EXTERNAL SLT Treatment in Patients With Uncontrolled OPEN ANGLE GLAUCOMA (ETSG)

A Pioneer Study: External Selective Laser Trabeculoplasty for Treating Uncontrolled Open Angle Glaucoma

The purpose of this study is to evaluate the advantages and disadvantages of external selective laser trabeculoplasty (SLT) in treating open angle glaucoma,compared to traditional SLT.

glaucoma is the 2nd leading cause for blindness in the western world.at the time approximately 60 million people are diagnosed as glaucoma patients with an estimated rise of 30% in the next decade. glaucoma is defined as a progressive damage to the optic nerve ,followed by a damage to the visual field. high intraocular pressure (IOP) is considered a main risk factor.lowering IOP can be done in several ways ,including medication ,laser treatment and operations. medical treatment is effective in most cases ,but requires high daily compliance,side effects and availability of medication in living areas. laser trabeculoplasty treatment for reducing IOP is a first line treatment for patients with open angle glaucoma (OAG).with success rate of 70-90%, it can be done as an additive treatment or as a sole treatment. SLT or "cold" laser is a non-invasive treatment in which short wave lengths are being transduced in short intervals ,through a gonioscopic lens to the area of filtering angle. thec wave length is specific to cells rich in melanin (located in the filtering angle). the mechanism of action is regeneration of cytokine surge -causing macrophages recruitment and breakage of inter-cell connections at the trabecular meshwork (filtering area) and allows rise in fluid shift. the treatment requires several lasering to areas at the surrounding the wave does not cause rise in tissue heat or scaring of tissue and can be repeated.among its disadvantages are reduction in affect during time,causing new elevation of IOP , potential peripheral anterior synechia (PAS), corneal erosion or oedema,requires experience in treating through gonioscopic lense. previous reports in the literature regarding external low intensity laser (LIL)show less complication rate. our study evaluates the use of external SLT by using a standard retinal laser machine ,with procedure performed on the outer sclera-above the trabecular meshwork with laser parameters similar to those used in retinal surgeries. this is a prospective, randomized, comparative clinical trial.

intra ocular pressure, open angle glaucoma, selective laser trabeculoplasty, external laser treatment

a success is defined a decrease of >/= 20% in intra ocular pressure measured after treatment -compared to intra ocular pressure measured prior to treatment a relative success in an intra ocular pressure thet is lowered post treatment in less than 20% -compared to pre-treatment. failure is considered as an intra ocular pressure equal or higher than measured prior to treatment

success is defined as no need for suplemental medication for lowering intra ocular pressure ,complete failure is described as using the same amount or more of medication ,relative success in described as a need to use less hypotensive medications for lowering intraocular pressure after the procedure

Inclusion Criteria: Primary Open Angle Glaucoma clinical appearance of pigment at the angle angle assessed as >3 by a professional glaucoma expert IOP above target pressure under full anti-hypertensive treatment with a good compliance for treatment or IOP above target pressure and poor compliance to medical treatment due to: allergic reaction , side effects,physical inability etc. able to sign independently on an informed concent Exclusion Criteria: pregnancy/breast feeding glaucoma not specified as primary open angle glaucoma sensitivity to on or more of the medications in the study current /past intraocular inflammation primary open angle glaucoma with out appearance of pigment at the angle s/p laser trabeculoplasty at treatment eye inability to sign an informed concent

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