Clinical evaluation of retinal nerve fiber layer atrophy in glaucoma--correlation between visual field damage and the...

The purpose of this report is to clarify the clinical significance of nerve fiber layer atrophy (NFA) in the diagnosis of glaucoma. The assessment was made only in the arcuate area, named F1 and F2 sectors. First, 29 eyes with glaucoma were evaluated. Rim/disc ratios were calculated in each the F1 and F2 sectors. The sensitivity corresponding to the F1 and F2 sectors was determined by automatic perimeter (Octopus). Each sector was divided into three subsectors in relation to the distance from the disc margin. Retinal sensitivity in the proximal subsector was closely correlated with the rim/disc ratio in the corresponding sector and with the enlargement of glaucomatous cupping. NFA was expressed as a proximal, a distal or a total atrophy pattern. Proximal and distal visual field damage was prone to be associated with the proximal and distal NFA type respectively. Second, we examined photographs of 784 normal eyes and 50 glaucomatous eyes. The difference in the ratio of appearance of NFA was statistically significant between the 20-30s and 40-60s age groups, and between the C/D ratio less than 0.5 and C/D ratio greater than 0.5 groups. The appearance of the NFA was also classified into five patterns, according to the width. Almost all the NFAs in the normal eyes showed milder patterns, whereas almost all the NFAs in the glaucoma group showed stronger patterns. It was suggested that one of the mechanisms that causes NFA in glaucoma was a strong nerve fiber drop out that differed from aging such as local circulatory disturbance. The findings indicate that the visual field damage in glaucoma can be estimated from the funduscopic appearance of NFA.