Five-year follow up of selective laser trabeculoplasty in Chinese eyes

Evolution of first-line glaucoma therapy, 2007-2018: a population-based analysis

OBJECTIVE

To evaluate the long-term evolution of first-line glaucoma therapy (FLGT) initiated by ophthalmologists and optometrists.

DESIGN

Retrospective population-based study using validated provincial health care databases.

PARTICIPANTS

194,759 Ontario residents, 66 years of age or older, who received FLGT between 2007 and 2018.

METHODS

A total of 194,759 individuals from 12 annual cohorts were enrolled, and rates of first-line medical treatment (prostaglandin analogue [PGA], beta-blocker, alpha-2-agonist, and carbonic anhydrase inhibitor) and laser trabeculoplasty (LT) were calculated. Provider (ophthalmologist or optometrist) rates also were assessed.

RESULTS

Across the entire study period, of the 194,759 enrolled individuals who received FLGT, 60.2% initially received medical treatment and 39.8% underwent LT. Approximately 94.6% were treated by ophthalmologists. PGA therapy was the most common therapy prior to 2010, whereupon LT became the most common FLGT. By 2015, LT exceeded the total of all medications as FLGT. The annual rate of initial medication prescriptions by optometrists rose to 101.4 per 100,000 population between 2011 and 2018. In 2018, PGA and non-PGA prescription rates by ophthalmologists were 2.6 and 5.0 times higher, respectively, than prescription rates by optometrists.

CONCLUSION

LT therapy has become the most common FLGT for Ontario residents 66 years of age or older. PGAs remain the most frequently prescribed glaucoma medication. While ophthalmologists continue to provide the majority of FLGT, optometrists now provide a small but growing fraction of FLGT following the introduction of glaucoma medication prescribing privileges.

Alternatives to Topical Glaucoma Medication for Glaucoma Management

Topical glaucoma medications have favorable safety and efficacy, but their use is limited by factors such as side effects, nonadherence, costs, ocular surface disease, intraocular pressure fluctuations, diminished quality of life, and the inherent difficulty of penetrating the corneal surface. Although traditionally these limitations have been accepted as an inevitable part of glaucoma treatment, a rapidly-evolving arena of minimally invasive surgical and laser interventions has initiated the beginnings of a reevaluation of the glaucoma treatment paradigm. This reevaluation encompasses an overall shift away from the reactive, topical-medication-first default and a shift toward earlier intervention with laser or surgical therapies such as selective laser trabeculoplasty, sustained-release drug delivery, and micro-invasive glaucoma surgery. Aside from favorable safety, these interventions may have clinically important attributes such as consistent IOP control, cost-effectiveness, independence from patient adherence, prevention of disease progression, and improved quality of life.

Choroidal detachment and hypotony following selective laser trabeculoplasty: a case report

BACKGROUND

Selective laser trabeculoplasty (SLT) is relatively safe and effective in lowering intraocular pressure (IOP). However, although rare, complications can occur after SLT. This report describes a patient with choroidal detachment due to hypotony following SLT without anterior chamber (AC) inflammation.

CASE PRESENTATION

A 67-year-old man was referred for elevated IOP in his left eye with advanced glaucomatous visual field loss. He had previously been diagnosed with idiopathic uveitic glaucoma in the left eye, for which he underwent laser iridotomy, trabeculectomy, and cataract surgery. At the first visit, the IOP of his left eye measured by Goldmann tonometry was 28 mmHg despite maximally tolerated medical treatment. SLT was performed in his left eye, resulting in an IOP of 7 mmHg 7 days later. At 3 weeks post-procedure, the patient experienced ocular pain and decreased visual acuity in his left eye. Slit-lamp examination revealed deep anterior chamber depth and no inflammation reaction, but the IOP in his left eye was 4 mmHg, and both fundus and B-scan ultrasonography showed serous choroidal detachment. All anti-glaucoma agents were stopped, and the patient was started on treatment with oral prednisolone and cyclopentolate eye drops. Three weeks later, choroidal detachment had resolved and the IOP in his left eye had stabilized at 8 mmHg. Follow-up 3 months later showed that the IOP in his left eye remained stable.

CONCLUSIONS

Choroidal detachment-related hypotony is a rare complication of SLT. This possible complication following SLT should be informed to the patients and considered when performing the procedure.

A Randomized, Controlled Comparison of 180 Versus 360 Degrees Selective Laser Trabeculoplasty in Open Angle Glaucoma and Glaucoma Suspects

PRCIS

Three hundred sixty degrees selective laser trabeculoplasty (SLT) produces greater intraocular pressure (IOP) lowering effects with no changes in safety profile compared with 180 degrees SLT.

PURPOSE

To determine whether there is any difference in the IOP lowering effects and safety profiles of 180 versus 360 degrees SLT, using a paired-eye design to limit confounders.

METHODS

This single-center randomized control trial included patients presenting with treatment naïve open angle glaucoma or glaucoma suspects. Once enrolled, 1 eye was randomized to 180 degrees SLT, and the other was treated with 360 degrees SLT. Patients were followed for 1 year and assessed for change in visual acuity, Goldmann IOP, Humphrey visual fields, retinal nerve fiber layer thickness, optical coherence tomography derived cup to disc ratio, and any adverse events or requirements for additional medical interventions.

RESULTS

A total of 40 patients (80 eyes) were included in the study. IOP in the 180 degrees group was reduced from 25.3±2.3 mm Hg to 21.5±2.7 mm Hg, and in the 360 degrees group, from 25.5±2.1 mm Hg to 19.9±2.6 mm Hg ( P <0.01), both at 1 year. There was no significant difference in the number of adverse events or serious adverse events in the 2 groups. There were no statistically significant differences in visual acuity, Humphrey visual field mean deviation, retinal nerve fiber layer thickness, or C:D ratio at 1-year follow-up.

CONCLUSION

At 1 year, 360 degrees SLT was more efficacious at lowering IOP compared with 180 degrees SLT with a similar safety profile in patients with open angle glaucoma and glaucoma suspects. Further studies are needed to determine the long-term effects.

Tetrapodal ZnO-Based Composite Stents for Minimally Invasive Glaucoma Surgery

The glaucoma burden increases continuously and is estimated to affect more than 100 million people by 2040. As there is currently no cure to restore the optic nerve damage caused by glaucoma, the only controllable parameter is the intraocular pressure (IOP). In recent years, minimally invasive glaucoma surgery (MIGS) has emerged as an alternative to traditional treatments. It uses micro-sized drainage stents that are inserted through a small incision, minimizing the trauma to the tissue and reducing surgical and postoperative recovery time. However, a major challenge for MIGS devices is foreign body reaction and fibrosis, which can lead to a complete failure of the device. In this work, the antifibrotic potential of tetrapodal ZnO (t-ZnO) microparticles used as an additive is elucidated by using rat embryonic fibroblasts as a model. A simple, direct solvent-free process for the fabrication of stents with an outer diameter of 200-400 μm is presented, in which a high amount of t-ZnO particles (45-75 wt %) is mixed into polydimethylsiloxane (PDMS) and a highly viscous polymer/particle mixture is extruded. The fabricated stents possess increased elastic modulus compared to pure PDMS while remaining flexible to adapt to the curvature of an eye. In vitro experiments showed that the fibroblast cell viability was inhibited to 43 ± 3% when stents with 75 wt % t-ZnO were used. The results indicate that cell inhibiting properties can be attributed to an increased amount of protruding t-ZnO particles on the stent surface, leading to an increase in local contacts with cells and a disruption of the cell membrane. As a secondary mechanism, the released Zn ions could also contribute to the cell-inhibiting properties in the close vicinity of the stent surface. Overall, the fabrication method and the antifibrotic and mechanical properties of developed stents make them promising for application in MIGS.

Five-year outcomes of selective laser trabeculoplasty: A retrospective study

Introduction

Studies have shown the efficacy of selective laser trabeculoplasty (SLT) to lower intraocular pressure (IOP) as adjuvant therapy during short-term follow-up. However, few studies have assessed the long-term efficacy of SLT on preventing worsening Humphrey visual field (HVF) parameters and thinning of the retinal nerve fiber layer (RNFL) with continued medical therapy.

Methods

A retrospective chart review was conducted of 51 eyes of 39 patients with glaucoma treated with SLT at Boston Medical Center between 2012 and 2016 with 3- and 5-year follow-up. Outcome measures included IOP, visual acuity, number of glaucoma medications, number of months to subsequent surgical intervention. HVF outcome measures included mean deviation (MD) and pattern standard deviation (PSD). Optical coherence tomography (OCT) outcome measures included RNFL mean thickness, and superior and inferior thicknesses.

Results

Twenty-five eyes received subsequent surgical intervention (mean time to intervention = 33.6 ± 20.0 months). In the eyes that did not receive another intervention, mean IOP was significantly decreased by 3.2 and 3.5 mmHg at 3- and 5-year after SLT, respectively. Mean number of glaucoma medications was significantly increased at 5-year (2.7 ± 1.6; P = 0.04), compared to pre-SLT (2.0 ± 1.1). Mean HVF MD was significantly higher at 5-year (-7.64 ± 6.57 dB) compared to pre-SLT (-5.61 ± 3.90 dB). Mean PSD significantly increased at 3-year (5.30 ± 2.91 dB) and 5-year (6.84 ± 2.62 dB), compared to pre-SLT (4.63 ± 2.70 dB; P = 0.04 and ≤0.01, respectively). On OCT, inferior quadrant RNFL thickness decreased significantly at 5-year (88.5 ± 19.3 μm), compared to pre-SLT (94.0 ± 23.2 μm).

