Laser trabeculoplasty for open angle glaucoma
Editorial Group: Cochrane Eyes and Vision Group
Published Online: 17 OCT 2007
Assessed as up-to-date: 16 AUG 2007
Copyright © 2009 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Rolim de Moura CR, Paranhos Jr A, Wormald R. Laser trabeculoplasty for open angle glaucoma. Cochrane Database of Systematic Reviews 2007, Issue 4. Art. No.: CD003919. DOI: 10.1002/14651858.CD003919.pub2.
- Publication Status: Edited (no change to conclusions)
- Published Online: 17 OCT 2007
Open angle glaucoma (OAG) is an important cause of blindness worldwide. Laser trabeculoplasty, a treatment modality, still does not have a clear position in the treatment sequence.
The objective of this review was to study the effects of laser trabeculoplasty for OAG.
We identified trials from CENTRAL in The Cochrane Library, MEDLINE, EMBASE, LILACS and manual searching. We also contacted researchers in the field.
We included randomised controlled trials comparing laser trabeculoplasty with no intervention, with medical treatment, or with surgery. We also included trials comparing different technical modalities of laser trabeculoplasty.
Data collection and analysis
Two authors independently assessed trial quality and extracted the data. We contacted trial investigators for missing information.
This review included 19 trials involving 2137 participants. Only five trials fulfilled the criteria of good methodological quality. One trial compared laser trabeculoplasty with topical beta-blocker to no intervention in early glaucoma. The risk of glaucoma progression was higher in the control group at six years of follow up (risk ratio (RR) 0.71 95% confidence interval (CI) 0.53 to 0.95). No difference in health-related quality of life was observed between the two groups. Three trials compared laser trabeculoplasty to medication (regimens used before the 1990s) in people with newly diagnosed OAG. The risk of uncontrolled intraocular pressure (IOP) was higher in the medication group compared to the trabeculoplasty group at six months and two years of follow up. Three trials compared laser trabeculoplasty with trabeculectomy. The risk of uncontrolled IOP was significantly higher in the trabeculoplasty group at six months but significant heterogeneity was observed at two years. Diode and selective laser are compared to argon laser trabeculoplasty in three trials and there is some evidence showing a comparable effect in controlling IOP at six months and one year of follow up.
Evidence suggests that, in people with newly diagnosed OAG, the risk of uncontrolled IOP is higher in people treated with medication used before the 1990s when compared to laser trabeculoplasty at two years follow up. Trabeculoplasty is less effective than trabeculectomy in controlling IOP at six months and two years follow up. Different laser technology and protocol modalities were compared to the traditional laser trabeculoplasty and more evidence is necessary to determine if they are equivalent or not. There is no evidence to determine the effectiveness of laser trabeculoplasty compared to contemporary medication (prostaglandin analogues, topical anhydrase inhibitors and alpha2-agonists) and also with contemporary surgical techniques. Also there should be further investigation in to the effectiveness of laser trabeculoplasty in specific racial groups, specific diagnostic groups, such as pseudoexfoliation and pigmentary glaucoma and different stages of OAG. More research is also required determining cost-effectiveness of laser trabeculoplasty in the management of glaucoma.
Plain language summary
Laser trabeculoplasty for open angle glaucoma
Glaucoma is a chronic progressive disease of the optic nerve which, if not treated, leads to visual field decay and blindness at end stages. Intraocular pressure (IOP) decreasing is shown to diminish the progression of the disease, and could be achieved by the chronic use of hypotensive eyedrops, incisional surgery or laser trabeculoplasty. There is still great controversy about where in the treatment scale laser trabeculoplasty is positioned, although this technique has already been described three decades ago. This treatment consists of application of laser spots in the trabecular meshwork, the structure responsible for the aqueous humor drainage, leading to an increase in the outflow facility through it and in consequence, decreasing IOP. It is an interesting form of treatment since it does not depend on chronic instillation of eyedrops, as does medical treatment, and also does not have too many complications, as does incisional surgery. This review included 19 trials (2137 participants). One trial compared laser trabeculoplasty associated with a hypotensive eyedrop with no intervention, and at six years of follow up the risk of visual field decay was greater in non treated participants. Three trials compared hypotensive eyedrops with trabeculoplasty, and the risk of uncontrolled IOP was greater at two years in the laser group. It is necessary to mention that the eyedrops used in these trials differ significantly from the ones used currently, since these trials were developed a decade ago. Three other trials compared trabeculoplasty with trabeculectomy and the risk of uncontrolled IOP was higher in the laser group at six months of follow up. There is some evidence showing that diode laser and selective trabeculoplasty have similar effect in controlling IOP when compared to argon laser trabeculoplasty. Comparisons of different lasers and different techniques of application were done in the remaining trials, but there is still not enough evidence to determine which is the best treatment protocol. Further research is necessary to compare trabeculoplasty with new hypotensive eyedrops and also the results of laser therapy in people of different ethnicities, since some studies suggest that they have a different response to this kind of laser therapy. More research is required to analyse cost-effectiveness of these interventions.
在全世界，隅角開放型青光眼（Open angle glaucoma (OAG)）是造成失明的重要原因之一。雷射小樑成型術是一種治療方式，但是其治療結果仍未有清楚的定位。
我們從Cochrane Library中的CENTRAL、以及MEDLINE、 EMBASE、LILACS和手查過程中尋找臨床試驗。我們也連絡了該領域的研究者。
這篇回顧納入19篇試驗，包含2137名研究對象。只有五篇研究完全符合方法學品質良好的標準。一篇試驗是比較雷射小樑成型術與局部的β阻斷劑對照無介入措施用於治療早期青光眼。六年追蹤期間，對照組發展成青光眼的風險較高（risk ratio (RR)為0.71，95% confidence interval (CI)為0.53 至0.95）。兩組的健康相關生活品質沒有顯著差異。三篇試驗比較雷射小樑成型術與藥物（1990年代以前使用的方案）用於治療新診斷為隅角開放型青光眼的病患。在六個月與兩年的追蹤期間，相較於雷射小樑成型術，藥物組眼壓失控（intraocular pressure (IOP)）的風險較高。三篇試驗比較雷射小樑成型術與小樑切除術。六個月時小樑成型術組其眼壓失控的風險顯著較高，但兩年時則沒有觀察到顯著的差質。三篇試驗比較半導體與選擇性雷射對照氬氣雷射小樑成型術，有些證據顯示在六個月與一年的追蹤時其控制眼壓的效果相同。