Laser trabeculoplasty and subthreshold transscleral cyclophotocoagulation – the new therapeutic options are modifying therapeutic algorithm in glaucoma Review article

Abstract

Selective laser trabeculoplasty (SLT) and micropulse laser trabeculoplasty (MLT) are well established, non-invasive laser procedures in glaucoma, but their place in the therapeutic algorithm still evolves. Lately published multicenter randomized clinical trials indicate the need to consider laser trabeculoplasty as the first-line treatment before medications in primary open-angle glaucoma an ocular hypertension due to its favorable safety profile, efficacy and cost-effectiveness. Subthreshold transscleral cyclophotocoagulation (present on the market under different brand names: SubCyclo® TS-CPC [Quantel, France] or Cyclo G6® mTS-CPC [Iridex, USA]) is an antiglaucomatous laser procedure, recently arousing more and more interest in ophthalmologists as a new non-invasive method in our therapeutic portfolio. This new device utilizes 810 nm diode laser beam, fractionated into ultra-short pulses, resulting in low energy spots without causing ciliary body coagulation. Subthreshold (or subliminal) energy delivered during the session spares the tissue due to very limited local heat accumulation zone and therefore this procedure may be repeated. Laser energy partially disables aqueous producing ciliary epithelium and opens supraciliary space thus activating the additional outflow facility. Subthreshold TS-CPC in several clinical trials proved to be effective in lowering the intraocular pressure and devoid of significant sight threatening side effects, comparing to the classical thermal diode cyclophotocoagulation method.