Discussion

Although 51% of eyes had IOP controlled at 5-year post-SLT, mean number of glaucoma medications was significantly higher. Also, there was progression of MD and PSD on HVF and inferior quadrant thinning on OCT at 5-year. We found a significant association between age at SLT and risk of subsequent surgical intervention over 5-year follow-up. Our study adds to our understanding of long-term outcomes of adjuvant SLT for glaucoma patients receiving medical therapy.

Effectiveness of selective laser trabeculoplasty and its safety on corneal endothelium in patients with primary open angle glaucoma and ocular hypertension

BACKGROUND AND AIM

The aim of this study was to evaluate the effectiveness of selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT), and to assess its effects and safety on corneal endothelial cell morphology.

PATIENTS AND METHODS

Forty patients with POAG (15 cases, 23 eyes) and OHT (25 cases, 48 eyes) were prospectively evaluated. All cases underwent pachymetry, goniolens examination, Humphrey Visual Field Test, Optical Coherence Tomography, and Corneal Confocal Microscopy measurements. Patients whose intraocular pressure (IOP) was more than 21 mmHg in POAG and OHT, underwent SLT. SLT treatment was applied to the inferior 180° region of the trabecular meshwork. Central corneal thickness (CCT), IOP, and specular microscopy examinations were taken at the visits before and after the first day, first week, first month, third and sixth months of the SLT procedure. Retinal nerve fiber layer (RNFL) thickness measurements and visual field tests were performed before and six month post-SLT. Results of the pre-SLT and post-SLT measurements were compared and a P value of lower than 0.05 was considered statistically significant.

RESULTS

The results of IOP measurements at first week, first month, third, and sixth month post-SLT were significantly lower than the results before and post-SLT first day. No significant difference was found between the results of initial and final measurements of CCT and specular microscopic corneal endothelial cell morphology evaluation. There was no statistically significant difference between the results of initial and final measurements for RNFL thickness and the results of the visual field tests.

CONCLUSION

SLT is an effective treatment modality for reducing IOP in patients with POAG and OHT and is also a safe procedure in terms of the entirety of corneal endothelial cell morphology.

Laser trabeculoplasty for open-angle glaucoma and ocular hypertension

BACKGROUND

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.

OBJECTIVES

To assess the effects of laser trabeculoplasty for treating OAG and ocular hypertension (OHT) when compared to medication, glaucoma surgery or no intervention. We also wished to compare the effectiveness of different laser trabeculoplasty technologies for treating OAG and OHT.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2021, Issue 10); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; LILACS, ClinicalTrials.gov and the WHO ICTRP. The date of the search was 28 October 2021. We also contacted researchers in the field.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing laser trabeculoplasty with no intervention, with medical treatment, or with surgery in people with OAG or OHT. We also included trials comparing different types of laser trabeculoplasty technologies.

DATA COLLECTION AND ANALYSIS

We used standard methods expected by Cochrane. Two authors screened search results and extracted data independently. We considered the following outcomes at 24 months: failure to control intraocular pressure (IOP), failure to stabilise visual field progression, failure to stabilise optic neuropathy progression, adverse effects, quality of life, and costs. We graded the 'certainty' of the evidence using GRADE.

MAIN RESULTS

We included 40 studies (5613 eyes of 4028 people) in this review. The majority of the studies were conducted in Europe and in the USA. Most of the studies were at risk of performance and/or detection bias as they were unmasked. None of the studies were judged as having low risk of bias for all domains. We did not identify any studies of laser trabeculoplasty alone versus no intervention. Laser trabeculoplasty versus medication Fourteen studies compared laser trabeculoplasty with medication in either people with primary OAG (7 studies) or primary or secondary OAG (7 studies); five of the 14 studies also included participants with OHT. Six studies used argon laser trabeculoplasty and eight studies used selective laser trabeculoplasty. There was considerable clinical and methodological diversity in these studies leading to statistical heterogeneity in results for the primary outcome "failure to control IOP" at 24 months.  Risk ratios (RRs) ranged from 0.43 in favour of laser trabeculoplasty to 1.87 in favour of medication (5 studies, I2 = 89%). Studies of argon laser compared with medication were more likely to show a beneficial effect compared with studies of selective laser (test for interaction P = 0.0001) but the argon laser studies were older and the medication comparator group in those studies may have been less effective. We considered this to be low-certainty evidence because the trials were at risk of bias (they were not masked) and there was unexplained heterogeneity. There was evidence from two studies (624 eyes) that argon laser treatment was associated with less failure to stabilise visual field progression compared with medication (7% versus 11%, RR 0.70, 95% CI 0.42 to 1.16) at 24 months and one further large recent study of selective laser also reported a reduced risk of failure at 48 months (17% versus 26%) RR 0.65, 95% CI 0.52 to 0.81, 1178 eyes). We judged this outcome as moderate-certainty evidence, downgrading for risk of bias. There was only very low-certainty evidence on optic neuropathy progression. Adverse effects were more commonly seen in the laser trabeculoplasty group including peripheral anterior synechiae (PAS) associated with argon laser (32% versus 26%, RR 11.74, 95% CI 5.94 to 23.22; 624 eyes; 2 RCTs; low-certainty evidence); 5% of participants treated with laser in three studies of selective laser group had early IOP spikes (moderate-certainty evidence). One UK-based study provided moderate-certainty evidence that laser trabeculoplasty was more cost-effective.  Laser trabeculoplasty versus trabeculectomy Three studies compared laser trabeculoplasty with trabeculectomy. All three studies enrolled participants with OAG (primary or secondary) and used argon laser. People receiving laser trabeculoplasty may have a higher risk of uncontrolled IOP at 24 months compared with people receiving trabeculectomy (16% versus 8%, RR 2.12, 95% CI 1.44 to 3.11; 901 eyes; 2 RCTs). We judged this to be low-certainty evidence because of risk of bias (trials were not masked) and there was inconsistency between the two trials (I2 = 68%). There was limited evidence on visual field progression suggesting a higher risk of failure with laser trabeculoplasty. There was no information on optic neuropathy progression, quality of life or costs. PAS formation and IOP spikes were not reported but in one study trabeculectomy was associated with an increased risk of cataract (RR 1.78, 95% CI 1.46 to 2.16) (very low-certainty evidence).

AUTHORS' CONCLUSIONS

Laser trabeculoplasty may work better than topical medication in slowing down the progression of open-angle glaucoma (rate of visual field loss) and may be similar to modern eye drops in controlling eye pressure at a lower cost. It is not associated with serious unwanted effects, particularly for the newer types of trabeculoplasty, such as selective laser trabeculoplasty.

Energy Dose-Response in Selective Laser Trabeculoplasty: A Review

PRCIS

A literature review of selective laser trabeculoplasty (SLT) energy dose-response found no definitive relationship between intraocular pressure (IOP) reduction with respect to total or pulse energy, race, pigmentation, or application pattern.

PURPOSE

SLT is a safe and effective treatment for lowering IOP. Although evidence is mounting for the advantage of its use as a first-line treatment for IOP reduction, the SLT procedures in use vary widely. The purpose of this literature review was to investigate whether there were any relationships between SLT energy and efficacy for lowering IOP in the published literature.

METHODS

A literature review was undertaken that included studies in which energy levels required for successful SLT treatment were investigated: in general, with respect to angle pigmentation, race or ethnicity, and treatment arc extent.

RESULTS

There was no indication that higher (or lower) energy used in the treatment leads to greater (or less) IOP reduction. Similar results were obtained regarding the level of trabecular meshwork pigmentation. Race was not found to be associated with altered dose response in SLT. There were indications that treating the full 360 degrees, as opposed to smaller arcs, could be beneficial for more IOP reduction. IOP reduction from SLT was found to be similar to that provided by topical medications.

CONCLUSIONS

The optimal energy level of SLT needed for IOP reduction has not yet been definitively established, with all reported pulse energies resulting in similar IOP reduction. Furthermore, similar lack of conclusive findings exists regarding optimal SLT energy dosage for use in different races and degrees of trabecular meshwork pigmentation. This parameter and each of the abovementioned factors requires further research.

Selective laser trabeculoplasty for steroid-induced ocular hypertension following endothelial keratoplasty

Purpose: To examine the safety and efficacy of selective laser trabeculoplasty (SLT) in patients responding to topical steroids with elevated intraocular pressure following endothelial keratoplasty.Methods: Patients that underwent Descemet Membrane Endothelial Keratoplasty (DMEK) or Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) were offered SLT as first-line therapy if they presented with steroid response and met inclusion criteria. Patient demographics, best-corrected visual acuity (BCVA), steroid and glaucoma regimens were recorded before and after SLT.Results: Twelve eyes of 8 patients were recruited to the study. All patients demonstrated a reduction in IOP and only one patient remained on anti-glaucoma drops after SLT. The mean (±SD) reduction in IOP following SLT was 8.8 (±4.9) mmHg (p < 0.0001). BCVA remained stable and no adverse events following treatment were observed.Conclusions: SLT may be a safe and effective treatment option that reduces topical antihypertensive burden while allowing continuance of corticosteroids in steroid-responsive eyes at high risk of rejection following endothelial keratoplasty. Larger randomized studies are needed to compare SLT efficacy with topical medication in this patient group and to review any impact on graft survival and glaucoma progression.

