Surgical excision of iridociliary tumors using a postero-anterior cyclo-iridectomy and thermocautery in two dogs.

Abstract

OBJECTIVE: To report the surgical excision of an iridociliary adenoma and iridal melanocytoma using a postero-anterior cyclo-iridectomy in two dogs. PROCEDURE: A 7 year old neutered male English springer spaniel (case 1) and a 7 year old neutered male Labrador mix (case 2) were presented for evaluation of an intrairidal mass OS. RESULTS: Complete ophthalmic examination revealed a large, dorsonasal, well-demarcated, intrairidal mass OS. A tan to pink intrairidal mass extending into the iridocorneal angle (case 1) and a pigmented intrairidal mass (case 2) were present. B-mode ultrasonography showed a focal, soft tissue, homogenous mass within the uvea adjacent to and contacting the lens. Neither pars plana involvement nor vitreal extension was present. A postero-anterior cyclo-iridectomy was performed through a polyhedral scleral flap. Thermocautery was used to complete the cyclo-iridectomy (case 1) and partial iridectomy (case 2) to excise the mass en bloc. Histopathology revealed a completely excised iridociliary adenoma (case 1) and iris melanocytoma (case 2). The surgery sites healed without complication. Mild uveitis (cases 1 and 2), scant vitreal hemorrhage (case 1), and mild hyphema (case 2) were present three days postoperatively but had resolved ten days postoperatively. The patients remain visual twenty-two months (case 1) and seven months (case 2) postoperatively with a normal intraocular examination other than an iridal defect and mild dorsonasal lens capsular opacities. CONCLUSIONS: The surgical approach described in these cases is utilized in physician-based medicine. This approach and the use of thermocautery provide a viable surgical option for excision of large iridociliary tumors in dogs.