Cyclocryotherapy for refractory glaucoma after penetrating keratoplasty

Twenty-eight patients (28 eyes) with secondary glaucoma following penetrating keratoplasty and failed to respond to anti-glaucoma drugs and routine filtering procedures were performed with cyclocryotherapy by nitrogen monoxide. All patients were followed up for more than one year. The results showed intraocular pressure was well controlled in 89% of the eyes, graft remained clear in 85%, and visual functions are preserved in 82% of the patients. Our study suggests that precisely controlled temperature, time, and extent of cryotherapy, and post-operative anti-rejection agents be the key factor to success. Over-treatment, which may lead to atrophy of the eye, must be avoided. It should not be given up flowing under-treatment in the initial procedure.