AIM: To evaluate and compare the clinical effect of 180 and 360 degrees of selective laser trabeculoplasty(SLT)in treatment of primary open angle glaucoma(POAG).

METHODS: Totally 60 cases(60 eyes)of POAG were treated by SLT with light spot diameter of 400μm, irradiation time of 3 nanosecond, and power of 0.3-1.2mJ. Patients were evaluated 1 hour, 1 day, 1 week, 1 month, 3 and 6 months after laser treatment.

RESULTS: Intraocular pressure(IOP)decreased significantly in two groups after laser treatment. The mean preoperative IOP was(25.6±2.0)mmHg(1kPa=7.5mmHg)in 180-degree SLT group, and(25.4±2.1)mmHg in 360-degree SLT group. The mean IOP at 1 hour, 1 day, 1 week, 1 months, 3 months and 6 months postoperatively were(27.1±2.1)mmHg,(16.5±1.9)mmHg,(19.6±1.9)mmHg,(18.5±1.8)mmHg,(19.9±1.9)mmHg,(20.3±1.8)mmHg, respectively, in 180-degree SLT group, and were(26.6±1.9)mmHg,(15.9±2.0)mmHg,(19.0±2.0)mmHg,(17.8±1.9)mmHg,(18.7±2.0)mmHg,(19.2±1.9)mmHg, respectively, in 360-degree SLT group. There were statistically significant decreases in IOP at 1 day, 1 week, 1 month, 3 months and 6 months postoperatively compared with preoperative IOP in the two groups(P<0.01). To compare the effect of two groups, the 360-degree SLT group showed significantly lower post-treatment IOP at each follow-up point relative to 360-degree SLT group, and its IOP reduction rate stayed statistically higher than the 180-degree group at 3 months and 6 months postoperatively(P<0.05).

CONCLUSION: This study suggests that 360-degree SLT is more effective than 180-degree SLT in treatment of POAG.