Peripheral anterior synechiae after selective laser trabeculoplasty among Chinese patients

PURPOSE

Peripheral anterior synechiae (PAS) have been reported as a complication after argon laser trabeculoplasty, but rarely reported after selective laser trabeculoplasty (SLT). This study aims to determine the incidence and predictors of this potential complication in phakic eyes of Chinese patients.

METHODS

A retrospective review of consecutive Chinese phakic patients who underwent SLT for primary open-angle glaucoma or ocular hypertension from 2011 to 2015 was analyzed for post-operative outcomes, including the development of PAS.

RESULTS

There was a total of 292 patients (509 eyes) that were of Chinese ethnicity and eligible in our analysis. The 4-year incidence of PAS was 13.57% for the 221 eyes with documented gonioscopy after SLT, and the time, since first SLT, to PAS diagnosis was 5.62 years (2052 ± 75.2 days). After accounting for the inter-eye correlation by the mixed effect Cox regression model (AUC = 0.885), the predictors of earlier PAS diagnosis were baseline intraocular pressure (≥ 18 versus < 18) (HR = 4.6, p = 0.031), baseline use of bimatoprost (HR = 14.97, p = 0.006), and pre-existing hypertension (HR = 11.78, p = 0.016). There was no significant association of earlier PAS diagnosis with age (p = 0.434), baseline number of medications used (p = 0.693), and baseline use of brinzolamide (p = 0.326).

CONCLUSION

PAS development after SLT appears to be more common in Chinese patients, with a presumed 4-year incidence of 13.6%, based on retrospective review of eyes with subsequent documented gonioscopy findings.

TRIAL REGISTRATION

Hong Kong University Clinical Trials Registry (HKUCTR-2350).

Changes in peripapillary and macular vascular density after laser selective trabeculoplasty: an optical coherence tomography angiography study

OBJECTIVES

To determine the effect of laser trabeculoplasty on peripapillary retinal nerve fibre layer thickness (RNFL), fovea avascular zone (FAZ), peripapillary and macular vessel density (VD) in glaucoma using with optical coherence tomography angiography (OCT-A).

METHODS

This was a prospective observational study performed at the Glaucoma Research Centre, Montchoisi Clinic, Lausanne, Switzerland. Thirty-seven eyes with primary open-angle glaucoma from 21 patients were included. Optical coherence tomography angiography (OCT-A) scans were performed before laser trabeculoplasty and at 2 and 6 months after the procedure. AngioVue AngioAnalytic (Optovue Inc, Fremont, CA, USA) software was used to analyse the RNFL, FAZ, peripapillary and macular VD. Changes were analysed using mixed models, controlling for intraocular pressure (IOP) and signal strength index (SSI) variations.

RESULTS

Mean IOP decreased from 18.5 (±3.7) mmHg at baseline to 15.6 (±2.7) mmHg after 2 months (-15.3%; p < 0.001). No significant changes in RNFL thickness were noted following laser trabeculoplasty. Changes in peripapillary VD were mostly nonsignificant. Parafoveal (p = 0.001) and perifoveal VD (p = 0.025) significantly increased at 2 months, before reverting to near-baseline values at 6 months. No significant changes were observed in foveal parameters. Retinal nerve fibre layer thickness (RNFL) and VD changes were independent from IOP, but SSI had a significant influence on VD.

CONCLUSIONS

Following laser trabeculoplasty, peripapillary and macular VD temporarily increased before returning to near-baseline values by 6 months. No correlation was found between microvascular fluctuations and IOP, and no significant effect of laser trabeculoplasty on VD or RNFL was observed at 6 months despite persistent IOP reduction. Further research is warranted to understand its exact causes and clinical relevance.

Spotlight on MicroPulse Laser Trabeculoplasty in Open-Angle Glaucoma: What’s on? A Review of the Literature

Glaucoma is the most common cause of permanent blindness in the world, caused by a progressive optic neuropathy. Patients with glaucoma are often treated with topical medicines therapy in order to reduce intra-ocular pressure (IOP). On the other hand, laser therapies, with the introduction of Argon Laser Trabeculoplasty (ALT) and successively with Selective Laser Trabeculoplasty (SLT), were reported to be effective in IOP control, with low adverse effect rates. In recent years, the micropulse laser, a subthreshold laser technology, was introduced with the goal of reducing side effects while maintaining the effectiveness of the laser treatments. Several studies focused on Micropulse Diode Laser Trabeculoplasty (MDLT) in open-angle glaucoma, to evaluate its effectiveness and possible side effects. Promising results were reported, but irradiation circumstances have not been standardized yet and its role as a substitute for previous laser techniques has yet to be defined. As a result, the goal of this review was to analyze the physical principles at the basis of MDLT and to frame it in the open-angle glaucoma management setting, highlighting the advantages and shortfalls of this technique.

Burden of Trabeculectomy and Glaucoma Drainage Implantation after Laser Trabeculoplasty: A Two-Year Follow-up Study

PURPOSE

To evaluate the burden of incisional glaucoma surgery (trabeculectomy and glaucoma drainage device implantation) after laser trabeculoplasty (LTP) in the United States.

DESIGN

Retrospective, matched, case-comparison study.

PARTICIPANTS

Medicare beneficiaries who underwent LTP between January 2012 and December 2014 were identified using the 5% Medicare Current Beneficiary Survey.

METHODS

Subjects aged 35 years or older at the time of LTP with ocular hypertension, suspected glaucoma, or mild open-angle glaucoma (OAG) were matched to a comparison group without LTP on the basis of age, gender, race, geographic region, and glaucoma diagnosis codes. Survival analysis and Cox proportional hazard analysis were performed.

MAIN OUTCOME MEASURES

Primary analysis included risk of incisional glaucoma surgery. Secondary analysis included risk of conversion to moderate or severe OAG based on billing data.

RESULTS

The mean age of study participants was 75.0 ± 8.9 years. After 2 years, 40 of 2435 eyes required incisional glaucoma surgery after LTP, and 51 of 2435 eyes required glaucoma surgery in the comparison group (P = 0.27, adjusted for covariates). Regardless of intervention, Black Americans were more likely to require glaucoma surgery (hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.13-3.17). Patients with a diagnosis of OAG were more likely to require surgery than glaucoma suspects (HR, 2.03; 95% CI, 1.12-3.69). Black Americans were also more likely to require surgery or convert to more severe glaucoma (HR, 3.21; 95% CI, 1.92-5.37) versus White Americans.

CONCLUSIONS

Laser trabeculoplasty did not alter the need for subsequent incisional glaucoma surgery among glaucoma suspects or patients with mild OAG. Regardless of treatment with LTP, African heritage and OAG diagnosis status were risk factors for requiring glaucoma surgery.

Impact of Short-Term Topical Steroid Therapy on Selective Laser Trabeculoplasty Efficacy

Background: To evaluate whether short-term use of topical steroid therapy affected the efficacy of selective laser trabeculoplasty (SLT) for primary open-glaucoma (POAG). Methods: 25 eyes of 25 patients, who used a drop of dexamethasone 0.1% 4 times a day for 7 days as post-laser therapy, formed the Steroid SLT group and 24 eyes of 24 patients, where no topical steroids or nonsteroidal anti-inflammatory agents as post-laser therapy were used, formed the No-steroid SLT group. Success was defined as an intraocular pressure (IOP) lowering exceeding 20% of pretreatment IOP. Results: The mean follow-up time was 21.24 months for the Steroid SLT group and 20.25 months for the No-steroid SLT group (p = 0.990). No significant difference was found between the two groups for mean pretreatment IOP (22.20 mmHg vs. 22.33 mmHg), and for mean IOP reductions during whole follow-up period. At all follow-up visits, the mean IOP reductions were smaller in the Steroid SLT group than in the No-steroid SLT group. At all follow-up visits, the mean percent IOP reduction was smaller in the Steroid SLT group than in the No-steroid SLT group, and such a difference was significant at 12 months (25.4% vs. 29.6%, p = 0.047) and 24 months (25.3% vs. 29.7%, p = 0.024). According to the Kaplan–Meier survival analysis, the 24-month success rate was 84% in the Steroid SLT group and 79.2% in the No-steroid SLT group, with no differences between the groups (p = 0.675). Conclusion: Short-term use of topical steroid therapy had no impact on the efficacy of SLT for POAG.

Laser Trabeculoplasty for Open-Angle Glaucoma: A Systematic Review and Network Meta-Analysis

PURPOSE

We sought to comprehensively evaluate the effectiveness of different types of laser trabeculoplasty (LT) in the treatment of open-angle glaucoma.

DESIGN

Systematic review and network meta-analysis.

METHODS

Eligible randomized controlled trials were identified by searching PubMed, EMBASE, Cochrane Library, SCOPUS, China National Knowledge Infrastructure, and the Chinese Biomedical Literature Service System for studies published between January 1, 2000 and April 20, 2020. Eight interventions were evaluated, including argon LT (ALT), medications, 180-degree selective LT (SLT), 270-degree SLT, 360-degree SLT, new LT, transscleral 360-degree SLT with SLT performed without gonioscopy, and low-energy 360-degree SLT. The primary outcome was reduction of medicated and unmedicated intraocular pressure (IOP) at 6 months. Secondary outcomes included reduction of IOP at 12 months, incidences of complications, and change in number of medications. Head-to-head meta-analysis and network meta-analysis were performed using Stata and R software.

