J Korean Ophthalmol Soc.  2014 Apr;55(4):563-569.

Short-Term Clinical Outcomes of Laser Trabeculoplasty Using a 577-nm Wavelength Laser

• Kim JM
• Cho KJ
• Kyung SE
• Chang MH

Abstract

PURPOSE
To evaluate the pressure-lowering effects of single-spot laser trabeculoplasty and patterned laser trabeculoplasty using a 577-nm wavelength laser.
METHODS
A total 35 eyes of 35 patients with primary open-angle glaucoma were enrolled in this study. Eighteen eyes of 18 patients were treated with 360degrees single-spot laser trabeculoplasty and 17 eyes of 17 patients were treated with 360degrees patterned laser trabeculoplasty. All patients were evaluated after laser trabeculoplasty at 1 week, 1 month, 3 months, and 6 months using slit lamp examination and Goldmann applanation tonometry.
RESULTS
At 6 months postoperatively, the single-spot laser trabeculoplasty group had a mean IOP of 15.89 +/- 3.89 mm Hg with a mean IOP reduction of 37.1%, while the patterned laser trabeculoplasty group had a mean IOP of 17.57 +/- 2.64 mm Hg with a mean IOP reduction of 27.1%.
CONCLUSIONS
Laser trabeculoplasty with a 577-nm optically pumped semiconductor laser was safe and demonstrated an IOP lowering effect. There were no significant differences in the IOP lowering effects between the single-spot laser trabeculoplasty and the patterned laser trabeculoplasty.

Keyword

Laser trabeculoplasty; PASCAL; Pattern laser trabeculoplasty

MeSH Terms

Glaucoma, Open-Angle
Humans
Lasers, Semiconductor
Manometry
Trabeculectomy*

Figure

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  Figure 1. Graphic user interface for patterned laser trabeculoplasty software.

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  Figure 2. Procedure of patterned laser trabeculoplasty. (A) Schematic view of patterned laser trabeculoplasty. Pattern of Aiming beam (635 nm) is projected on trabecular meshwork. Once a physician presses the foot pedal, PASCAL photo-coagulator delivers a patterned laser on trabecular meshwork. (B) After shooting the laser, the pattern is automatically ro-tated clockwise by 11.25˚. (C) Gonioscopic view of patterned laser trabeculoplasty.

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  Figure 3. Changes in mean intraocular pressure after laser trabeculoplasty. No statistical differences between the groups during follow-up (p > 0.05, Mann-Whitney test). SLT = single spot laser trabeculoplasty; PLT = patterned laser trabeculoplasty.

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  Figure 4. Kaplan-Meier survival curve using success defi-nition in single spot laser trabeculoplasty and patterned laser trabeculoplasty groups. No statistical differences between the groups during follow-up (p = 0.93). Cum = cumulative; SLT = single spot laser trabeculoplasty; PLT = patterned laser trabeculoplasty.

Reference

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