Selective laser trabeculoplasty (SLT) complicated by intraocular pressure elevation in eyes with heavily pigmented trabecular meshworks

Effect of Preoperative Trabecular Meshwork Pigmentation and Other Eye Characteristics on Outcomes of Combined Phacoemulsification/Minimally Invasive Glaucoma Surgery

PURPOSE

To investigate associations between pigmentation of the trabecular meshwork (PTM) and other preoperative eye characteristics and outcomes of minimally invasive glaucoma surgery combined with phacoemulsification (Phaco/MIGS).

DESIGN

Retrospective interventional case series.

PARTICIPANTS

Academic glaucoma clinic patients with symptomatic cataract and glaucoma treated with combined Phaco/MIGS.

METHODS

Analyzing preoperative PTM, intraocular pressure (IOP), IOP-lowering medications and visual acuity (VA) data in relation to Phaco/MIGS outcomes.

MAIN OUTCOME MEASURES

Pigmentation of the trabecular meshwork and other preoperative eye characteristics in relation to Phaco/MIGS success defined as postoperative IOP between 5 and 21 mmHg and IOP reduction of ≥ 20% and/or a reduction of ≥ 1 IOP-medications compared to baseline, and final IOP, IOP-lowering medications and VA.

RESULTS

A total of 265 eyes (172 patients, mean age, 73.5 [standard deviation, 10.0], range 35-95 years, male 40.0%) were identified and categorized with high PTM (108 eyes, 40.8%) or low PTM (157 eyes, 59.2%). The high PTM group, compared with the low PTM group, demonstrated higher preoperative IOP (16.7 [standard error 0.4] vs. 15.2 [0.4] mmHg, P = 0.009), included more eyes with primary open-angle glaucoma (POAG, P = 0.03), fewer eyes with normal-tension glaucoma (NTG, P = 0.01), and fewer eyes with mild stage glaucoma (P = 0.001). Compared to baseline, final IOP decreased by 6.5 [2.4]% and 13.4 [3.0]% (P = 0.075) to 13.5 [0.3] mmHg and 13.6 [0.4] mmHg (P = 0.77) in the low and high PTM groups, respectively, and IOP-lowering medications decreased by 34.6 [4.9]% (n = 116) and 18.1 [7.3]% (n = 85), respectively (P = 0.062). Surgical success was 59.9% and 58.3%, respectively (P = 0.87). It was positively associated with higher preoperative IOP (hazard ratio 1.08 [95% confidence interval 1.04-1.12] P < 0.0001) and higher number of preoperative IOP-medications (1.20 [1.05-1.37] P = 0.007), negatively associated with history of selective laser trabeculoplasty (SLT, 0.40 [0.23-0.68] P = 0.0009) and longer axial length (0.87 [0.80-0.94], P = 0.0006), but was not associated with PTM.

CONCLUSIONS

Higher PTM was associated with POAG rather than NTG, with more severe glaucoma and higher preoperative IOP, but not with Phaco/MIGS success. Surgical success was positively associated with higher preoperative IOP and number of IOP-medications and negatively associated with history of SLT and longer axial length. These findings may help guide glaucoma surgeons in surgical planning and patient counseling.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Intraocular pressure profile following selective laser trabeculoplasty in pigmentary and primary open-angle glaucoma

PURPOSE

To compare the intraocular pressure (IOP) profile and the incidence of IOP spikes following selective laser trabeculoplasty (SLT) between pigmentary glaucoma (PG) and primary open-angle glaucoma (POAG).

MATERIALS AND METHODS

Retrospective comparative study of 65 PG eyes of 51 patients matched with 65 POAG eyes of 65 patients who received SLT. Matching was done based on age, gender, glaucoma severity, pre-laser IOP, and number of medications. Post-SLT IOP spike was defined as IOP elevation ≥5mmHg, 30-45 min after the laser.

RESULTS

In PG and POAG groups, the average age was 62.33 ± 9.18 and 62.58 ± 9.19 years (p = 0.95). The glaucoma severity (p = 0.708), baseline IOP (PG = 21.61 ± 1.34mmHg vs. POAG = 21.13 ± 5.09mmHg, p = 0.943), and number of topical glaucoma medications(PG = 2.34 ± 1.34 vs. POAG = 2.1 ± 1.41, p = 0.342) were comparable. More PG patients were on oral acetazolamide (PG = 26.15% vs. POAG = 1.5%, p < 0.001). Average logMAR visual acuity was significantly higher in the POAG group (0.207 ± 0.3 vs. 0.192 ± 0.37, p = 0.012). Eyes with PG received lower laser energy (POAG = 63.65 ± 22.03 mJ vs. PG = 43.71 ± 25.68 mJ, p < 0.001). IOP spikes were recorded in 5 PG eyes (7.6%) and none in the POAG group (p = 0.058). Failure rates were similar (PG = 50.7% and POAG = 43.1%, p = 0.205). In multivariable analysis, only pre-laser IOP (coefficient = 2.154 [CI: 0.765-3.543], p = 0.003) was a significant predictor of IOP change percentage after 12 months.

CONCLUSIONS

SLT was comparably effective in both PG and POAG. IOP spikes were observed only in the PG group, though the total laser energy was lower in this group compared with POAG.

Optimal Performance of Selective Laser Trabeculoplasty: Results from the Swedish Optimal SLT Multicenter Randomized Controlled Trial

PURPOSE

Selective laser trabeculoplasty (SLT) is a first-line treatment for glaucoma and ocular hypertension. However, due to insufficient comparative evidence in efficacy and safety, several SLT treatment protocols are currently used in practice. The objective of this trial was to compare the clinical outcomes of the 4 most significant SLT variants.

DESIGN

Prospective, multicenter, masked, randomized controlled trial (RCT).

PARTICIPANTS

Four hundred patients with glaucoma or ocular hypertension. The cohort consisted of both treatment-naive patients and patients undergoing glaucoma treatment, at different stages of disease.

METHODS

Selective laser trabeculoplasty was performed with 50 ± 5 laser spots in 180 degrees or with 100 ± 10 spots in 360 degrees. The laser power was titrated to either just below the cavitation bubble level ("standard energy") or to a level producing cavitation bubbles at 50% to 75% of laser applications ("high energy"). Thus, 4 different treatment protocols were included - 180/standard, 180/high, 360/standard, and 360/high. The study adhered as close as possible to regular clinical management, but within a scientific framework.

