Study: Blindness often follows acute primary angle closure attack

With a mean follow-up of more than 6 years after acute primary angle closure, almost 20% of patients in an Asian population were blind in the attack eye, a study in Singapore found. In addition, almost half of the study subjects had glaucomatous optic nerve damage.

Tin Aung, MD, and colleagues at the Singapore National Eye Centre performed this observational case series to determine the long-term outcome after acute angle closure attacks in Asian eyes. The researchers recalled 90 people who were initially seen with an acute attack of primary angle closure 4 to 10 years previously. The study subjects were Asian and predominantly Chinese. All participants underwent a complete eye examination at the follow-up visit. Optic discs were evaluated by a masked examiner for glaucomatous optic neuropathy. The main outcome measures were blindness (defined as best-corrected visual acuity worse than 6/60 or central visual field loss of less than 20· in the attack eye). The mean age of the participants was 62 years at the time of the initial attack, and mean follow-up was 6.3 years.

Sixteen participants (17.8%) were blind in the attack eye, and in half of these the blindness was caused by glaucoma. Glaucomatous optic nerve damage was seen in 43 participants (47.8%), and of these, 13 eyes had markedly cupped optic discs. Cataract was responsible for close to half the cases of poor vision; 38 eyes (58%) had a BCVA of worse than 6/9.

The authors did not find any identifiable risk factors related to the acute attack that were significantly associated with the presence of glaucomatous optic neuropathy.

The study is published in the August issue of Ophthalmology.