3, 24 There is also evidence of TM cell division following both ALT and SLT. 3, 22, 24 The TM following SLT was intact except for cracks in the corneoscleral sheets and a few endothelial cells with disrupted intracytoplasmic pigment granules and vacuoles. 23 Histological studies have demonstrated minimal coagulative or mechanical damage. The mechanism of action of SLT is not fully understood, although it is believed that it is more cellular and less mechanical or thermal, 22 with macrophages from the spleen recruited into the TM via cytokines to remove debris from the TM. 20 It has also been reported to dissolve an iris pigment epithelial cyst. 16 SLT has also been reported to be utilized after unsuccessful reduction of IOP after iridotomy, 17 deep sclerectomy, 18 trabectome, 19 and after retinal detachment repair with silicone oil. 15 It has been found to be effective in juvenile OAG patients as well. 13, 14 SLT has also been proven to be helpful in treating steroid-induced glaucoma or as prophylaxis for anticipated steroid-induced glaucoma. It is indicated for low-tension glaucoma, reducing not only IOP but diurnal fluctuation of IOP. Although SLT was initially indicated for OAG, pseudoexfoliation, and pigmentary glaucomas, SLT has been utilized for a wide variety of glaucomas. 10 SLT was also found to be comparable to 11 and in some reports more efficacious 12 than ALT. SLT is also safe as initial therapy in OAG and in patients with ocular hypertension. 6 – 8 SLT has been shown to be safe in adults, 9 and the complication rate is extremely low. SLT has a variable success rate (40%–70%) in adults. The incidence of iritis and elevated IOP is much lower compared to ALT. Because SLT selectively targets the pigmented TM cells and has an energy level 1% of ALT, it is a gentler laser than ALT with no histologic scarring or coagulative damage to the TM, 3, 4 thus reducing collateral damage to surrounding tissues and making repeat treatments possible. SLT has a very short pulse duration (3 ns), which is shorter than the thermal relaxation time of melanin, allowing for selective photothermolysis. SLT is a laser treatment that can reduce IOP in patients with open-angle glaucoma (OAG). Selective laser trabeculoplasty (SLT) was developed in 1999 by Latina and Park 2 as an alternative to ALT. It also coagulated the trabecular meshwork (TM) tissue, resulting in peripheral anterior synechiae. Although successful, ALT had several side effects, most notably elevated IOP and inflammation. It was an adjunct as well as a supplement to topical and oral medications. Modes of treatment include medications, laser, or intraocular surgery.Īrgon laser trabeculoplasty (ALT) was developed by Wise and Witter 1 in the 1970s. Glaucoma is an optic neuropathy in which intraocular pressures (IOPs) that are too high for the eye can result in optic nerve damage, subsequently leading to peripheral or central visual field loss.
0 kommentar(er)