RESULTS

In total, 22 studies were included, involving 2859 eyes of 2704 patients. In terms of IOP reduction at 6 and 12 months, there were no statistically significant differences in both medicated and unmedicated IOP between any pairs of interventions considered herein, as determined based on both head-to-head and network meta-analyses (all P > .05). In terms of reduction of medications, the individuals treated with 180-degree SLT required fewer medications than those treated with ALT at 12 months (0.28 [95% confidence interval, 0.06-0.50]; P = .014). No severe adverse outcomes were reported for any of the interventions.

CONCLUSIONS

All the available types of LT are equally effective for decreasing IOP compared with medication-based therapy. The 180-degree SLT was slightly more effective than ALT in terms of reducing the number of medications needed. Additional well-performed randomized controlled trials with larger sample sizes are needed.

Selective laser trabeculoplasty lowered the untreated fellow eye long-term intraocular pressure: a 3-year observational study

To explore the long-term intraocular pressure (IOP)-lowering effect of monocular selective laser trabeculoplasty (SLT) in the untreated fellow eyes of open-angle glaucoma (OAG) patients. This was a retrospective observational study. Consecutive Chinese OAG patients who received monocular SLT treatment were included in this study. One hundred and eighty degree SLT was conducted as adjunctive treatment when anti-glaucoma medication was not sufficiently effective after clinical evaluation. Treatment success was defined as more than 20% IOP reduction of the baseline IOP levels. IOP-decreasing amplitude and SLT success rate of both eyes were investigated during the 3-year follow-up period. Age, gender, baseline IOP levels, number of medications, and SLT energy parameters were analyzed to determine its influence on IOP reduction effect and treatment success rate. A total of 32 Chinese OAG patients were included in this study and 25 of them completed the 3-year follow-ups. Their pretreatment IOPs were 18.85 ± 2.81 mmHg in the treated eyes and 17.38 ± 2.37 mmHg in the fellow eyes. At the 3-year follow-up visits, IOP decreased to 2.76 ± 3.72 mmHg (14.16%) in the treated eyes and 2.16 ± 2.73 mmHg (11.95%) in the fellow eyes, with a success rate of 47.83% (11 in 23 cases) and 44.00% (11 in 25 cases), respectively. IOPs of both eyes decreased significantly after SLT from 6 months and lasted to 3 years after treatment. Baseline IOP level was positively correlated with IOP reduction in the treated eyes and other factors were not correlated with IOP reduction and treatment success. Monocular SLT treatment as adjunctive treatment could lower IOPs not only in the treated eyes but also in the untreated eyes in poor medication-controlled OAG patients. In addition, its IOP reduction effect could last to 3 years after treatment in clinical practice.

Selective Laser Trabeculoplasty in the Treatment of Ocular Hypertension and Open-Angle Glaucoma: Clinical Review

Selective laser trabeculoplasty (SLT) is a glaucoma treatment that reduces intraocular pressure (IOP). Its mechanism is based on the biological effects of the selective application of laser energy to pigmented trabecular meshwork (TM) cells, resulting in increased outflow facility. Herein, we review current publications on SLT and summarize its efficacy and safety for different indications in open-angle glaucoma (OAG) and ocular hypertension (OHT) treatment. SLT effectively reduces IOP when used as a primary treatment. In patients whose IOP is medically controlled, SLT helps to reduce medication use, and when maximally tolerated topical therapy is ineffective, SLT facilitates the realization of the target IOP. SLT is a repeatable procedure for which the vast majority of complications are mild and self-limiting. With effective IOP reduction, low complication rates and the potential to repeat the procedure, SLT offers the possibility of delaying the introduction of medical therapy and other more invasive treatment modalities while simultaneously avoiding the accompanying complications. With this knowledge, we suggest that SLT be considered as an essential primary treatment option in OAG and OHT, switching to other treatment modalities only when laser procedures are insufficient for achieving the required target IOP.

Low-energy Selective Laser Trabeculoplasty Repeated Annually: Rationale for the COAST Trial

The recent Laser in Glaucoma and Ocular Hypertension Trial provided the evidentiary basis for a paradigm shift away from the historical medication-first approach to glaucoma--which has numerous limitations, the most important of which is poor adherence to therapy --and toward a laser-first approach. Now 20 years after its commercialization, selective laser trabeculoplasty (SLT) is routinely performed consistently with its initial description, with energy titrated to the appearance of fine, champagne-like cavitation bubbles. A recent data set suggested that lower energy SLT, applied as primary therapy and repeated annually irrespective of intraocular pressure--rather than pro re nata when its effect wanes and irrespective of intraocular pressure rises --yields longer medication-free survival than standard energy SLT repeated pro re nata. A new study--Clarifying the Optimal Application of SLT Therapy --has been initiated to explore this preliminary finding in a pair of consecutive randomized trials. Herein, we provide an evidence-based rationale for the use of low-energy SLT repeated annually as primary therapy for mild to moderate primary open-angle glaucoma or high-risk ocular hypertension.

Selective Laser Trabeculoplasty Versus MIGS: Forgotten Art or First-Step Procedure in Selected Patients with Open-Angle Glaucoma

Introduction

To evaluate the long-term effect on intraocular pressure (IOP) and glaucoma medication of selective laser trabeculoplasty (SLT) compared to minimally invasive glaucoma surgery (MIGS) in primary open-angle glaucoma (POAG) and its potential in clinical practice.

Methods

A total of 342 consecutive patients (stand-alone procedures) were included. One hundred and five patients underwent SLT treatment (360° SLT, 95–105 spots, Trabeculas SLT ARCLaser, Nürnberg, DE), 107 patients had an ab interno-derived trabeculotomy (Trabectome^®, NeoMedix, Tustin, USA), and 130 patients received iStent inject^® implantation (2 implants-Glaukos, CA, USA). IOP and glaucoma therapy were evaluated preoperatively, 1 day, 6 weeks, 3 months, 6 months, and 1, 2, and 3 years postoperatively. Statistical analysis was performed using a regression model and propensity matching score (reduced cohort number) using SPSS v20.0. Kaplan–Meier analysis was included using the following six criteria: criterion A (IOP ≤ 21 mmHg with or without medication, qualified success), criterion B (IOP ≤ 18 mmHg with or without medication, qualified success), criterion C (IOP ≤ 21 mmHg without medication, complete success), criterion D (IOP ≤ 18 mmHg without medication, complete success), criterion E (IOP ≤ 21 mmHg and IOP reduction > 20% after therapy), and criterion F (IOP ≤ 18 mmHg and IOP reduction > 20% after therapy).

Results

In the matched cohort, the SLT cohort showed an IOP reduction of 31.2% from 19.9 ± 2.3 to 13.7 ± 2.7 mmHg (p < 0.001) 3 years postoperatively; in Trabectome^® IOP decreased by 31.4% from 20.5 ± 1.3 to 13.8 ± 2.0 mmHg (p < 0.001) and in iStent inject^® by 29.9% from 19.5 ± 2.0 to 13.8 ± 2.7 mmHg (p < 0.001). Trabectome^® and iStent inject^® could not demonstrate a significant reduction in glaucoma therapy (Trabectome^®p = 0.138, iStent inject^®p = 0.612); a significant drop was noted in SLT (2.2 ± 1.2 to 1.7 ± 1.2, p = 0.046). SLT and MIGS achieved good to moderate survival rates using criterion A (93.3% SLT, 79.7% Trabectome^®, 77.6% iStent inject^®) and criterion B (74.5% SLT, 48.0% Trabectome^®, 56.2% iStent inject^®). As expected, low survival rates were obtained with non-filtering procedures: criterion C 11.1% in SLT, 6.5% in Trabectome^®, 7.0% in iStent inject^® and criterion D 3.0% in SLT, 4.3% in Trabectome^®, 3.7% in iStent inject^® in 3-year follow-up.

Conclusion

The SLT is a low-complication and effective method for reducing pressure in mild to moderate POAG. SLT is suitable as an initial procedure when setting up a step scheme; MIGS is the treatment of choice as a follow-up for mild to moderate forms of glaucoma and accepted topical therapy. Ethic approval had been given by the Ethikkommission Charité – Universitätsmedizin Berlin, EA4/047/20—retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-021-00347-0.

Outcome After Selective Laser Trabeculoplasty for Glaucoma Treatment in a Thai Population

Purpose

The study aimed to evaluate the efficacy and predictive factors of success after selective laser trabeculoplasty (SLT) for treating various types of open-angle glaucoma in a Thai population.

Design

The study employed a retrospective cohort design.

Materials and Methods

The study retrospectively recruited Thai subjects diagnosed with open-angle glaucoma receiving first time selective laser trabeculoplasty. Primary open-angle glaucoma (POAG), ocular hypertension (OHT) and other types of open-angle glaucoma were included. Reduced intraocular pressure (IOP) of 20% or decreased number of antiglaucoma drugs usage after SLT was defined as success. Various parameters were analyzed for association with SLT success.

Results

Ninety-six eyes were recruited in the study. Mean pre- and postSLT IOP were 19.31±3.59 and 15.04±3.13 mmHg, respectively. IOP decreased significantly in all follow-up visits (p<0.001). Overall, 59.4% met the treatment endpoint. More than 10% postSLT IOP elevation at 1 hour was the only covariate positively associated with SLT success in both univariate (odds ratio (OR) = 1.042, p = 0.037) and multivariate analyses (OR = 1.040, p = 0.046). Underlying hypertension and preSLT IOP were negatively associated with SLT success in both univariate (OR = 0.970, p = 0.026, OR = 0.955, p < 0.001) and multivariate analysis (OR = 0.970, p = 0.026, OR = 0.991, p < 0.001).

