Prevalence of Intraocular Pressure Spikes and 6 Months of Intraocular Pressure Control in Patients Undergoing Selective Laser Trabeculoplasty

Abstract

Purpose: : IOP spike is a known complication following ALT, however there is little data reporting IOP spike following SLT. This study will report the prevalence of IOP spike following SLT and IOP control at 6 months. SLT is an alternative therapy to ALT as a method to treat uncontrolled open-angle Glaucoma. In several studies, SLT has shown superior safety to ALT and equivocal efficacy to both ALT and topical medical treatment. SLT targets the pigmented trabecular meshwork (TM) without damaging the surrounding non-pigmented tissue. Unlike ALT, SLT is a repeatable procedure and can even be used after failed ALT.

Methods: : This is a retrospective study reviewing 344 charts of patients with uncontrolled glaucoma in need of laser trabeculoplasty. 344 eyes were treated. Each eye was treated with a Nd:YAG laser with 56-100 spots, 400 microns in size, placed over 180-360 degrees covering both pigmented and nonpigmented TM with energy levels ranging from 0.7-0.9 mW. Alphagan prophylaxis was given to each patient prior to the procedure. IOP spike was defined as 5 mmHg above pre-laser IOP. IOP was measured using Goldmann applanation. IOP and number of medications were measured after 1 hour, 2 months, and 6 months.

Results: : There were 344 eyes and 344 patients that were studied. Of the 344, patients 286 were African American, 36 were Caucasian and 22 were of a different race. There were 223 female and 121 male patients. The average age was 69.6 years. The mean pre-op IOP was 20.0 mmHg ± 4.8 mmHg. The mean post-op IOP was 18.4 mmHg ± 5.4 mmHg. Of the 344 eyes, only 7 (2.0%) had one hour post-op IOP spikes. When looking at 6 months follow-up, the average IOP for patients without IOP spike was 18.6 mmHg ± 6.36 mmHg, while those who did have IOP spike had IOP equal to 17.4 mmHg ± 2.9mmHg at 6 months. Equally, the number of medications needed to control IOP at 6 months was similar in both groups, 2 ± 1 medications pre- and post-op.

Conclusions: : SLT was shown to be effective in reducing IOP in patients with POAG. Only 7/344 (2.0%) patients developed an IOP spike at one hour. Six months post SLT there was no statistical difference In IOP or number of medications between those who did and did not have an IOP spike.

Keywords: intraocular pressure • laser • inflow/ciliary body