Parapapillary atrophy in patients with focal visual field loss

PURPOSE: To examine parapapillary atrophy in normal subjects and patients w ith primary open-angle glaucoma with focal visual field loss. METHODS: Twenty-nine patients with repeatable early focal visual field loss according to standard automated perimetry (Humphrey program 24-2) and 29 m atched (age and disk area) normal subjects were included. Parapapillary atr ophy area and optic disk topography were evaluated with a confocal scanning laser ophthalmoscope. The difference in parapapillary atrophy area between normal subjects and patients with glaucoma was examined. Optic disk topogr aphy was evaluated by means of the rim-disk area ratio in 36 10-degree sect ors and classified into diffuse and focal patterns of neuroretinal rim thin ning. In patients with a focal pattern, the locations of rim thinning and p arapapillary beta zone atrophy were compared. RESULTS: Beta zone atrophy was detected more frequently in patients with gl aucoma (45% [13/29]) than in normal subjects (7% [2/29]), and it was locate d both superiorly and inferiorly in 92% (12/13) of the glaucoma patients. A lpha zone atrophy was significantly larger in patients with glaucoma than n ormal subjects (P = .009) but not more frequent (97% [28/29] in both groups ). Sixty-one percent (8/13) of glaucoma patients with beta atrophy had diff use thinning and 31% (4/13) had focal thinning. Eight percent (1/13) did no t have neuroretinal rim thinning. In the four patients with both focal rim thinning and beta zone atrophy, the location of rim thinning corresponded t o the location of the beta zone atrophy (100% [4/4]). CONCLUSIONS: In patients with early focal glaucomatous visual field loss, t he presence and location of parapapillary beta zone atrophy and neuroretina l rim thinning are in good correspondence. Observation of localized parapap illary beta zone atrophy in clinical practice should direct one to more clo sely examine the optic disk in this region, as it may reveal localized rim thinning in a disk previously considered to be normal. Moreover, diffuse st ructural change in an eye with only focal functional change, as determined by standard automated perimetry, is consistent with the possibility that st ructural damage may be more widespread than functional damage in these pati ents. (C) 1999 by Elsevier Science Inc. All rights reserved.