Conclusion

IOP significantly decreased as well as the number of antiglaucoma drugs needed after SLT. More than 10% postSLT IOP elevation at 1 hour was a positive predictor whereas systemic hypertension and preSLT IOP were negative predictors of SLT success.

Factors Associated With Favorable Laser Trabeculoplasty Response: IRIS Registry Analysis

PURPOSE

We examined patients in a large clinical registry to assess factors associated with laser trabeculoplasty (LTP) responses.

DESIGN

Retrospective cohort study.

METHODS

StudyPopulation: LTP patients in the Intelligent Research in Sight (IRIS) Registry, 2013-2018.

OBSERVATION

IRIS Registry data were extracted if the eye had a procedural code for LTP and a glaucoma diagnosis. Eyes were excluded if LTP laterality or baseline intraocular pressure (IOP) could not be determined. Following LTP, "nonresponders" were those with <20% IOP reduction after 8 weeks, while "responders" were those with ≥20% IOP reduction. MainOutcomeMeasures: Proportion of responders, odds ratios (OR) of pre-LTP factors associated with being a nonresponder.

RESULTS

A total of 263,480 eyes were included, with mean age 71.4 ± 11.7 years. Mean baseline IOP was 19.1 ± 5.0 mm Hg, mean number of pre-LTP medications was 2.1 ± 1.5. Response rate was 36.9% overall and 68.8% for those with baseline IOP >24 mm Hg. Higher baseline IOP was associated with reduced odds of nonresponse (OR = 0.60, P < .0001 for a 3 mm Hg increase). Angle recession, uveitis, and aphakia increased the odds of a nonresponse (ORs 2.46, 1.50 (both P < .0001), and 1.55 (P = .0259), respectively). In nonresponders with at least 1 medication at baseline, 76.3% of eyes had fewer medications postoperatively.

CONCLUSIONS

Lower baseline IOP, angle recession, uveitis, and aphakia were associated with increased odds of nonresponse. Future studies that analyze LTP responder survival and implementation lag would facilitate resource optimization in glaucoma therapy.

10-year outcomes of first-line selective laser trabeculoplasty (SLT) for primary open-angle glaucoma (POAG)

BACKGROUND

To evaluate long-term efficacy of selective laser trabeculoplasty (SLT) in treatment-naive early primary open-angle glaucoma (POAG) eyes.

METHODS

Retrospective study, 108 treatment-naïve eyes of 54 early POAG patients followed up for a mean (± standard deviation (SD)) of 83(27) months. Eyes treated with 360° SLT. Energy levels ranged from 0.6 to 1.4 mJ per pulse. Success of treatment defined as achieving at least 20% reduction of intraocular pressure (IOP) and IOP <19 mmHg.

MAIN OUTCOME MEASURE

proportion of eyes achieving success.

SECONDARY OUTCOME MEASURES

average time to re-treatment and change in visual field mean deviation (MD) over the follow-up period.

RESULTS

Baseline IOP (±SD) was 22.2 (± 4.9). Baseline MD (±SD) of standard automated perimetry was - 1.28 (± 2.36). Decrease in IOP was 6.5 (±3.6) mmHg at 1 year (n=108), 5.2 (±4.6) mmHg at 5 years (n=84) and 3.8 (±2.7) mmHg at 10 years (n=18). Treatment success rate 98% at year 1, 89% at year 5 and 72% at year 10. Failure most common after the third year. Median time to re-treatment 81 months (CI 60-100 months), with 60% needing re-treatment by 10 years. Higher baseline IOP associated with an increased risk of re-treatment. Treatment changed to drops in 4 eyes, but no cases needed glaucoma surgery. Change in visual field MD for the whole group averaged - 0.2 dB per annum.

CONCLUSIONS

Treatment of early POAG with first-line SLT, with re-treatments as required, is an effective strategy lasting a period of several years. 60% required re-treatments in the long-term with effective control of IOP and visual field loss remaining at an early stage. The potential for economic benefits in avoiding medications, and simultaneously improving quality of life in these cases is substantial.

Intraocular pressure-lowering effects of ripasudil, a rho-kinase inhibitor, and selective laser trabeculoplasty as adjuvant therapy in patients with uncontrolled glaucoma

OBJECTIVES

To compare the intraocular pressure (IOP)-lowering effects of ripasudil, a rho-kinase inhibitor, and selective laser trabeculoplasty (SLT) as adjuvant therapy in Japanese glaucoma patients and to identify the factors associated with treatment success.

METHODS

We performed a retrospective medical chart review of patients with glaucoma who received ripasudil or SLT as an adjuvant therapy. We collected data on 65 eyes (65 patients) with primary open-angle glaucoma, normal-tension glaucoma, or exfoliation glaucoma with at least 12 months of follow-up. IOP and number of glaucoma medications at 0, 1, 3, 6, 9, and 12 months were compared between and within groups. A repeated-measures mixed model was used to perform statistical analysis. We also investigated factors associated with treatment success, which was defined as ≥ 20% reduction in IOP at all follow-up periods, using univariate and multivariate logistic regression analysis.

RESULTS

Significant IOP reduction was observed at all time-points after treatment in the ripasudil group (n = 33) and in the SLT group (n = 32), with no statistically significant difference between the groups before or after treatment. Patients in the SLT group used more anti-glaucoma medications before treatment, but fewer during follow-up, than those in the ripasudil group. Regardless of treatment, higher baseline IOP was associated with treatment success [crude odds ratio: 1.21 (95% confidence interval: 1.06-1.38), adjusted odds ratio: 1.37 (95% confidence interval: 1.06-1.77)].

CONCLUSIONS

Adjuvant SLT or ripasudil in patients with inadequately controlled glaucoma both reduced IOP to a similar degree, but SLT contributed to reducing the number of medications used.

Visual Field Outcomes from the Multicenter, Randomized Controlled Laser in Glaucoma and Ocular Hypertension Trial (LiGHT)

PURPOSE

To compare visual field outcomes of ocular hypertensive and glaucoma patients treated first with medical therapy with those treated first with selective laser trabeculoplasty (SLT).

DESIGN

Secondary analysis of patients from the Laser in Glaucoma and Ocular Hypertension study, a multicenter randomized controlled trial.

PARTICIPANTS

Three hundred forty-four patients (588 eyes) treated first with medical therapy and 344 patients (590 eyes) treated first with SLT.

METHODS

Visual fields (VFs) were measured using standard automated perimetry and arranged in series (median length and duration, 9 VFs over 48 months). Hierarchical linear models were used to estimate pointwise VF progression rates, which were then averaged to produce a global progression estimate for each eye. Proportions of points and patients in each treatment group with fast (<-1 dB/year) or moderate (<-0.5 dB/year) progression were compared using log-binomial regression.

MAIN OUTCOME MEASURES

Pointwise and global progression rates of total deviation (TD) and pattern deviation (PD).

RESULTS

A greater proportion of eyes underwent moderate or fast TD progression in the medical therapy group compared with the SLT group (26.2% vs. 16.9%; risk ratio [RR], 1.55; 95% confidence interval [CI], 1.23-1.93; P < 0.001). A similar pattern was observed for pointwise rates (medical therapy, 26.1% vs. SLT, 19.0%; RR, 1.37; 95% CI, 1.33-1.42; P < 0.001). A greater proportion of pointwise PD rates were categorized as moderate or fast in the medical therapy group (medical therapy, 11.5% vs. SLT, 8.3%; RR, 1.39; 95% CI, 1.32-1.46; P < 0.001). No statistical difference was found in the proportion of eyes that underwent moderate or fast PD progression (medical therapy, 9.9% vs. SLT, 7.1%; RR, 1.39; 95% CI, 0.95, 2.03; P = 0.0928).

CONCLUSIONS

A slightly larger proportion of ocular hypertensive and glaucoma patients treated first with medical therapy underwent rapid VF progression compared with those treated first with SLT.

Selective laser trabeculoplasty versus drops for newly diagnosed ocular hypertension and glaucoma: the LiGHT RCT

BACKGROUND

Newly diagnosed open-angle glaucoma (OAG) and ocular hypertension (OHT) are habitually treated with intraocular pressure (IOP)-lowering eyedrops. Selective laser trabeculoplasty (SLT) is a safe alternative to drops and is rarely used as first-line treatment.

OBJECTIVES

To compare health-related quality of life (HRQoL) in newly diagnosed, treatment-naive patients with OAG or OHT, treated with two treatment pathways: topical IOP-lowering medication from the outset (Medicine-1st) or primary SLT followed by topical medications as required (Laser-1st). We also compared the clinical effectiveness and cost-effectiveness of the two pathways.

DESIGN

A 36-month pragmatic, unmasked, multicentre randomised controlled trial.

SETTINGS

Six collaborating specialist glaucoma clinics across the UK.

PARTICIPANTS

Newly diagnosed patients with OAG or OHT in one or both eyes who were aged ≥ 18 years and able to provide informed consent and read and understand English. Patients needed to qualify for treatment, be able to perform a reliable visual field (VF) test and have visual acuity of at least 6 out of 36 in the study eye. Patients with VF loss mean deviation worse than -12 dB in the better eye or -15 dB in the worse eye were excluded. Patients were also excluded if they had congenital, early childhood or secondary glaucoma or ocular comorbidities; if they had any previous ocular surgery except phacoemulsification, at least 1 year prior to recruitment or any active treatment for ophthalmic conditions; if they were pregnant; or if they were unable to use topical medical therapy or had contraindications to SLT.

