Selective Laser Trabeculoplasty Treatment Research Articles

Wirksamkeit der selektiven Lasertrabekuloplastik bei Patienten mit unzureichender Augendrucksenkung unter maximaler Therapie

Reduction of intraocular pressure (IOP) is still the primary goal of glaucoma treatment. The aim of this prospective study was to examine the IOP lowering effect of selective laser trabeculoplasty (SLT) in patients on maximum tolerated medical therapy (MTMT), especially with regard to a potential influence of pseudophakia and topical prostaglandin analogues (PGA) on IOP reduction. A total of 30 patients with a diagnosis of primary open angle glaucoma, normal tension glaucoma and pseudoexfoliative glaucoma with uncontrolled IOP despite MTMT underwent SLT treatment circumferentially over 360°. Follow-up visits were conducted 1 day after SLT and then 1, 3, 6, 9, and 12 months post-treatment. The initial medication was continued unchanged for 3 months. Median follow-up was 11.97 ± 3.1 months, mean IOP at baseline was 19.60 ± 4.69mmHg, mean IOP reduction was -19.95 ± 17.14% 1 month after and -14.07 ± 23.57% 12 months after SLT (p < 0.001 and p = 0.003, respectively). Patients with higher baseline IOP had greater reduction of IOP after SLT (R(2) = 0.482, p < 0.001). Phakic patients had a significantly greater IOP reduction compared to pseudophakic patients (- 4.55 ± 4.45mmHg and + 2.75 ± 6.75mmHg, respectively, p = 0.010). Patients without PGA had a statistically insignificant greater IOP reduction compared to patients with PGA (- 7.40 ± 4.72mmHg and -2.48 ± 5.22mmHg, respectively, p = 0.066) and four patients needed additional surgery to lower IOP. Even in patients already on maximum IOP lowering medication, SLT has the potential to significantly reduce IOP up to 1 year after treatment. The IOP reduction is most pronounced in phakic eyes with high preoperative IOP.

The Influence of Topical Prostaglandin Analogues in Inflammation After Selective Laser Trabeculoplasty Treatment

Reducing intraocular pressure (IOP) seems to be the only treatment that slows progression in glaucoma. The IOP can be decreased by pharmaceutical treatment, laser [selective laser trabeculoplasty (SLT)] treatment, or surgery. Prostaglandin analogues have been postulated to share action mechanisms with SLT and to possibly diminish the effects of SLT treatment. The aim of the current study was to investigate the effects of prostaglandin analogues in inflammation and IOP reduction after SLT treatment. Prospective nonrandomized study. One hundred and eighteen patients were included in the study. Glaucoma (open-angle or pseudoexfoliation glaucoma) patients who will be treated with SLT. Inflammation was measured with a laser flare meter (Kowa FM-500). Measurements were made before SLT and then 2 h, 1 week, and 1 month after SLT treatment. IOP was also checked at the same time intervals. The SLT treatment was performed over 90°. All patients were divided into two groups: those receiving prostaglandins analogues and those treated with nonprostaglandin analogues. Inflammation before and after SLT showed no significant difference between the groups at all the time intervals studied (t-test, before: P=0.16; 2 h: P=0.14; 1 week: P=0.12; and 1 month: P=0.36). IOP reduction showed no significant difference between the groups (t-test, P=0.31). SLT treatment effects do not seem to be influenced by the use of prostaglandin analogues.

Selective Laser Trabeculoplasty in Uncontrolled Pseudoexfoliation Glaucoma

To assess the efficacy and safety of selective laser trabeculoplasty (SLT) in uncontrolled pseudoexfoliation glaucoma (PEXG). Fifty-seven eyes (57 patients) with uncontrolled PEXG and intra-ocular pressure (IOP) greater than 23 mm Hg underwent SLT. All received ophthalmic evaluation preoperatively and at intervals postoperatively. IOP was measured at 1 hour, 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. During follow-up, patients were treated with topical anti-glaucoma medications as necessary. One year postoperatively, mean IOP in all patients decreased from 26.01 ± 2.5 to 17.8 ± 2.8 mm Hg (31.5%; P < .001). Mean medications per patient decreased from 2.8 to 2.3. Complications included conjunctival redness and infection within 1 day postoperatively in 30 eyes (67%). One hour after SLT treatment, an increase in IOP greater than 5 mm Hg was detected in two eyes (3.5%) and resolved within 24 hours with topical medication. SLT is safe and effective in patients with PEXG.

