Ocular hypertension and glaucoma: the contribution of large studies to daily practice

Official guidelines to manage and treat various clinical presentations of glaucoma and ocular hypertension are not currently in wide use. Several well-designed clinical trials have been published recently which can provide ophthalmologists with therapeutic recommendations. In the field of ocular hypertension, three major and historic studies are reported and discussed in this review. A more recent study undertaken in Sweden and the design of the Ocular Hypertension Treatment Study (OHTS) are reviewed as well, although the final results of this important trial have not yet been published. The conclusions of the Collaborative Normal Tension Study Group (CNTSG) have been expected for a long time since this disease is difficult to manage; a 30% reduction in baseline intraocular pressure avoids further deterioration of the visual field in most patients. Other studies have dealt with different strategies in open angle glaucoma. The Advanced Glaucoma Intervention Study (AGIS) has investigated different therapeutic sequences in advanced glaucoma while the Collaborative Initial Glaucoma Treatment Study (CIGTS) and the Early Manifest Glaucoma Trial (EMGT), still in progress, have evaluated the efficacy and safety of surgery versus medical treatment and treatment versus no treatment, respectively, in new and low-grade glaucoma. These long-term studies have led to a better approach to ocular hypertension, normal tension glaucoma, initial glaucoma, and advanced glaucoma. This review presents the characteristics of these clinical studies, points out the problems linked to giving a fair and practical interpretation, and attempts to draw useful guidelines for daily clinical practice.