Transendoscopic contact neodymium:yttrium aluminum garnet laser treatment of tympany of the auditory tube diverticulum in two foals.

Tympany of the auditory tube diverticulum was treated in 2 Standardbred foals by fenestrating the median septum, using an endoscopically placed Nd:YAG laser. Recurrence in 1 foal was treated by enlarging the fenestration, using a modified Whitehouse approach, and the pharyngeal opening of the auditory tube. Use of the Nd:YAG laser eliminates the risk of inadvertent cranial nerve damage associated with incisions into the auditory tube diverticulum. The procedure can be performed with the horse sedated or anesthetized. Clinical signs can recur in the fenestration heals closed or if the condition is bilateral rather than unilateral.