MAIN OUTCOME MEASURES

Reduction of intraocular pressure (IOP) 1 to 6 months after SLT. The proportion of patients achieving a 20% IOP reduction without any further intervention. Time to glaucoma treatment escalation in a Kaplan-Meier survival analysis.

RESULTS

SLT performed with the 360/high protocol was shown to be superior regarding all primary endpoints. The IOP reduction 1 to 6 months after SLT was 5.4 mmHg in the 360/high group, compared to 3.4, 3.2, and 4.2 mmHg with the 180/standard, 180/high, and 360/standard protocols, respectively (P < 0.001). Furthermore, the success rate after 6 months was significantly higher -58.3%, compared with 30.2%, 29.3%, and 41.7% (P < 0.001). The median time to glaucoma treatment escalation was more than twice as long with 360/high SLT -1323 days, compared to 437 days, 549 days, and 620 days (P < 0.001). Although postoperative discomfort was more frequent with the 360/high protocol, symptoms were generally mild and transient. Adverse events were rare in all groups.

CONCLUSIONS

The magnitude and longevity of SLT results increases substantially if SLT is performed according to the 360/high protocol, without compromising safety. Therefore, we recommend that 360/high SLT be considered as standard treatment.

FINANCIAL DISCLOSURES

The authors have no proprietary or commercial interest in any materials discussed in this article.

Selective laser trabeculoplasty: An updated narrative review

Selective laser trabeculoplasty (SLT) has experienced a resurgence in interest, primarily driven by promising findings from the Laser in Glaucoma and Ocular Hypertension Trial. By offering SLT as an initial drug-free treatment option, we may be able to thwart issues such as adherence and persistence that plague our current medical management protocols. In this comprehensive narrative review, we delve into the current body of literature that explores the utility of SLT across a wide spectrum of scenarios and glaucoma subtypes. We present evidence that provides valuable insight into the efficacy and benefits of SLT, positioning it as a viable option in the management of glaucoma. Careful consideration of the associated risks and challenges is also necessary for successful adoption into clinical practice. Despite the ample evidence supporting SLT's efficacy, some questions remain regarding its long-term effects and the potential need for retreatment. This review aims to shed light on these aspects to guide clinicians in making informed decisions and tailoring treatment plans to individual patient needs. This review also provides the readers with a bird's eye view of the potential impact of SLT and adds clarity to the various therapeutic protocols that one can follow to ensure optimal clinical outcomes for our patients.

Pigment dispersion syndrome and pigmentary glaucoma: overview and racial disparities

Pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG) are two stages within the same ophthalmic disease spectrum, which are known to be affected by race. The prevalence of PDS is underestimated, largely due to its minor clinical symptoms. Although the prevalence of PG is low, the visual impairment associated with PG is extremely severe. The prevalence of PDS-PG is four or more times higher in Caucasians than in Blacks or Asians, and the "classic" PDS in Caucasians has long been used as a benchmark diagnostic criterion. Following extensive research focused on African Americans and Asians, the standard for diagnosing PDS-PG was refined. At the same time, the pathogenesis of PDS is not the same in different races. Hence, the effectiveness of preventive treatment and the need for treatment may not be equivalent in different races. The rate of conversion of PDS to PG is nearly 1/3 in Caucasians and higher in blacks and Asians, requiring more aggressive treatment and monitoring. We systematically searched a PubMed database from inception to March 2022 to provide an overview of research progress in various aspects of PDS-PG. Specifically, this paper considers the effects of race on disease prevalence, clinical manifestation, diagnostic criteria, disease mechanism, hereditary traits, treatment, and prevention to provide an accurate and comprehensive guide for the diagnosis and treatment of PDS-PG in various races.

Selective laser trabeculoplasty is safe and effective in patients previously treated with prostaglandin analogs: An evidence-based review

PURPOSE

Prostaglandin analogs (PGAs) are first-line treatments for ocular hypertension (OHT) and open-angle glaucoma (OAG). However, frequent side effects and high costs hinder patient's compliance resulting in disease progression. Evidence suggests selective laser trabeculoplasty (SLT) may be considered a first-line treatment for OHT and OAG due to its safety profile, minor side effects, and reduced costs. Considering that PGAs and SLT share action mechanisms, it is hypothesized that previous PGA therapy may affect subsequent SLT efficacy. Therefore, we analyzed if PGAs reduce SLT efficacy.

METHODS

An evidence-based review was performed to assess the safety and efficacy of SLT in patients previously treated with PGAs. For this purpose, we performed an extensive literature search using the National Library of Medicine's PubMed and Google Scholar database for all English language articles published until May 2021.

RESULTS

There is evidence of non-superiority of PGAs therapy versus SLT for OHT and OAG. A multicenter, randomized, observer-masked clinical trial (RCT) of untreated OHT and OAG patients concluded that SLT should be offered as the first-line treatment for these patients. This study was supported by a meta-analysis of RCTs, comparing SLT efficacy versus antiglaucoma drugs only, with the advantage of an SLT lower rate of adverse effects.

CONCLUSIONS

Cost-effectiveness, patient compliance, and antiglaucoma drugs' side effects, including higher surgical failure, favor consideration of SLT as first-line therapy for OAG and OHT. Furthermore, SLT efficacy does not seem to be affected by prior PGA administration; however, larger cohort, comparative, multicenter RCTs are necessary to answer this question.

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.

A Review of Selective Laser Trabeculoplasty: “The Hype Is Real”

Presently, there is no efficacious treatment for glaucomatous optic neuropathy; the current treatment is focused on lowering intraocular pressure (IOP). Studies have demonstrated the safety and efficacy of selective laser trabeculoplasty (SLT) in reducing the IOP in eyes with open-angle (OAG) glaucoma or ocular hypertension (OH). Moreover, the European Glaucoma Society has instated SLT as the first-line or adjunctive treatment in OAG or OH, reiterating its clinical significance. In this review, we outline the old and the new roles of SLT, with an emphasis on clinical practice, and look further into its renewed appeal and future developments.