INTERVENTIONS

SLT according to a predefined protocol compared with IOP-lowering eyedrops, as per national guidelines.

MAIN OUTCOME MEASURES

The primary outcome was HRQoL at 3 years [as measured using the EuroQol-5 Dimensions, five-level version (EQ-5D-5L) questionnaire]. Secondary outcomes were cost and cost-effectiveness, disease-specific HRQoL, clinical effectiveness and safety.

RESULTS

Of the 718 patients enrolled, 356 were randomised to Laser-1st (initial SLT followed by routine medical treatment) and 362 to Medicine-1st (routine medical treatment only). A total of 652 (91%) patients returned the primary outcome questionnaire at 36 months. The EQ-5D-5L score was not significantly different between the two arms [adjusted mean difference (Laser-1st - Medicine-1st) 0.01, 95% confidence interval (CI) -0.01 to 0.03; p = 0.23] at 36 months. Over 36 months, the proportion of visits at which IOP was within the target range was higher in the Laser-1st arm (93.0%, 95% CI 91.9% to 94.0%) than in the Medicine-1st arm (91.3%, 95% CI 89.9% to 92.5%), with IOP-lowering glaucoma surgery required in 0 and 11 patients, respectively. There was a 97% probability of Laser-1st being more cost-effective than Medicine-1st for the NHS, at a willingness to pay for a quality-adjusted life-year of £20,000, with a reduction in ophthalmology costs of £458 per patient (95% of bootstrap iterations between -£585 and -£345).

LIMITATION

An unmasked design, although a limitation, was essential to capture any treatment effects on patients' perception. The EQ-5D-5L questionnaire is a generic tool used in multiple settings and may not have been the most sensitive tool to investigate HRQoL.

CONCLUSIONS

Compared with medication, SLT provided a stable, drop-free IOP control to 74.2% of patients for at least 3 years, with a reduced need for surgery, lower cost and comparable HRQoL. Based on the evidence, SLT seems to be the most cost-effective first-line treatment option for OAG and OHT, also providing better clinical outcomes.

FUTURE WORK

Longitudinal research into the clinical efficacy of SLT as a first-line treatment will specify the long-term differences of disease progression, treatment intensity and ocular surgery rates between the two pathways.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN32038223.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 31. See the NIHR Journals Library website for further project information.

Short-Term Efficacy of Selective Laser Trabeculoplasty in Omani Eyes with Glaucoma: A Single Institutional Study

Purpose

There is some evidence suggesting a different nature of response to selective laser trabeculoplasty (SLT) among different races. Therefore, we aimed to assess the short-term efficacy, safety and nature of outcome of SLT in Omani eyes.

Patients and Methods

A retrospective review was performed of patients with open-angle glaucoma (OAG) or ocular hypertension (OHTN) who underwent a single session of 360-degree SLT between January 1, 2017 and December 31, 2018. The main outcome was mean IOP reduction and attainment of treatment success at 5 weeks and 12 weeks post treatment defined as at least 20% IOP reduction from baseline without further medications or interventions. Secondary outcomes were frequency of adverse events and factors predicting success.

Results

A total of 33 eyes of 33 Omani patients who underwent treatment with SLT were analyzed. The nature of response to laser followed a gradual pattern as the mean IOP reduction from baseline was 20.2% (5.21 mm Hg, P <0.001) at 5 weeks and further enhanced to 27.2% (6.95 mm Hg, P <0.001) at 12 weeks. Short-term success was achieved in 51.5% and 72.2% of eyes at 5 and 12 weeks, respectively. SLT was most effective in OHTN subgroup and those with higher baseline IOP (both P <0.001). Side effects were an infrequent occurrence, minor and transient.

Conclusion

The short-term success of SLT in Omani eyes was clinically relevant and comparable to the gradual pattern seen in patients of Indian ancestry. It is a safe therapeutic option in selective Omani eyes.

Laser Trabeculoplasty Perceptions and Practice Patterns of Canadian Ophthalmologists

Aim

To describe the current practice patterns and perceptions of Canadian ophthalmologists using laser trabeculoplasty (LTP).

Materials and methods

A cross-sectional survey of 124 members of the Canadian Ophthalmological Society (COS) who perform LTP was conducted. Descriptive statistics and Chi-square comparative analyses were performed on anonymous self-reported survey data.

Results

Of the 124 respondents, 34 (27.4%) completed a glaucoma fellowship. Use of selective laser trabeculoplasty (SLT) (94.4%) was preferred over argon laser trabeculoplasty (ALT) (5.6%). The most frequently cited reasons for SLT preference was less damage to trabecular meshwork (30.7%), availability (16.2%), and repeatability (16.2%). In all, 47.6% of the respondents performed LTP concurrently with medical treatment, 33.9% used it after medical treatment, and 17.7% used it as first-line treatment. Majority (87.1%) of the respondents believed that SLT is effective when repeated. In suitable patients, 41.9% of the respondents stated on average they repeat SLT once, 26.6% twice, and 19.4% greater than 2 times, respectively. Of those who repeat SLT on patients, 80.7% found repeat SLT treatments have good outcomes for patients. In all, 105 (84.7%) ophthalmologists responded they would benefit from an LTP practice guideline. Significantly more ophthalmologists without glaucoma fellowships perceived they would benefit from a practice guideline (p value <0.001).

Conclusion

This survey provides valuable practical information on how LTP is used in the treatment of glaucoma in Canada.

Clinical significance

The findings may serve as a baseline survey to trend future practices.

How to cite this article

Lee EY, Farrokhyar F, Sogbesan E. Laser Trabeculoplasty Perceptions and Practice Patterns of Canadian Ophthalmologists. J Curr Glaucoma Pract 2020;14(3):81–86.

Evaluation of selective laser trabeculoplasty as an intraocular pressure lowering option

PURPOSE

Selective laser trabeculoplasty (SLT) is one of the many treatment options for lowering intraocular pressure (IOP) in patients with glaucoma. This study aimed to evaluate the effect of SLT.

METHODS

Data were collected from medical records of 289 patients who underwent SLT treatment (180° of trabecular meshwork) during 2014 and 2015 at the Department of Ophthalmology, Sahlgrenska University Hospital, Mölndal, Sweden. Baseline characteristics and information from a follow-up within 100 days were also recorded. The study analysed different subtypes of glaucoma with regard to SLT, with a particular focus on exfoliative glaucoma, a common subtype in Sweden. Successful treatment was defined as an IOP lowering effect of >20% with no further changes in treatment. The impact of surgeon's experience on treatment outcome was also analysed.

RESULTS

Both patients with exfoliative glaucoma and those with primary open-angle glaucoma showed a reduction in mean IOP; no significant difference was found between these two subtypes before treatment or at the first follow-up. The success rate at follow-up (within 100 days) was 52%. There was a significant difference in outcome between surgeons with different levels of experience, but this difference could likely be explained by differences in treatment strategies and total energy used.

CONCLUSION

For many patients with glaucoma, SLT was an effective treatment option for lowering IOP. It was also effective for several glaucoma subtypes. However, not all patients had a significant reduction in IOP after treatment with SLT, and some may require additional treatment.

Selective laser trabeculoplasty versus topical medication as initial glaucoma treatment: the glaucoma initial treatment study randomised clinical trial

BACKGROUND/AIMS

To determine if selective laser trabeculoplasty (SLT) is superior to topical medication as a first-line treatment for glaucoma on quality of life (QoL) and clinical outcomes.

METHODS

In this international, longitudinal, multisite randomised controlled trial, treatment naïve mild-to-moderate primary open angle or exfoliation glaucoma patients were randomised 1:1 to SLT or topical medication. Glaucoma-specific QoL (primary outcome) was measured using the Glaucoma Outcomes Assessment Tool (GOAT; 342 items, 12 domains). Secondary outcomes included rate of successful intraocular pressure (IOP) reduction (>25% reduction from baseline) and presence of ocular surface disease including conjunctival hyperaemia and eyelid erythema. Our intention-to-treat analysis was performed at months 12 and 24.

RESULTS

Of 167 enrolled patients, 83 and 84 were randomised to SLT and topical medication, respectively; and 145 (n=75 SLT, n=70 medication) completed 24-month follow-up. While both treatment arms achieved significant within-group gains in GOAT outcomes at both endpoints, SLT patients reported a greater between-group improvement in 'social well-being' compared with medication patients (mean±SE=0.28±0.13; p=0.034) at 24 months. At month 24, the rate of successful IOP reduction was 18.6% (95% CI 3.0% to 34.3%, p=0.022) higher (absolute difference) in the medication compared with SLT group. More individuals in the medication group had conjunctival hyperaemia and eyelid erythema compared with SLT at 24 months.

CONCLUSION

Overall, we did not find evidence that SLT was superior to medication in improving glaucoma-specific QoL. While we found superior IOP reduction in the medication arm, eyelid erythema and conjunctival hyperaemia were more prevalent in these patients compared with the SLT group.

TRIAL REGISTRATION

ACTRN12611000720910.

SALT Trial: Steroids after Laser Trabeculoplasty: Impact of Short-Term Anti-inflammatory Treatment on Selective Laser Trabeculoplasty Efficacy

PURPOSE

This study examined whether short-term use of topical nonsteroidal anti-inflammatory drug (NSAID) or steroid therapy affected the efficacy of selective laser trabeculoplasty (SLT).

DESIGN

Double-masked, randomized, placebo-controlled, dual-center, multisurgeon trial.

