At all follow-up visits , IOP was reduced less in the CG group than in the POAG group ( 24.8 % + / - 11.15 vs. 27.7 % + / - 9.91 at 6 months , 22.0 % + / - 6.66 vs. 30.6 % + / - 6.35 at 12 months , and 31.4 % + / - 5.55 vs. 35.1 % + / - 1.75 at 18 months ) , but the difference was significant only at 12 months .
