Glaucoma is one of the most common causes of visual loss in the United States and affects about three million Americans. A standard medical treatment for newly diagnosed glaucoma is using eye drops and/or laser treatment to lower the pressure inside the eye. However, recent studies of glaucoma treatment had questioned this approach, suggesting that the risk of vision loss from glaucoma could be reduced by instead having immediate surgery, called filtration surgery.
The Collaborative Initial Glaucoma Treatment Study (CIGTS) was designed to address this question by comparing the effects of medical treatment to early filtration surgery in newly diagnosed open-angle glaucoma. The CIGTS found that increased eye pressure--a risk factor for glaucoma—was significantly decreased in both the medically and surgically-treated groups, with the surgery group having a larger decrease. However, in the surgery group, the need for subsequent cataract surgery was significantly higher, and patients were more likely to lose visual acuity (straight ahead vision) and visual field (peripheral vision) during the first few years of followup study. After four years, patients in both groups were similar in visual acuity and visual field. Few patients developed serious vision loss from glaucoma after either treatment.
The CIGTS investigators concluded that the study results provide no reason to change current treatment approaches to glaucoma. The National Eye Institute supports this conclusion.
The CIGTS researchers also compared the impact of these two treatments on the patients' health-related quality of life. Likewise, their findings provide no reason to change current treatment approaches to glaucoma.
Lichter PR, Musch DC, Gillespie BW, Guire KE, Janz NK, Wren PA, Mills RP, CIGTS Study Group. Interim Clinical Outcomes in The Collaborative Initial Glaucoma Treatment Study Comparing Initial Treatment Randomized to Medications or Surgery. Ophthalmology. 2001 Nov. PubMed Janz NK, Wren PA, Lichter PR, Musch DC, Gillespie BW, Guire KE, Mills RP, CIGTS Study Group. The Collaborative Initial Glaucoma Treatment Study: Interim Quality of Life Findings After Initial Medical or Surgical Treatment of Glaucoma. Ophthalmology. 2001 Nov. PubMed