PARTICIPANTS

Patients older than 18 years with intraocular pressure (IOP) of more than 18 mmHg for whom the clinician decided SLT was the appropriately indicated therapy were randomized to 1 of 3 groups in a ratio of 1:1:1 as follows: ketorolac 0.5%, prednisolone 1%, or saline tears.

METHODS

After SLT, patients randomized into each group were instructed to use an unmarked drop 4 times daily starting the day of SLT and continuing for 4 additional days. The Kruskal-Wallis test and Wilcoxon rank-sum test were used for continuous variables when comparing 2 or 3 treatment groups, respectively. The Fisher exact test was used for categorical variables.

MAIN OUTCOME MEASURES

The primary outcome of this study was IOP at 12 weeks. Secondary outcome measures included IOP at 1 and 6 weeks, patient-reported pain, and detectable anterior chamber inflammation.

RESULTS

Ninety-six eyes of 85 patients fit inclusion criteria and were enrolled between the 2 sites. The NSAID, steroid, and placebo groups were similar in baseline demographics and baseline IOP (mean, 23.3±3.9 mmHg; P = 0.57). There was no statistically significant difference in IOP decrease among groups at week 6. Both the NSAID and steroid groups showed a statistically significantly greater decrease in IOP at week 12 compared with the placebo group (mean, -6.2±3.1 mmHg, -5.2±2.7 mmHg, and -3±4.3 mmHg, respectively; P = 0.02 [analysis of variance] and P = 0.002 [t test] for NSAID vs. placebo groups; P = 0.02 for steroid vs. placebo groups).

CONCLUSIONS

Significantly better IOP reduction at 12 weeks was measured in eyes treated with steroid or NSAID drops after SLT. Short-term postoperative use of NSAID or steroid drops may improve IOP reduction after SLT. Longer-term follow-up studies are indicated.

Comparative study of the efficacy of selective laser trabeculoplasty as initial or adjunctive treatment for primary open-angle glaucoma

Aim:

The aim of this study is to compare the efficacy of selective laser trabeculoplasty as initial or adjunctive treatment for primary open-angle glaucoma in a retrospective chart review.

Methods:

28 eyes of 28 patients with newly diagnosed primary open-angle glaucoma, who formed the initial selective laser trabeculoplasty group, and 31 eyes of 31 patients suffering from medical uncontrolled primary open-angle glaucoma, who formed the adjunctive selective laser trabeculoplasty group, were treated with 180° selective laser trabeculoplasty. Patients were evaluated 1, 3, 6, 12, 18 and 24 months after treatment. Success was defined as an intraocular pressure lowering exceeding 20% of pretreatment intraocular pressure.

Results:

The mean follow-up time was 20.25 months (standard deviation = 8.1) for the initial selective laser trabeculoplasty group and 18.87 months (standard deviation = 8.8) for the adjunctive selective laser trabeculoplasty group (p = 0.538). No significant difference was found between the two groups for mean pretreatment intraocular pressure (21.43 mmHg (standard deviation = 3.2) vs 21.97 mmHg (standard deviation = 2.6); p = 0.766), for mean intraocular pressures and mean intraocular pressure reductions during whole follow-up period. At all follow-up visits, the mean percent intraocular pressure reduction was smaller in the adjunctive selective laser trabeculoplasty group than in the initial selective laser trabeculoplasty group, and such a difference was significant at 1 month (21.55% vs 26.79%; p = 0.039) and 24 months (24.82% vs 28.10%; p = 0.041). According to the Kaplan–Meier survival analysis, the 24-month success rate was 71.4% in the initial selective laser trabeculoplasty group and 71% in the adjunctive selective laser trabeculoplasty group, with no differences between the groups (p = 0.913).

Conclusion:

Selective laser trabeculoplasty is equally efficient in reducing intraocular pressure as initial or adjunctive treatment for primary open-angle glaucoma over 24 months.

Selective laser trabeculoplasty as replacement therapy in medically controlled glaucoma patients

PURPOSE

We examined selective laser trabeculoplasty (SLT) as a replacement therapy for medically controlled open-angle glaucoma (OAG) or ocular hypertensive patients.

METHODS

A prospective randomized interventional clinical trial on 143 glaucoma patients. Patients were randomized to either receiving SLT or to the control group that continued on pressure lowering medication. Data were recorded 1 hr, 1 week, 1, 3, 6, 12 and 18 months after SLT. Primary outcome was number of medications at 12 and 18 months while maintaining a predetermined target intraocular pressure (IOP).

RESULTS

Selective laser trabeculoplasty (SLT) reduced number of medications from a mean of 1.5 at baseline, to 0.35 after 12 months and 0.29 after 18 months. Meanwhile, SLT achieved more than 20% IOP lowering in 95% of eyes and more than 30% IOP lowering in 86% of eyes after 18 months. Seventy-seven per cent of our eyes no longer needed any medication after SLT at 18 months.

CONCLUSION

Selective laser trabeculoplasty (SLT) enabled a reduction in number of medications while maintaining good IOP control. Selective laser trabeculoplasty (SLT) was able to completely replace medical therapy in 77% of eyes after 18 months. Selective laser trabeculoplasty (SLT) as replacement therapy may reduce local and systemic side-effects and prevent adherence issues.

Efficacy of selective laser trabeculoplasty following incisional glaucoma surgery

AIM

To evaluate the efficacy of selective laser trabeculoplasty (SLT) in glaucomatous eyes with previous incisional glaucoma surgery.

METHODS

A retrospective cohort of eyes that underwent SLT at a single institution from 2013-2015 were followed for 1y. Reduction in intraocular pressure (IOP) following SLT was evaluated in eyes with prior trabeculectomy with ExPress mini shunt (Alcon, Ft Worth, TX, USA), Ahmed valve (New World Medical, Cucamonga, CA, USA), or combined phacoemulsification-trabeculectomy. A control group was included with eyes without prior surgery that underwent SLT. Success was defined as >20% drop in IOP from pre-SLT baseline.

RESULTS

One-hundred and six eyes were included with 53 in both the prior glaucoma surgery (PGS) and no prior glaucoma surgery (NPGS) groups. Mean pre-SLT IOP was 19.2±4.3 and 20.6±6.0 mm Hg for PGS and NPGS groups, respectively (P=0.17). Both groups produced statistically significant IOP reductions at 1 and 6mo (P<0.04). At 6mo, mean IOP reduction reached 7.3% and 10.8% for the PGS and NPGS groups, respectively (P=0.42). Overall, 27.9% and 31.7% of eyes in PGS and NPGS groups met success criteria at 1y (P=0.70). In the PGS group, eyes with baseline IOP ≥21 mm Hg had IOP reductions of 18.1% (P<0.001), 16.7% (P<0.01), and 8.4% (P=0.31) compared to eyes with baseline IOP <21 mm Hg who had IOP reductions of 2.3% (P=0.39), 3.4% (P=0.19), and 1.1% (P=0.72) at 1, 6mo, and 1y, respectively.

CONCLUSION

SLT is efficacious in eyes with prior incisional glaucoma surgery and results in similar IOP reductions compared to eyes without PGS. A larger IOP reduction is observed following SLT in eyes with higher pre-SLT IOP.

Selective laser trabeculoplasty: past, present, and future

Over the past two decades, selective laser trabeculoplasty (SLT) has increasingly become an established laser treatment used to lower intraocular pressure in open-angle glaucoma and ocular hypertensive patients. In this review we trace the origins of SLT from previous argon laser trabeculoplasty and review the current role it has in clinical practice. We outline future directions of SLT research and introduce emerging technologies that are further developing this intervention in the treatment paradigm of glaucoma.

Randomized Prospective Study of the Use of Anti-Inflammatory Drops After Selective Laser Trabeculoplasty

PURPOSE

Evaluating the use of Indomethacin, Dexamethasone, and no anti-inflammatory treatment immediately after selective laser trabeculoplasty (SLT).

MATERIALS AND METHODS

Prospective randomized clinical trial of 132 eyes. Both eyes of the patient underwent SLT. One of the eyes was treated with Indomethacin 0.1% or Dexamethasone 0.1% 3 times daily for 1 week; the other eye did not receive any anti-inflammatory treatment. Intraocular pressure (IOP) and inflammatory parameters were recorded at 1 hour, 1 week, 1, 3, and 6 months.

RESULTS

Cells in the anterior chamber were present in 57% to 71% of the patients after 1 hour. About 16% to 37% of the patients reported pain/discomfort after 1 hour. Redness was present before SLT in 29% to 34% of the patients, probably due to antiglaucoma medication. After 1 hour, the amount of redness recorded raised to 32% to 42%, but the amount of patients with redness returned to pretreatment levels after 1 week. An IOP peak of >5 mm Hg above baseline IOP 1 hour after laser was present in 3% to 9% of the patients. IOP lowered 11% to 21% compared with IOP at baseline. The number of medications needed changed from 1.45 to 1.49 before, to 0.23 to 0.45 six months after SLT.No differential effects based on the kind of anti-inflammatory treatment or no treatment were found for any of the parameters.

CONCLUSIONS

SLT induces little inflammation: anti-inflammatory drops do not make a significant difference in pain, redness, cells in anterior chamber, or peak IOP following SLT.The IOP-lowering effect of the SLT is not influenced by the use of Indomethacin or Dexamethasone.

Selective Laser Trabeculoplasty vs. Fixed Combinations with Timolol in Practice: A Replacement Study in Primary Open Angle Glaucoma

OBJECTIVES

To evaluate the potential of selective laser trabeculoplasty (SLT) in two arms (360˚ vs. 180˚) as a replacement for fixed combinations (FCs) with timolol in primary open angle glaucoma over 6 months.

