Comparison of laser trabeculostimulation with laser trabeculoplasty in open-angle glaucoma

We compared a new method, laser trabeculostimulation (LTS), with laser trabeculoplasty (LTP). The technique LTS stimulates trabecular meshwork tissue and thereby increases the outflow facility. The method LTP causes shrinkage and cicatrization of the meshwork tissue, thus limiting the reduction in postoperative intraocular pressure (IOP). The mean preoperative IOP of 40 eyes was 24.9 +/- 6.8 mmHg (mean +/- standard deviation). The LTS was applied with a 50-microns spot size, a power setting of 50mW, and an exposure time of 1 sec. With LTS, the IOP decreased and then increased afterward. Low power (50mW) was effective if used for a longer duration. The LTS can be applied repeatedly and used in addition to conventional LTP. The overall effect achieved with LTS was less than that with LTP, but it is possible to reduce IOP by selecting more reasonable parameters, e.g., a laser setting of 200mW, a 50 microns spot size and a 0.5 to 1-sec duration.