Abstract
Purpose :
Selective laser trabeculoplasty (SLT) may be used as the sole primary treatment for glaucoma or may be performed in an effort to augment the IOP reducing effect of one or more topical antiglaucoma agents. This study sets out to determine whether there may be any association between the number of pre-established concurrent topical medications with the extent of IOP reduction attainable via SLT.
Methods :
Clinical records for eyes undergoing SLT laser during a 4-year interval were divided into 3 groups: A) on no medication, B) on one topical antiglaucoma agent, and C) on two or more such agents. Applanation IOP was assessed as the average of 2 measurements at pre-treatment baseline and 3 months post-SLT. Differences from baseline for the entire population and for each subgroup were evaluated by paired t-test, and differences in IOP response between the three subgroups were assessed by non-paired t-test. Two eyes exhibiting any sustained post-laser uveitic response were excluded from analysis; all others were included. All eyes received standard SLT titration starting at 0.9mJ with ~100 spots over 360 degrees using Ellex SLT and Latina lens.
Results :
45 eyes of 39 patients (22F, 17M; mean 64y; 26R,19L) were treated. Groups A, B & C comprised 22, 9 and 14 eyes, respectively.
A significant difference in IOP reduction was noted at 3 months between:
group A(n=22) vs B(n=9); [-3.0(+/-0.7) vs -6.9(+/-1.0); delta -3.9mmHg; P=0.009]
group A vs composite B&C(n=23); [-3.0(+/-0.7) vs -6.3(+/-1.0); delta -3.1mmHg; P=0.020]
group A vs C (n=14); [-3.0(+/-0.7) vs -5.9(+/-1.4); delta -2.9mmHg;P=0.048]
There was no significant difference in IOP at baseline between the three groups;
(A (20.9+/-1.1) vs B (22.2+/-1.2) P=0.45); (A vs C (21.3+/-2.0) P=0.89)
Conclusions :
Contrary to our inital assumption that coexisting topical therapy might blunt the IOP reducing effect of SLT, our data indicate that the converse appears to be true. IOP reduction in eyes under topical therapy was two-fold greater than in eyes that had no prior history of IOP-reducing therapy, regardless of the number of topical agents being applied.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.