OPTIC DISC MORPHOLOGY IN AGE-RELATED ATROPHIC GLAUCOMA

Background: This study was performed in order to evaluate whether, in primary open-angle glaucoma (POAG), patients with a different degree o f fundus tessellation vary in optic disc morphology and level of intra ocular pressure Methods: Color stereo optic disc photographs of 562 pa tients with POAG and a myopic refractive error of less than -8 diopter s were morphometrically examined. According to the degree of fundus te ssellation, the total group was divided into a tessellated subgroup (n = 256) and a nontessellated subgroup (n = 306,) both matched for neur oretinal rim area and refractive error Results: In the tessellated sub group, as compared to the nontessellated subgroup, the mean maximal in traocular pressure values were significantly lower, the parapapillary atrophy was significantly larger, the optic cup was significantly more shallows, frequency of disc hemorrhages was lower, the mean visual fi eld defect was significantly mon marked, and patient age was significa ntly higher. Within the whole study group, the degree of fundus tessel lation increased significantly (P<0.005) with decreasing mean maximal intraocular pressure, decreasing optic cup depth, and increasing degre e of parapapillary atrophy. In the subgroups with the highest degree o f fundus tessellation, parapapillary atrophy was the greatest and the mean maximal intraocular pressure was the lowest compared to other sub groups Conclusion: At the low-pressure end of POAG, marked fundus tess ellation is associated with large parapapillary atrophy, shallow disc cupping, mostly concentric emaciation of the neuroretinal rim, and hig h patient age. The results suggest a distinct subtype of POAG in older patients with relatively low intraocular pressure leading to a mainly diffuse atrophy of the optic nerve.