METHODS: Fifty-one eyes of 27 patients 51 eye with POAG were included in this retrospective study. All the cases were divided into three groups depending on the mean deviation(MD): the early stage group(MD>-6dB, 15 eyes), middle stage group(-12dB≤MD≤-6dB, 15 eyes)and late stage group(MD<-12dB, 21 eyes). All subjects underwent SLT on 360° of the angle between July 2018 to March 2020. The laser parameters of a 532nm, Q-switched, frequency-doubled Nd: YAG laser, with 3ns pulse time, 400μm spot diameter were set to selectively target pigmented trabecular meshwork cells without visible damage to the adjacent non-pigmented tissue. Intraocular pressure(IOP)reduction was observed at 1h, 1d, 1, 3, 6 and 12mo after the laser procedure. Meanwhile, the ratio of the IOP reduction, visual field index(VFI), MD, medication, adverse reactions and efficiency were assessed as well.

RESULTS: Within the 12mo post-SLT, there were no statistically significant differences for the IOP and IOP decline rate between each group(all P>0.05). There were significant differences in VFI and MD among early, middle and late groups(P<0.001), within the 12mo post-SLT, no statistically significant differences were detected for the decline of VFI and MD in each group. In terms of the early stage group, the effective rates of SLT at 1, 3, 6 and 12mo after treatment were 100%, 93%, 87%, 67%, respectively. For the middle stage group and late stage group, the effective rates were 87%, 80%, 93%, 60%, and 67%, 71%, 62%, 19%, respectively.

CONCLUSION: SLT was an effective treatment for POAG patients in various stages, while the effective rate decreased with time.