[Secondary open-angle glaucoma: pseudoexfoliative glaucoma, pigmentary glaucoma and neovascular glaucoma]

Secondary open-angle glaucomas are a heterogeneous group of diseases in which a variety of pathophysiological mechanisms result in an elevation of intraocular pressure. This article is the first part of a review of the more common forms of secondary open-angle glaucomas. The pathogenesis, characteristic clinical findings and treatment of pseudoexfoliative glaucoma, pigmentary glaucoma and neovascular glaucoma are discussed. An emphasis is placed on the differences in treatment compared to primary open-angle glaucoma and prophylactic treatment approaches are explained where possible.

[Comparative evaluation of hypotensive effectiveness of topical monotherapy and selective laser trabeculectomy]

PURPOSE

Comparison of the hypotensive effects of selective laser trabeculoplasty (SLT) and drug therapy in patients with newly diagnosed primary open-angle glaucoma (POAG) and ocular hypertension.

MATERIAL AND METHODS

Thirty patients (30 eyes) with newly diagnosed ophthalmic hypertension or POAG were observed. Patients of the 1st group (15 eyes) underwent standard SLT as a starting treatment, patients of the 2nd group (15 eyes) were prescribed monotherapy with a prostaglandin analog. Corneal compensated intraocular pressure (IOPcc) was measured for each patient using Ocular Response Analyzer («Reichert Technologies», USA). The observation period lasted 6 months.

RESULTS

During the 6-months follow-up, tafluprost was found to effectively reduce IOP in 93.3% of cases, SLT - in 73.3% of cases. There were no statistically significant differences in hypotensive effectiveness between the two compared treatments, which amounted to 27.9-28.5% reduction from the baseline values.

CONCLUSION

Selective laser trabeculectomy and topical drug therapy have shown similar hypotensive effectiveness during the 6-months follow-up when used as the initial therapy for POAG.

Five-Year Long-Term Follow-Up of Selective Laser Trabeculoplasty in Open-Angle Glaucoma

PURPOSE

Selective laser trabeculoplasty (SLT) is known as a safe laser therapy for an effective reduction in intraocular pressure (IOP). The aim of this study was to examine the therapeutic success of SLT in open-angle glaucoma (OAG) patients with a long-term follow-up of 5 years.

METHODS

Forty-six eyes of forty OAG patients, some with previous intraocular surgery, underwent SLT (24 males, 16 females). Therapeutic success was categorized as: category (I) - IOP reduction ≤ 21 mmHg and > 20% compared to baseline IOP with additional glaucoma medication; category (II) - IOP reduction ≤ 18 mmHg and > 30% compared to baseline IOP with additional glaucoma medication; category (III) - IOP reduction ≤ 18 mmHg without any additional glaucoma medication at all follow-ups. Therapeutic failure was defined as the necessity of any further glaucoma surgery (IV).

RESULTS

(1) SLT was well tolerated in all eyes, and no severe side effects or complications were recorded. (2) After 1-year follow-up, therapeutic success was 27% (I), 30% (II), and 3% (III). The therapeutic failure rate was 40% (IV). (3) After 2 years follow-up, therapeutic success was 7% (I), 10% (II), and 0% (III). The therapeutic failure rate was 83% (IV). (4) After 3 years follow-up, the therapeutic failure rate increased up to 100% (IV).

CONCLUSION

SLT seemed to be effective in lowering IOP in the first year in the present cohort, however, the long-term effect is low and additional local therapy or surgical interventions are necessary.

[Pigmentary glaucoma: yesterday, today, tomorrow]

Pigment dispersion syndrome (PDS) is a condition that mostly affects young men with myopic refraction. PDS is characterized by the presence of Krukenberg spindle, peripheral iris defects, significant trabecular meshwork pigmentation, as well as convex iris configuration. Such configuration can cause friction of iris's posterior pigment layer on its ligaments, which leads to the release of pigment and its accumulation mostly in the structures of the anterior chamber. Over time PDS can progress into pigmentary glaucoma (PG), which in turn can lead to permanent loss of vision. This review analyzes available data on diagnosis and treatment of PDS and PG.

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.

Pigment dispersion syndrome and its implications for glaucoma

Pigment dispersion syndrome (PDS) represents a clinical spectrum of a relatively common and usually underdiagnosed phenomenon produced by spontaneous pigment dispersion from the iris into the anterior segment. PDS is often bilateral, has no gender predisposition, and presents at a young age, particularly in myopes. Although most patients experiencing an episode of pigment dispersion are asymptomatic, extreme photophobia, ocular pain, redness, and blurred vision may occur. Other characteristic signs are iridolenticular contact, concave iris configuration, 360° peripheral iris transillumination, and pigment deposition on the anterior chamber angle or the corneal endothelium (Krukenberg spindle). Early PDS diagnosis is crucial to detect patients with pigment-related ocular hypertension (POHT) that can eventually lead to pigmentary glaucoma (PG). The latter represents a sight-threatening condition in which mechanical, environmental, and genetic factors contribute to optic nerve damage. In this review, we update the pathogenic mechanisms involved in the clinical spectrum of the disease. We describe its clinical presentation, ophthalmologic manifestations, and complications, including the factors influencing the development of POHT and PG. Because PDS has variable clinical presentations that lead to misdiagnoses, we emphasize the differential diagnosis and the actual therapeutic strategies according to disease status.

XEN® Gel Stent: A Comprehensive Review on Its Use as a Treatment Option for Refractory Glaucoma

The XEN Gel Microstent is a subconjunctival microinvasive glaucoma surgical device developed with the aim of improving the predictability and safety profile of bleb-forming glaucoma surgical procedures. The stent is a hydrophilic tube composed of a porcine gel cross-linked with glutaraldehyde with good stability and biocompatibility with minimal tissue reaction. This device has demonstrated promising outcomes with fewer risks compared to traditional surgeries. The aim of the review is to present early studies on different designs of the XEN Gel Stent, to summarize different surgical techniques of implantation and to analyze more comprehensively the results, complications and rates of needling of the commercially available device (Xen 45). The review will address separately special cases (PXG, UVG, ICE, congenital glaucoma) and describe small series and case reports.

