REPRODUCIBILITY OF OPTIC-NERVE HEAD TOPOGRAPHIC MEASUREMENTS WITH THEGLAUCOMA-SCOPE

Purpose: Glaucoma is an optic neuropathy in which optic nerve changes are important in diagnosis and progression, because the visual field m ay remain normal even while the optic nerve is undergoing significant damage. Accurate methods to objectively document the appearance of the optic nerve are necessary. In order for an optic disc imaging system to be clinically useful for detecting change, its reproducibility must be established. Methods: We measured the reproducibility of duplicate measurements in 59 eyes of 31 consecutive patients, grouped into glau coma subjects (n = 29) and eyes with glaucoma (n = 30), with the 3.10 OIS Glaucoma-Scope. In order to simulate two visits on one day, sets o f three optic disc images were obtained first, followed by a repeat se t, and the best disc images of each (chosen by the computer) were comp ared. Results: The coefficients of variation of duplicate measurements for glaucoma suspects and patients with glaucoma were respectively: v ertical cup/disc (c/d) ratio, 6.3% and 3.47%; horizontal c/d ratio, 4. 61% and 2.97%; c/d area, 3.29% and 1.37%; cup area, 1.82% and 1.72%; m ean position (MP) disc, 13.3% and 10.42%; MP total, 10.1% and 13.2%. F or three eyes the examination was not possible (opacification of poste rior capsule, miosis). Conclusion: These results suggest that the 3.10 version of the OIS Glaucoma-Scope allows reproducible measurements in living eyes.