Abstract
Purpose: :
To evaluate whether the intraocular pressure response from the application of selective laser trabeculoplasty (SLT) in one eye can be used to predict response to the treatment in the fellow eye in patients with primary open angle glaucoma.
Methods: :
A retrospective medical record review was conducted on 28 patients with primary open-angle glaucoma (POAG) who underwent bilateral SLT either simultaneously or on two separate occasions. Intraocular pressures were measured pre treatment and at 6 weeks post treatment. The following parameters were calculated for subjects who underwent SLT on separate occasions: the unadjusted IOP difference (pre-laser IOP minus post-laser IOP) for both eyes; the adjusted IOP difference (unadjusted pretreatment IOP minus post treatment IOP minus comparable IOP change in the fellow eye). The relationship between the unadjusted and adjusted IOP difference of first treated eye and second treated eye in patients who underwent SLT on two separate occasions and between unadjusted IOP difference between two eyes in subjects who underwent simultaneous SLT was studied using coefficient of determination (r2).
Results: :
Twelve patients meeting study inclusion criteria had sequential SLT. Mean IOP readings in the first treated eye pre- and post- SLT were 19.2 (SD 16.9-21.5) and 13.9 (SD 11.6-16.2) p=.0026, respectively. In the second treated eye, the pre- and post-SLT IOP readings were 19.1 (SD 15.6-22.5) and 14.2 (SD 10.7-17.6) p=.047, respectively. The r2 value for the unadjusted difference in IOP between the two eyes was 0.36 (p=.03)and adjusted difference in IOP was 0.75 (p=.0014) respectively. Sixteen patients meeting study inclusion criteria underwent simultaneous SLT. Mean IOP readings in the right eye pre- and post-SLT were 18.7 (16.2-20.8) and 15.4 (13.2-17.5) p=.038, respectively. Mean IOP readings in the left eye pre- and post-SLT were 18.0 (16.1 -20.1) and 15.4 (13.4-17.5) p=.07, respectively. The r2 value for the adjusted IOP difference in IOP between the two eyes was 0.93 (p=<.0001).
Conclusions: :
Our retrospective data suggests that there may be a moderate correlation between pressure responses from SLT between eyes in a particular patient. This data may be useful in treatment planning and expectations following this procedure.
Keywords: laser • intraocular pressure