Predictive Factors for Outcomes of Selective Laser Trabeculoplasty

We sought to  determine predictive factors for selective laser trabeculoplasty (SLT) outcome. 252 eyes from 198 adult patients with open-angle glaucoma who underwent SLT between July 2016 and February 2018 with a minimum 6 month follow up were reviewed. We defined success as ≥20% IOP reduction or ≥1 medication reduction without an IOP lowering procedure. We also evaluated the relationship of these factors to postoperative IOP elevation >5 mmHg (IOP spikes). Our primary outcome measure was association between age, type and severity of glaucoma, pigmentation of the trabecular meshwork (PTM), total energy delivered, and baseline intraocular pressure (IOP) with success. At 2 and 6 months, 33.6% (76/226) and 38.5% (97/252) of eyes met success criteria respectively. Baseline IOP > 18 mmHg was significantly associated with success both at 2 and 6 months, reducing IOP by 5.4 ± 5.3 mmHg (23.7% reduction), whereas those with lower baseline remained at −0.7 ± 4.6 mmHg (4.9% increase) at 6 months (P < 0.001). No other baseline characteristics significantly predicted success or IOP spikes. Patients with higher baseline IOPs had greater success rates and mean IOP reduction at both 2 and 6 months following SLT. Age, type and severity of glaucoma, PTM, or total energy delivery had no association with procedural success or IOP spikes. Patients with higher baseline IOP may experience greater lowering of IOP after SLT. However, SLT may be equally successful for patients with a variety of other characteristics.

Intraocular pressure reduction in a pigmentary glaucoma model by Goniotome Ab interno trabeculectomy

PURPOSE

To investigate whether microsurgical excision of trabecular meshwork (TM) in an ex vivo pigmentary glaucoma model can normalize the hypertensive phenotype.

METHODS

Eight eyes of a porcine pigmentary glaucoma model underwent 90° of microsurgical TM excision with an aspirating dual-blade (Goniotome (G)). 24 hours later, additional 90° of TM were removed. Anterior segments with sham surgeries served as the control (C). Outflow facility and intraocular pressure (IOP) were analyzed. Histology with hematoxylin and eosin (H&E) was obtained.

RESULTS

After the first 90° TM excision, IOP was significantly lower in G (10.2±2.4 mmHg, n = 7) than C (20.0±2.0mmHg, n = 8, P<0.01). Outflow facility in G (0.38±0.07 μl/min/mmHg) was higher than C (0.16±0.02 μl/min/mmHg, P<0.01). After the second 90° TM excision, IOP in G (6.46±0.81 mmHg, n = 7) was significantly lower than C (20.3±1.7 mmHg, n = 8, P<0.001), while the outflow facility in G (0.50±0.05 μl/min/mmHg, n = 7) was higher than C (0.16±0.01 μl/min/mmHg, n = 8, P<0.001). Compared to the first excision, excision of an additional 90° did not change of IOP (P = 0.20) or outflow facility (P = 0.17) further.

CONCLUSIONS

Excision of 90° of TM in a pigmentary glaucoma model using an aspirating dual-blade decreased IOP and increased outflow facility.

Hydrus microstent implantation for surgical management of glaucoma: a review of design, efficacy and safety

With the advent of microinvasive glaucoma surgery (MIGS), the spectrum of modalities available to manage patients with this chronic and heterogeneous condition has broadened. Despite its novelty however, there has been a rapid evolution in the development of a multitude of devices, each targeting a structure along the aqueous drainage pathway. A growing body of evidence has demonstrated IOP and medication burden reduction, and a more favorable safety profile with MIGS procedures in contrast to traditional incisional surgeries. Among the array of MIGS, the Hydrus® Microstent (Ivantis, Inc., Irvine, CA) is a recent FDA approved device, designed to bypass the trabecular meshwork and provide a scaffold for Schlemm’s canal. The objective of this article is to review the Hydrus from conception to clinical use, and present data on its efficacy and safety to date. The available literature has shown promise, however inherent to all novel devices, only long-term monitoring will ensure sustained IOP control and an acceptable safety profile. Surgical advancements in glaucoma have revolutionized the field, and continued research and development will establish these approaches in clinical treatment algorithms.

Comparison of successful outcome predictors for MicroPulse® laser trabeculoplasty and selective laser trabeculoplasty at 6 months

Purpose: To identify and compare factors predictive of successful outcome for MicroPulse^® laser trabeculoplasty (MLT) and selective laser trabeculoplasty (SLT).

Methods: 50 MLT-treated eyes and 50 SLT-treated eyes of open-angle glaucoma patients were reviewed for baseline characteristics, pre- and postoperative IOP and medications, and adverse events including postoperative IOP elevation >5 mmHg (IOP spikes) through 6 months of follow-up. Success was defined as ≥20% IOP reduction or ≥1 medication reduction without additional IOP lowering procedures at 6 months follow-up.

Results: MLT and SLT had similar success rates (44% vs 40%, P=0.983). Older age predicted success for SLT (P=0.013) but not MLT (P=0.154). Both MLT and SLT led to greater IOP lowering in patients with baseline IOP >18 mmHg, but only for SLT did baseline IOP have a significant association with success (P=0.035 vs P=0.983). Number of laser shots was associated with success in MLT (P=0.031) but not in SLT (P=0.970). Glaucoma severity and pigmentation of the trabecular meshwork (PTM) were not associated with rate of success for either group. The rate of IOP spikes was significantly (P=0.022) higher in the SLT group (10%) compared to none in the MLT group. No other complications or visually significant adverse events occurred in either group.

Conclusion: Although MLT and SLT resulted in similar success rates, older age and higher baseline IOP predicted success for SLT while MLT was equally efficacious regardless of these factors. Glaucoma severity and PTM were not associated with success of either laser procedures. 10% of SLT patients experienced IOP spike post procedure, whereas none in the MLT group did. MLT may be a safer alternative to SLT that is effective in lowering IOP and need for medications for a wider variety of patients with open angle glaucoma.

Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use:

https://youtu.be/dSsXRth9lVA

Pigment dispersion syndrome and pigmentary glaucoma: a review and update

INTRODUCTION

Pigment dispersion syndrome (PDS) is a condition where anomalous iridozonular contact leads to pigment dispersion throughout the anterior segment and the released pigment is abnormally deposited on various ocular structures.

