COMPARISON OF METHODS TO EVALUATE THE OPTIC-NERVE HEAD AND NERVE-FIBER LAYER FOR GLAUCOMATOUS CHANGE

PURPOSE: To compare the rates of optic nerve damage in early human gla ucoma as measured by four methods to evaluate change in the optic nerv e and nerve fiber layer. METHODS: Four techniques were used to detect progressive glaucomatous damage in a prospective, longitudinal study: (1) qualitative evaluation of stereoscopic color optic disk photograph s, (2) qualitative evaluation of monochromatic nerve fiber layer photo graphs, (3) manual stereoplanimetric measurements of disk rim area, an d (4) computerized measurement of peripapillary nerve fiber layer heig ht, One eye of each patient with glaucoma or ocular hypertension was e valuated at the beginning and end of a follow up period of not less th an one year, The rates of structural change measured by these techniqu es and the rate of visual field change measured with threshold automat ed perimetry were determined. RESULTS: We followed up 193 patients for a mean (+/- S.D.) of 3.3 +/- 1.0 years (range, one to six years). Twe nty nine (15%) of 193 eyes progressed by qualitative optic disk evalua tion, 14 (7.2%) of 193 eyes progressed by qualitative nerve fiber laye r evaluation, seven (3.6%) of 193 eyes progressed by stereoplanimetry, and 24 (13.2%) of 182 eyes progressed by measurement: of nerve fiber layer height. Visual field deterioration was detected in 12 (5.2%) of 193 patients and correlated best with qualitative optic disk and nerve fiber layer evaluations, Evaluation by stereoplanimetry and nerve fib er layer height measurement detected change in eyes with primarily dif fuse structural damage, a pattern not well detected by qualitative met hods. CONCLUSION: Both qualitative and quantitative methods of optic d isk and nerve fiber layer evaluation contribute to the identification of progressive damage, depending on the stage of disease and the chara cteristics of optic nerve cupping.