OCT 03, 2011
To learn more about the long-term course of visual field progression among treated primary angle closure glaucoma (PACG) patients, researchers retrospectively evaluated outcomes among 57 patients treated at the Singapore National Eye Centre and who had at least 10 years of follow-up. All patients were Chinese, with a mean age of 60.
Progression of a VF defect was defined as a change of ≥4 from baseline on two consecutive VF tests. VF progression occurred in 32.5 percent of patients over an average of five years, with 7 percent progressing to blindness based on VA and VF test criteria respectively, despite treatment and follow-up for glaucoma at a large tertiary referral eye hospital. Cox regression analysis showed eyes with VF progression had a higher mean overall IOP (P < .001), and higher prevalence of previous acute angle closure (AAC) (AAC, P = .008). This finding may be attributable to the development of peripheral anterior synechiae and or angle damage resulting from the AAC episode. It is unlikely that the VF progression was the result of the AAC episode itself, as the follow-up period was more than 10 years.
The VF progression rate reported in this study is similar to that reported for POAG, which has been cited between 21 percent and 44 percent over 10 years and between 16 percent and 37 percent over five years. Interestingly, progression to blindness occurred only in 5 percent to 7 percent of PACG patients in this study compared to 10 percent to 30 percent in other studies on POAG. While more study is required, this report provides novel insights about the long-term progression rates among Chinese PACG patients.