CLINICAL PRESENTATION

The clinical presentation of PDS is defined by the presence of pigmented cells on the corneal endothelium, an increase of pigmentation of the trabecular meshwork, and mid-periphery transillumination defects of the iris. This syndrome, more common in myopes, is usually bilateral and can be associated with ocular hypertension or glaucoma. Secondary open-angle pigmentary glaucoma (PG) can develop due to reduction of the outflow of aqueous humour and consequent increase in intraocular pressure leading to glaucomatous optic neuropathy. Diagnosis of PG is commonly between 40 and 50 years of age, occurring more frequently in men. The advent of ultrasound biomicroscopy and anterior segment optical coherence tomography has contributed to enhancing our knowledge on the condition. Typical alterations of the anterior segment are the posterior insertion of the iris and iris concavity. Treatment of PG should be initiated early to hinder disease progression, glaucomatous damage, and vision loss. Management is based on medical therapy, laser iridotomy, selective laser trabeculoplasty, and filtration procedures.

CONCLUSIONS

The differential diagnosis of PDS with other disorders can be challenging and awareness of the condition together with meticulous ophthalmologic examination allows early diagnosis followed by appropriate management strategies. The present review is a comprehensive report on the clinical characteristics, pathogenesis, current management, and status quo of PDS and PG.

A Review of the Clinical Usefulness of Selective Laser Trabeculoplasty in Exfoliative Glaucoma

In the last decade, selective laser trabeculoplasty (SLT) has been commonly used in the management of several different types of glaucoma, as either primary or adjunct therapy. The technique has an excellent safety profile and is at least as effective as argon laser trabeculoplasty. Although the actual mechanism of action of SLT remains unclear, evidence has shown that it does not induce morphologically evident trabecular meshwork alterations. SLT's non-disruptive mode of action offers the advantage of repeatability. Exfoliation glaucoma (XFG) is a secondary open-angle glaucoma with unfavorable intraocular pressure (IOP) characteristics, which typically carries a poorer long-term prognosis than primary open-angle glaucoma. Consequently, patients with XFG often need multiple medications to achieve IOP levels that prevent disease progression. Because complicated pharmacotherapy regimens undermine the long-term tolerability and compliance of patients with XFG, options such as SLT may decrease the burden of multiple therapies and ultimately improve prognosis. In fact, SLT may be a particularly attractive option in XFG because the pigment-laden trabecular tissue of these patients enhances the absorption of laser energy and thus augments the biologic effects induced by this treatment. The current article reviews the postulated mechanisms of action of SLT, discusses practical aspects of SLT therapy, and examines selected peer-reviewed literature pertaining to the clinical usefulness of this modality in XFG patients.

[Pseudoexfoliation syndrome and pseudoexfoliation glaucoma]

Pseudoexfoliation syndrome is an age-related systemic disease that mainly affects the anterior structures of the eye. Despite a worldwide distribution, reported incidence and prevalence of this syndrome vary widely between ethnicities and geographical areas. The exfoliative material is composed mainly of abnormal cross-linked fibrils that accumulate progressively in some organs such as the heart, blood vessels, lungs or meninges, and particularly in the anterior structures of the eye. The exact pathophysiological process still remains unclear but the association of genetic and environmental factors are thought to play a role in the development and progressive extracellular accumulation of exfoliative material. Hence, LOXL1 gene polymorphisms, responsible for metabolism of some components of elastic fibers and extracellular matrix, and increased natural exposure to ambient ultraviolet or caffeine consumption have been associated with pseudoexfoliation syndrome. Ophthalmological manifestations are commonly bilateral with an asymmetric presentation and can lead to severe visual impairment and blindness more frequently than in the general population, mainly related to glaucoma and cataract. Pseudoexfoliation glaucoma is a major complication of pseudoexfoliation syndrome and represents the main cause of identifiable glaucoma worldwide. Visual field progression is more rapid than that observed in primary open angle glaucoma, and filtering surgery is more frequently required. Nuclear cataract is more frequent and occurs earlier than in the general population. Owing to poorer pupil dilation and increased zonular instability, cataract surgery with pseudoexfoliation is associated with a 5- to 10-fold increase in surgical complications compared to cataract surgery without pseudoexfoliation. Some specific treatments targeting production, formation or accumulation of exfoliative material could improve the prognosis of this syndrome.

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.

Transscleral Selective Laser Trabeculoplasty Without a Gonioscopy Lens

PURPOSE OF THE STUDY

The purpose of the study was to investigate results of selective laser trabeculoplasty (SLT) performed directly on the sclera without a gonioscopy lens.

DESIGN

Interventional case series, prospective, randomized, masked, controlled clinical trial.

METHODS

Setting: Meir Medical Center, Kfar-Saba, Israel.

STUDY POPULATION

Adults with uncontrolled primary open angle or pseudoexfoliation glaucoma randomized into 2 groups.

INTERVENTION

The controls underwent conventional SLT with 100 spots delivered using a gonioscopy lens for 360 degrees of the trabecular meshwork. The study group underwent irradiation using the same parameters with the laser applications administered on the perilimbal sclera. Study visits: 1 hour, 1, 7, 30, 60, 180, and 365 days postprocedure.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP) and side effects.

RESULTS

Thirty adults were randomized into 2 groups. The mean (±SD) pretreatment IOP was 20.21±3.19 mm Hg for the study group (n=14) and 21.14±2.98 mm Hg for the controls (n=14; P =0.43), dropping to 15.50±3.77 and 15.00±4.08 mm Hg (P =0.74) after 6 months and to 16.00±3.31 and 14.00±2.45 mm Hg (P =0.22) after 12 months. The average IOP reduction after 6 and 12 months was 23.4% and 20.83% for the study group and 27.1% and 33.77% for the controls (P=0.528). Success (a decrease of ≥15% at 6 months with no additional medications, laser, or glaucoma surgery) was achieved in 12 (85.7%) study patients and 9 (69.2%) controls (P=0.385). Complications were mild and transient (n=30), although significantly higher in the controls (n=15; P <0.0001).

CONCLUSIONS

SLT applied directly to the perilimbal sclera may be as efficacious as the conventional procedure for 1 year.

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.

Update on pigment dispersion syndrome and pigmentary glaucoma

PURPOSE OF REVIEW

The present article reviews the clinical features and pathogenesis of pigment dispersion syndrome and pigmentary glaucoma and provides an update regarding their diagnosis and management.