MATERIALS AND METHODS

Of 40 patients in a prospective, comparative, interventional case series, 18 eyes and 22 eyes were randomized to SLT 180º and SLT 360º groups, respectively, along with 40 fellow-control eyes. FC with timolol was discontinued on the day of treatment for the eye to be operated on, while ongoing therapy was not interrupted for the contralateral eye. Eyes were examined for intraocular pressure (IOP) elevation 1 hour and 1 day after SLT. The follow-up visits were then scheduled for 1 week, 1 month, 3 months, and 6 months after, during the which the IOP of both eyes and any possible complications were evaluated.

RESULTS

There were no statistically significant differences in mean IOPs through 6 months among the groups with exception of postlaser 1 hour and postlaser 1 day (p<0.001 and p=0.010, respectively). Multiple comparison analysis showed significantly higher IOP in both SLT 180º and SLT 360º subgroups compared to their controls at postlaser 1 hour (p=0.007, p<0.001) but significantly lower IOP only in SLT 360º subgroup compared to the controls at postlaser day 1 (p=0.013).

CONCLUSION

SLT offers promising potential as a substitute equivalent to efficacy of FCs with timolol. However, SLT 360˚ may not achieve additional IOP reduction.

Quality of life in glaucoma patients after selective laser trabeculoplasty

AIM

To compare quality of life and treatment satisfaction between patients who had selective laser trabeculoplasty (SLT) and those on medication.

METHODS

A prospective clinical trial on 143 glaucoma patients that received SLT and a control group that continued using anti glaucoma medication was conducted. Tear break-up time (BUT), punctuate keratitis, need for help, use of artificial tears and the treatment satisfaction survey of intraocular pressure (IOP) were measured at baseline, 6 and 12mo.

RESULTS

SLT was able to reduce the mean number of medications needed from 1.56±0.81 to 0.42±0.66 at six months and to 0.33±0.69 at one year. Punctuate keratitis was observed significantly less often (12.24%) after SLT than before (35.94%; P=0.03). Use of artificial tears and BUT did not change significantly after SLT (P>0.05). At baseline, patients in the SLT group were significantly less convinced of medication effectiveness (P=0.006) and complained more about side effects (P=0.003). After SLT, these patients had significantly more confidence in their therapy (P<0.001), showed less side effects (P=0.006), complained less about changes in appearance of the eyes (P=0.003) and were less inconvenienced by the use of eye drops (P<0.001).

CONCLUSION

SLT is able to improve treatment-related quality of life in glaucoma patients.

Selective laser trabeculoplasty in pseudophakic and phakic eyes: a prospective study

AIM

To compare the efficacy of selective laser trabeculoplasty (SLT) in replacing medical therapy in pseudophakic and phakic eyes.

METHODS

Subgroup of a prospective randomized clinical trial including patients with primary open angle glaucoma or ocular hypertension controlled with medication. Of 38 pseudophakic eyes were matched with 38 phakic eyes. SLT was offered as a way to decrease medication while maintaining the same low eye pressure. SLT was performed over 360°, at 3ns, spotsize 400 µm, 100 spots. Data [intraocular pressure (IOP), number of medications needed] were measured at 1h, 1wk, 1, 3, 6 and 12mo. An independent-samples t-test was performed to compare baseline characteristics of the phakic and the pseudophakic group and differences in evolution of mean IOP and number of used medications. Chi-squared analysis was performed to investigate proportions of fast, slow and non-responders.

RESULTS

The mean IOP measurement was 13.00± 2.88 mm Hg in the phakic group (38 eyes) and 13.51±3.06 mm Hg in the pseudophakic group (38 eyes) (P>0.05). This changed little after SLT and IOP lowering effect was comparable between the two groups. Main aim however was to lower the amount of medication needed. In the phakic group medication lowered from 1.29±0.62 at baseline, to 0.15±0.46 after 12mo; a reduction of 88.37%. In the pseudophakic group, used medication changed from 1.71±1.04, to 0.41±0.61; a 76.02% reduction. The differences were not statistically significant at any time point (P>0.05). IOP lowering occurred slightly faster in the pseudophakic group (50% of patients after one week) than in the phakic group (68% of patients after more than 4wk). The difference was not significant (P>0.05).

CONCLUSION

IOP lowering effect of SLT is comparable between phakic and pseudophakic eyes.

Feasibility of laser trabeculoplasty in angle closure glaucoma: a review of favourable histopathological findings in narrow angles

Selective laser trabeculoplasty (SLT) has been indicated as a safe and efficient treatment for primary open-angle glaucoma; however, recent studies have also shown positive results with the use of SLT in some clinical conditions related to primary angle-closure glaucoma (PACG). Despite the potential benefits of SLT in selected cases of PACG, the mechanisms underlying the modifications in the trabecular meshwork tissue of patients with PACG are poorly understood. This narrative review approached both the current, limited knowledge about the histological changes observed in different forms of PACG and the clinical results of SLT treatment for PACG. Favourable outcomes of SLT in patients with PACG, specifically in areas of non-occluded angle, need further substantiation through large controlled clinical trials. A deeper understanding of the biomolecular changes of those areas is essential to improve both laser technical details and the clinical efficacy of SLT therapy.

Correlation of Intraocular Pressure Between Both Eyes After Bilateral Selective Laser Trabeculoplasty in Open-angle Glaucoma

PURPOSE

To investigate the correlation of intraocular pressure (IOP)-lowering effects of selective laser trabeculoplasty (SLT) between the 2 eyes treated with SLT in open-angle glaucoma (OAG).

METHODS

This prospective cohort study sequentially recruited subjects with bilateral OAG. All subjects received a single session of 360-degree SLT treatment. Success was defined as IOP reduction of ≥20%. Spearman correlation was used to compare the following parameters between the 2 eyes following SLT: IOP at day 1, 1 week, and 1 month; percentage of success; and IOP reduction.

RESULTS

In 84 eyes of 42 subjects that received bilateral SLT treatment, both eyes had statistically comparable baseline characteristics. There were significant correlations between the IOP in both eyes at all time intervals following SLT as well as for the percentage of IOP reduction and the success rate at 1 month after SLT (all r≥0.7, P<0.0001). A total of 42.9% of subjects had bilateral success and 38.1% had bilateral nonsuccess with a significant correlation between both eyes in these 2 groups (Spearman r>0.6, P<0.02). Nineteen percent had success in 1 eye and nonsuccess in the fellow eye with an inverse correlation between the 2 eyes (Spearman r=-0.7, P=0.03).

CONCLUSION

There is a strong and significant correlation in the IOP-lowering response to SLT between both eyes in near 80% of treated OAG subjects, whereas near 20% had an asymmetrical and inverse response to SLT between both the eyes.

Where does selective laser trabeculoplasty stand now? A review

Background

Chronic treatment of glaucoma can present a challenge in patients who lack the means and/or the discipline to use daily glaucoma medication. We wondered if selective laser trabeculoplasty (SLT) could be a useful alternative.

Methods

Inclusion criteria: controlled trials comparing efficacy of SLT in adult patients with any form of open angle glaucoma or ocular hypertension and case reports on side effects of SLT. Two recent meta-analyses identified eight randomized clinical trials (RCTs) comparing the effect of SLT with medication (prostaglandin analogs) and with argon laser trabeculoplasty (ALT). We took these eight RCTs as reference base and calculated their success rates where they were not given. Other articles were added to elaborate on technique and side effects.

Results

Mean intraocular pressure (IOP) reduction after SLT was 3.8–8.0 mmHg after 6 months to 1 year. Mean success rate of SLT at 6 months to 1 year is 55–82 %. Higher IOP before laser predicts a higher IOP-lowering effect. In terms of mean IOP reduction, reduction in number of medications and treatment success, the effect of SLT was found to show no clinically relevant difference from that of contemporary medication (prostaglandin analogs) and from ALT.

Conclusions

The evidence indicates that SLT is an efficacious primary or adjunctive therapy for treating glaucoma.

Selective laser trabeculoplasty in primary open-angle glaucoma: Primary versus secondary treatment outcomes

Objective: To compare the outcomes of selective laser trabeculoplasty (SLT) on treatmentnaive, primary open-angle glaucoma (POAG) patients with those of SLT on patients previously treated medically and/or surgically. Secondary objectives: To establish whether age, race or gender influenced SLT outcomes.Design: A retrospective chart review of patients who received SLT therapy for POAG between June 2011 and January 2015.Subjects: Group A: Treatment-naive patients (n = 15). Group B: Prior medical therapy and/or prior surgery (n = 69).Methods: Group A: Patients were treated with SLT therapy as first line, with medical treatment added as needed. Group B: Patients were treated with SLT therapy as additional therapy to medication and/or surgery. All patients were followed up for at least 1 year.Main outcome measures: A reduction in intraocular pressure (IOP) of at least 20% from baseline was considered significant.Results: The following percentage reduction in IOP was found in the different groups: Group A 50.7%, Group B 32.0%, Africans 52.2%, Indians 29.8% and Caucasians 28.87%.Conclusion: In our study patients, SLT achieved significant reductions in IOPs in treatmentnaive as well as previously surgically and medically treated eyes with POAG. Statistically significant higher reductions in IOP at 1 year after SLT was seen in treatment-naive eyes, patients older than 70 years when compared with younger patients, female patients (54%) when compared with male patients (30%) and in patients of African (52%) descent compared with Caucasians (30%).