Purpose: To determine the long-term outcome of Asian eyes with an acute attack of primary angle closure (APAC) and to identify risk factors at presentation associated with the development of glaucomatous optic nerve damage.
Design: Cross-sectional observational case series.
Participants: Ninety individuals who were initially seen with APAC 4 to 10 years previously at 2 Singapore hospitals.
Methods: All subjects underwent a complete eye examination, including visual acuity, visual field testing, dilated eye examination, and optic nerve head photography. The optic discs were judged clinically and photographically as to whether there was glaucomatous optic neuropathy present, and visual fields were assessed for corresponding visual field loss. All visual fields and optic nerve photographs underwent a second evaluation by an experienced, but masked, glaucoma specialist, who assessed whether the changes were compatible with glaucoma.
Main outcome measures: The main outcome measures were blindness (defined as best-corrected visual acuity worse than 6/60 and/or central visual field of less than 20 degrees in the attack eye) and glaucomatous optic neuropathy (GON).
Results: A total of 90 of 170 eligible subjects (65.2%) were examined. All subjects were Asian and were predominantly Chinese (78 subjects [86.7%]). There were 61 females (67.8%), and the age of the subjects was 62.0+/-9.0 years (mean +/- standard deviation) at the time of APAC, with a mean duration of 6.3+/-1.5 years from the time of the APAC episode to the study examination. Sixteen (17.8%) subjects were blind in the attack eye; half of the cases of blindness were caused by glaucoma. Forty-three subjects (47.8%) had GON, with 13 eyes (15.5%) having markedly cupped optic discs (cup-to-disc ratio >0.9). Thirty-eight eyes (58%) had best-corrected vision worse than 6/9, with cataract responsible for close to half the cases of poor vision. There were no identifiable risk factors related to the APAC episode that were significantly associated with the presence of GON.
Conclusions: Several years after being seen with APAC, 17.8% of subjects examined were blind in the attack eye, and almost half had glaucomatous optic nerve damage. Vision was also reduced in a large number of individuals, largely from unoperated cataract. Subjects with APAC would benefit from regular follow-up to monitor for visual field decline and glaucoma development.