Progress in glaucoma treatment research: a nonrandomized prospective study of 102 patients with advanced refractory glaucoma treated by Leksell gamma knife irradiation

Abstract

Object.The authors performed a study to characterize the effects of ciliary body gamma knife surgery (GKS) for advanced glaucoma.Methods.In addition to a pilot project involving 14 patients, 88 other patients were treated. Four 8-mm isocenters were used. Blind eyes received 20 Gy to the 50% isodose. If there was preserved vision the dose was 15 Gy. The median follow up was 20 months (range 2–54 months).Severe pain was present in 93% of patients with secondary glaucoma; after GKS it was substantially improved in 89% of cases. In primary open angle glaucoma, the pain was less frequent and severe. In more than half the patients it disappeared during a median latency of 6 weeks. The median intraocular pressure value was lowered in patients with secondary glaucoma (from 51.3–27 mm Hg). The same values for primary glaucoma were 25.3 and 16.1 mm Hg, respectively, after a median latency of 12 weeks. Twenty-seven of 40 patients with neovascular glaucoma showed a marked reduction of neovascularization after a median latency of 18 weeks. Treatment complications were slight. There was postoperative lacrimation in 61%. Two patients underwent postirradiation cataract extraction. Noninfectious keratitis was observed in two patients. Pharmacotherapy could be reduced in all patients and ceased in approximately one third. There has been no recurrence of the initial symptoms and no worsening of visual acuity.Conclusions.Gamma knife surgery ameliorates the main symptoms in advanced glaucomas and precludes the need for eventual ocular enucleation.