the thermal effect on the epiglottis. As shown in the present study laryngotomy is, in many cases, avoidable for the surgical therapy of subepiglottic cysts.