RECENT FINDINGS

Newer imaging modalities including ultrasound biomicroscopy and anterior segment optical coherence tomography facilitate visualization of the iris concavity characteristic of eyes with pigment dispersion syndrome and pigmentary glaucoma. Patients with pigmentary glaucoma may be distinguished from those with other glaucoma types by the presence of typical symptoms, personality type, and patterns of diurnal intraocular pressure fluctuation. Although laser iridotomy has been shown to alter iris anatomy in pigmentary glaucoma, it is not proven to slow visual field progression. Multiple trials have validated the safety and efficacy of filtering surgery in treating pigmentary glaucoma, with fewer studies published on the role of micro-invasive glaucoma surgery.

SUMMARY

Literature from the review period has further defined the unique clinical characteristics of pigment dispersion syndrome and pigmentary glaucoma. Laser surgery has a limited role in the management of these entities, whereas trabeculectomy remains an acceptable first-line surgical treatment. Further studies are needed to define the potential application of the newer micro-invasive glaucoma procedures in pigmentary glaucoma.

Perioperative medications for preventing temporarily increased intraocular pressure after laser trabeculoplasty

BACKGROUND

Glaucoma is the international leading cause of irreversible blindness. Intraocular pressure (IOP) is the only currently known modifiable risk factor; it can be reduced by medications, incisional surgery, or laser trabeculoplasty (LTP). LTP reduces IOP by 25% to 30% from baseline, but early acute IOP elevation after LTP is a common adverse effect. Most of these IOP elevations are transient, but temporarily elevated IOP may cause further optic nerve damage, worsening of glaucoma requiring additional therapy, and permanent vision loss. Antihypertensive prophylaxis with medications such as acetazolamide, apraclonidine, brimonidine, dipivefrin, pilocarpine, and timolol have been recommended to blunt and treat the postoperative IOP spike and associated pain and discomfort. Conversely, other researchers have observed that early postoperative IOP rise happens regardless of whether people receive perioperative glaucoma medications. It is unclear whether perioperative administration of antiglaucoma medications may be helpful in preventing or reducing the occurrence of postoperative IOP elevation.

OBJECTIVES

To assess the effectiveness of medications administered perioperatively to prevent temporarily increased intraocular pressure (IOP) after laser trabeculoplasty (LTP) in people with open-angle glaucoma (OAG).

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 11), MEDLINE Ovid (1946 to 18 November 2016), Embase.com (1947 to 18 November 2016), PubMed (1948 to 18 November 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 18 November 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com); last searched 17 September 2013, ClinicalTrials.gov (www.clinicaltrials.gov); searched 18 November 2016 and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 18 November 2016. We did not use any date or language restrictions.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in which participants with OAG received LTP. We included trials which compared any antiglaucoma medication with no medication, one type of antiglaucoma medication compared with another type of antiglaucoma medication, or different timings of medication.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened records retrieved by the database searches, assessed the risk of bias, and abstracted data. We graded the certainty of the evidence using GRADE.

MAIN RESULTS

We included 22 trials that analyzed 2112 participants and identified no ongoing trials. We performed several comparisons of outcomes: one comparison of any antiglaucoma medication versus no medication or placebo, three comparisons of one antiglaucoma medication versus a different antiglaucoma mediation, and one comparison of antiglaucoma medication given before LTP to the same antiglaucoma medication given after LTP. Only one of the included trials used selective laser trabeculoplasty (SLT); the remaining trials used argon laser trabeculoplasty (ALT). Risk of bias issues were primarily in detection bias, reporting bias, and other potential bias due to studies funded by industry. Two potentially relevant studies are awaiting classification due to needing translation.In the comparison of any medication versus no medication/placebo, there was moderate-certainty evidence that the medication group had a lower risk of IOP increase of 10 mmHg or greater within two hours compared with the no medication/placebo group (risk ratio (RR) 0.05, 95% confidence interval (CI) 0.01 to 0.20). This trend favoring medication continued between two and 24 hours, but the evidence was of low and very low-certainty for an IOP increase of 5 mmHg or greater (RR 0.17, 95% CI 0.09 to 0.31) and 10 mmHg or greater (RR 0.22, 95% CI 0.11 to 0.42). Medication was favored over placebo/no medication with moderate-certainty in reducing IOP from the pre-LTP measurements for both within two hours and between two and 24 hours. At two hours, the mean difference (MD) in IOP between the medication group and the placebo/no medication group was -7.43 mmHg (95% CI -10.60 to -4.27); at between two and 24 hours, the medication group had a mean reduction in IOP of 5.32 mmHg more than the mean change in the placebo/no medication group (95% CI -7.37 to -3.28). Conjunctival blanching was an ocular adverse effect that was more common when brimonidine was given perioperatively compared with placebo in three studies.In our comparison of brimonidine versus apraclonidine, neither medication resulted in a lower risk of increased IOP of 5 mmHg or greater two hours of surgery; however, we were very uncertain about the estimate. There may be a greater mean decrease in IOP within two hours after LTP. We were unable to perform any meta-analyses for other review outcomes for this comparison.In our comparison of apraclonidine versus pilocarpine, we had insufficient data to perform meta-analyses to estimate effects on either of the primary outcomes. There was moderate-certainty evidence that neither medication was favored based on the mean change in IOP measurements from pre-LTP to two hours after surgery.In the comparison of medication given before LTP versus the same medication given after LTP, we had insufficient data for meta-analysis of IOP increase within two hours. For the risk of IOP increase of 5 mmHg or greater and 10 mmHg or greater at time points between two and 24 hours, there was no advantage of medication administration before or after LTP regarding the proportion of participants with an IOP spike (5 mmHg or greater: RR 0.82, 95% CI 0.25 to 2.63; 10 mmHg or greater: RR 1.55, 95% CI 0.19 to 12.43). For an IOP increase of 10 mmHg or greater, we had very low-certainty in the estimate, it would likely change with data from new studies.

AUTHORS' CONCLUSIONS

Perioperative medications are superior to no medication or placebo to prevent IOP spikes during the first two hours and up to 24 hours after LTP, but some medications can cause temporary conjunctival blanching, a short-term cosmetic effect. Overall, perioperative treatment was well tolerated and safe. Alpha-2 agonists are useful in helping to prevent IOP increases after LTP, but it is unclear whether one medication in this class of drugs is better than another. There was no notable difference between apraclonidine and pilocarpine in the outcomes we were able to assess. Future research should include participants who have been using these antiglaucoma medications for daily treatment of glaucoma before LTP was performed.

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.

