Glaucomatous optic disc changes in the contralateral eye of unilateral normal pressure glaucoma patients

Objective: To evaluate the optic disc for structural abnormalities in the c ontralateral eye of unilateral normal pressure glaucoma patients. Design: Cross-sectional study. Participants: Fifty-three unilateral normal pressure glaucoma patients. Testing: Optic disc imaging with the Heidelberg Retina Tomograph (HRT). Main Outcome Measures: Optic disc structural parameters. Results: Of the contralateral (normal visual field) eyes, 79.2% were found to have an abnormal optic disc by HRT analysis. Of the glaucomatous (abnorm al visual field) eyes, 94.3% were found to have an abnormal disc. The patte rns of disc abnormality were defined as marked or moderate diffuse thinning of the neuroretinal rim (NRR) or broad or narrow focal thinning of the NRR . The most common pattern in the contralateral eyes was moderate diffuse th inning of the NRR (45.2%), The most frequently abnormal segments were the n asal superior (73.8%) followed by the nasal inferior and the global NRR par ameter (both 54.8%). Conclusions: A high frequency of NRR thinning was found in the contralatera l (normal visual field) eyes of unilateral normal pressure glaucoma patient s by HRT analysis. Knowing whether these abnormalities predict future progr ession to the development of visual field abnormality must wait until longi tudinal studies are completed, if a disc abnormality is shown to predict fu ture field loss, then early identification will allow early treatment. (C) 2000 by the American Academy of Ophthalmology.