Effect of alpha-2-agonist premedication on intraocular pressure after selective laser trabeculoplasty

Aim:

To determine the effect of alpha-2-agonist (AA) premedication (PM) on intraocular pressure (IOP) following selective laser trabeculoplasty (SLT).

Methods:

Retrospective cohort study of all patients undergoing 360° SLT at an institution with two prevalent practice patterns consisting of SLT performed with PM and without premedication (NPM) with AA. The association between pre- and post-operative IOP was evaluated using a linear regression model in 49 (59%) PM and 34 (41%) NPM eyes.

Results:

The prevalence of IOP elevations up to 5 mmHg 1 h postoperatively was similar in both groups, occurring in 18% of PM and in 15% of NPM. Elevations above 5 mmHg were seen in 4% of PM and 8% of NPM (P = 0.732). After correcting for age, gender, diagnosis, number of medications, and preoperative IOP, the presence or absence of AA PM had no significant association with any postoperative IOP (P > 0.5).

Conclusion:

The practice of using AAs before SLT and measuring IOP at 1 h has not been validated yet adds to expenses and workflow burden. Our retrospective study showed no significant correlation between PM and postoperative or longer-term IOP. IOP at 1 h should be measured in patients who cannot tolerate transient pressure elevations. Further studies are needed to elucidate this relationship.

Complications of selective laser trabeculoplasty: a review

Selective laser trabeculoplasty is a laser treatment to treat glaucoma. It was initially indicated for open-angle glaucoma but has been proven to be efficacious for various types of glaucoma. This review article summarizes the few rare complications that can be seen with selective laser trabeculoplasty. It also makes recommendations on how to avoid these problems and how to treat patients when these rare complications arise.

Evaluation of Color-Changing Effect and Complications After Nd: YAG Laser Application On Iris Surface

Background

The aim of this study was to evaluate the color-changing effect and adverse effects after Nd: YAG laser application on the iris surface of rabbit eyes.

Material/Methods

The study was performed on right eyes of 12 pigmented rabbits. A laser device that produces frequency doubled 532 nm wavelength Nd: YAG laser with 900 μm spot diameter was used. The laser was applied in 3 sessions at 2-week intervals, at energy levels of 0.8 mJ in Group A and 1.5 mJ in Group B. Slit-lamp examinations and measurements of intraocular pressure (IOP) using a Tono-Pen were performed before and 1 day after each laser session. Iris thickness (IT) was measured at the beginning and the end using an ultrasonic biomicroscope. The eyes were enucleated for histopathologic examination on day 60.

Results

On the first day after each laser session, maximum grade 1 anterior chamber flare and cells were observed in both groups. In all eyes, flare and cells disappeared at the end of the first week. There was no significant difference in the IOP and IT values between measurements performed prior to and after laser sessions during the study (p>0.05). None of the eyes showed complications such as corneal edema, hypopyon, posterior synechia, transillumination defect, or pupillary defect. In histopathological examinations, reduction in pigment density was more profound in Group B compared to Group A, which was statistically significant (p<0.019).

Conclusions

There were no serious complications apart from mild transient inflammatory signs. Change in iris color was more evident at the end of the second month.

Selective Laser Trabeculoplasty: An Update

Selective laser trabeculoplasty (SLT) is an effective treatment option for the reduction of intraocular pressure (IOP) in patients with ocular hypertension or open-angle glaucoma. The mechanism by which SLT lowers IOP is not completely understood and is likely multifactorial. Published studies indicate that SLT is at least as effective as argon laser trabeculoplasty or medications at lowering IOP in many forms of glaucoma. In addition to IOP reduction, SLT may decrease IOP fluctuation and can be successfully used as primary or adjunctive therapy for the management of both early and advanced glaucoma. However, SLT may not be effective in certain forms of glaucoma, and the IOP-lowering effect seems to wane with time. High pretreatment IOP is the strongest predictor of treatment success, even in patients with normal-tension glaucoma. Repeatability of SLT has been controversial, but recent evidence suggests that it can be successfully repeated to achieve additional or recurrent IOP reduction, even in eyes that only had a modest response to initial treatment. Adverse events are uncommon after SLT, and the most common complications such as discomfort and inflammation are typically mild and transient. Further investigation is required to determine the optimal treatment parameters for SLT treatment. Limited evidence suggests that SLT is cost-effective as primary therapy for patients with glaucoma.

Selective laser trabeculoplasty: current perspectives

Selective laser trabeculoplasty (SLT) has been used in the treatment of glaucoma for just over a decade. Here, we review the current literature in terms of suggested mechanism, efficacy, method of treatment, predictors of success, adverse events, repeatability, and cost of SLT. The exact mechanism by which SLT lowers intraocular pressure (IOP) remains unknown although circumstantial evidence has come in many forms in relation to structural alteration; oxidative stress and inflammatory responses; tight junction integrity; proliferative responses; and microbubble formation. SLT is as effective as argon laser trabeculoplasty and medications in reducing IOP in glaucoma and ocular hypertension. The treatment is not uniformly effective in all eyes, and its IOP-lowering effect decreases over time. High pretreatment IOP is the strongest predictor of success; however, significant pressure reduction has also been shown in normal-tension glaucoma and in patients already taking multiple antiglaucoma drops. Mild, transient adverse effects are common. Transient IOP spikes usually resolve quickly with or without antiglaucoma treatment but may be problematic in pigmented angles. The limited available evidence suggests SLT is repeatable and cost-effective for the treatment of glaucoma and ocular hypertension.

Selective laser trabeculoplasty as a first-line therapy: a review

Poor adherence with glaucoma medications has been well documented. There remains a significant unmet need for a relatively safe intraocular pressure (IOP)-lowering procedure that minimizes or eliminates patient participation, and thus reduce the incidence of treatment failures attributable to nonadherence. Selective laser trabeculoplasty (SLT) offers several advantages: It effectively reduces IOP in most patients with open-angle glaucoma, it is cost-effective compared with eye drops, it can be repeated if needed, and it eliminates the issue of adherence to medications when used as an initial treatment. This article reviews the evidence supporting the use of SLT as a first-line therapy in glaucoma.

Long-term outcomes of selective laser trabeculoplasty (SLT) treatment in pigmentary glaucoma patients

PURPOSE

The aim of the present study was to assess the long-term efficacy of selective laser trabeculoplasty (SLT) treatment in patients suffering from pigmentary glaucoma (PG).

METHODS

Retrospective chart review of eyes suffering from PG that underwent SLT between January 1, 2005 and December 31, 2006. The primary outcome measure was time to failure after SLT treatment. Failure after SLT was defined as any 1 or more of the following: <20% intraocular pressure reduction, change in the medical treatment, performance of a further SLT treatment, and the patient being sent for surgery. All patients were treated over 180 degrees with SLT.

RESULTS

Thirty eyes of thirty patients were identified. The average time to failure after SLT was 27.4 months. The success rate after 12 months was 85%, after 24 months 67%, after 36 months 44%, and after 48 months 14%.

CONCLUSIONS

The long-term effects of SLT in PG when eyes were treated over 180 degrees seem to be low.

[Selective Laser Trabeculoplasty in the treatment of chronic open-angle glaucoma: retrospective analysis 12 years after treatment in a cohort of 28 patients]

PURPOSE

To determine long-term efficacy of selective Laser Trabeculoplasty (SLT) over 12 years in chronic open-angle glaucoma (OAG) patients.

METHODS

In this retrospective study, all patients treated by SLT between 1997 and 1999 for OAG were included and followed up every 6 months. The procedure was performed with a Coherent Selecta 7000 Nd:YAG with 100 ± 10 non overlapping 400 μm spots over 360 degrees centered on the trabecular meshwork. Patients were excluded in the case of prior filtration surgery or Argon laser trabeculoplasty. Our primary study parameter was the number of patients requiring filtration surgery within the follow-up period. Our secondary parameters were intraocular pressure (IOP) and SLT-related complications.

RESULTS

We included 46 eyes of 28 patients. The 12-year success rate was 26.1%. Thirty-nine percent of all eyes underwent filtration surgery (failure) during the follow-up period, and 34.8% were lost to follow-up. In the pigmentary glaucoma (PG) subgroup, the 12-year success rate was 16%, while it was 37.5% in the Primary OAG subgroup. The overall mean IOP was 22.8 mm Hg (D.S. 3.78) prior to laser, 16.08 mm Hg (D.S. 2.7) at 1 year and 15 mm Hg (D.S. 1.8) at 12 years. The mean number of medications was 1.6 (D.S. 0.8) prior to SLT, 1.36 (D.S. 0.8) at 1 year, and 1.3 (D.S. 1.2), 12 years after SLT respectively. No patients had a second SLT treatment. No significant complications occurred during follow-up.

CONCLUSION

Selective laser trabeculoplasty may at times be a useful resource to lower IOP in patients with OAG. Nonetheless, the failure rate is significant especially in PG, which requires confirmation by larger prospective studies.

Predictors of success in selective laser trabeculoplasty for primary open angle glaucoma in Chinese

Purpose

To determine the predictors of success for adjuvant selective laser trabeculoplasty (SLT) in Chinese primary open angle glaucoma (POAG) patients.

Methods

This prospective study recruited Chinese subjects with unilateral or bilateral POAG currently taking medication to reduce intraocular pressure (IOP). All subjects received a single session of 360° SLT treatment and continued their medications for 1 month. SLT success was defined as IOP reduction ≥20% at 1 month. The following covariates were analyzed in both groups via univariate and multivariate analyses: age, sex, lens status, initial IOPs, post-SLT IOPs, number and type of medications, SLT shots and energy, and pre-SLT investigations.

Results

In 51 eyes of 33 POAG subjects, the success rate of SLT was 47.1%. Certain groups of patients were associated with greater success using univariate analysis. These groups included the following: older age (coefficient =0.1; OR: 1.1; P=0.0003), a higher pre-SLT IOP (coefficient =0.3; OR: 1.3; P=0.0005), using four types of antiglaucoma medication (coefficient =2.1; OR: 8.4; P=0.005), a greater degree of spherical equivalent (coefficient =2.1; OR: 8.4; P=0.005), and the use of a topical carbonic anhydrase inhibitor (coefficient =1.7; OR: 6.0; P=0.003). None of the covariates were significant using multivariate analysis.

Conclusion

Older age, a higher pretreatment IOP, using multiple antiglaucoma medications especially topical carbonic anhydrase inhibitor, and higher refractive errors were associated with greater SLT success.

Selective Laser Trabeculoplasty: A Clinical Review

Selective laser trabeculoplasty (SLT) is a safe and effective treatment modality for lowering the intraocular pressure in patients with glaucoma. It achieves its results by selective absorption of energy in the trabecular pigmented cells, sparing adjacent cells and tissues from thermal damage, with minimal morphological tissue alteration following treatment. On the basis of the peer-reviewed medical literature, SLT is efficacious in lowering IOP, as initial treatment or when medical therapy is insufficient in all types of open-angle glaucoma in all races. SLT achieves intraocular pressure reduction similar to that of argon laser trabeculoplasty but without the tissue destruction and side effects. Observed side effects following SLT were almost uniformly transient and minor. We review highlights of recently published studies on the mechanisms and clinical outcome of SLT in order to address frequently raised issues pertinent to SLT in the clinical practice.

KEY MESSAGES

Selective laser trabeculoplasty is a safe and effective treatment modality for lowering the intraocular pressure in patients with glaucoma. How to cite this article: Alon S. Selective Laser Trabeculoplasty: A Clinical Review. J Current Glau Prac 2013; 7(2):58-65.

Comparison of the efficacy and safety of selective laser trabeculoplasty in cases with primary open-angle glaucoma and pseudoexfoliative glaucoma

The purpose of this study was to compare the efficacy and safety of selective laser trabeculoplasty (SLT) for patients with primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma (PXG). In this retrospective case series, 85 eyes (48 POAG, 37 PXG) of 85 patients were investigated. The medical records of patients who underwent SLT for POAG or PXG were reviewed. The main outcome measures included intraocular pressure (IOP)-lowering effect and ocular side effects. The mean decrease in IOP differed significantly (p < 0.001) between eyes with POAG (-4.4 ± 2.1 mmHg) and eyes with PXG (-6.1 ± 3.6 mmHg) at a mean follow-up period of 1 year. The rate of side effects, such as early IOP spike and uveitis, did not significantly differ between the two groups. In conclusion, SLT has a greater IOP-lowering effect in PXG compared with POAG.