Trabecular meshwork gene expression after selective laser trabeculoplasty.

BackgroundTrabecular meshwork and Schlemm's canal are the tissues appointed to modulate the aqueous humour outflow from the anterior chamber. The impairment of their functions drives to an intraocular pressure increase. The selective laser trabeculoplasty is a laser therapy of the trabecular meshwork able to decrease intraocular pressure. The exact response mechanism to this treatment has not been clearly delineated yet. The herein presented study is aimed at studying the gene expression changes induced in trabecular meshwork cells by selective laser trabeculoplasty (SLT) in order to better understand the mechanisms subtending its efficacy.Methodology/Principal FindingsPrimary human trabecular meshwork cells cultured in fibroblast medium underwent selective laser trabeculoplasty treatment. RNA was extracted from a pool of cells 30 minutes after treatment while the remaining cells were further cultured and RNA was extracted respectively 2 and 6 hours after treatment. Control cells stored in incubator in absence of SLT treatment were used as reference samples. Gene expression was evaluated by hybridization on miRNA-microarray and laser scanner analysis. Scanning electron microscopic examination was performed on 2 Trabecular meshwork samples after SLT at 4th and 6th hour from treatment. On the whole, selective laser trabeculoplasty modulates in trabecular meshwork the expression of genes involved in cell motility, intercellular connections, extracellular matrix production, protein repair, DNA repair, membrane repair, reactive oxygen species production, glutamate toxicity, antioxidant activities, and inflammation.Conclusions/SignificanceSLT did not induce any phenotypic alteration in TM samples. TM is a complex tissue possessing a great variety of function pivotal for the active regulation of aqueous humour outflow from the anterior chamber. SLT is able to modulate these functions at the postgenomic molecular level without inducing damage either at molecular or phenotypic levels.

Long-Term Outcomes of Selective Laser Trabeculoplasty (SLT) Treatment

Purpose:Glaucoma is a progressive optic neuropathy that may lead to blindness. Reducing intraocular pressure (IOP) seems to be the only treatment that slows progression in glaucoma. IOP can be decreased by pharmaceutical treatment, laser treatment or surgery.The aim of the present study was to assess the long-term efficacy of selective laser trabeculoplasty (SLT) treatment. Methods:Retrospective chart review of eyes that underwent SLT between 1 January 2005 and 31 December 2005. The primary outcome measure was time to failure after SLT treatment. Failure after SLT was defined as any one or more of the following: change in the medical treatment, performance of a further SLT treatment, the patient being sent for surgery. All patients were treated over 90° with SLT.Results:120 eyes of 120 patients were identified. The average time to failure after SLT was 18 months. The success rate after 12 months was 62%, after 24 months 34%, after 36 months 28% and after 48 months 24%.Conclusions:The long-term effects of SLT when eyes were treated over 90° seem to be low. The authors recommend treating patients over 180°, as has traditionally been done. We suggest that this will improve the long-term results.

SLT and Adjunctive Medical Therapy

To investigate if specific classes of antiglaucoma medications have an influence on selective laser trabeculoplasty (SLT) success. This retrospective prediction rule analysis investigated 120 eyes from 120 patients diagnosed with either open angle glaucoma or ocular hypertension, who underwent SLT treatment. Treatment success was defined as ≥20% intraocular pressure (IOP) reduction at 3 and 6 months after the treatment date. Multivariate logistic regression analyses were performed to determine success predictors. Pre-SLT IOP (up to 4 wk before SLT therapy) was the only independent predictor for ≥20% IOP reduction with an odds ratio of 1.30 when controlling for pre-SLT antiglaucoma drops. The area under receiver operator characteristic curve was 0.777. Topical medications do not adversely, nor favorably, affect SLT success. SLT efficacy is positively associated with the degree of IOP elevation before SLT treatment. Pigmentation of the anterior chamber angle, class of antiglaucoma medications, diabetes, sex, corneal thickness, pseudophakia, diagnosis, washout of eye drops, and previous argon laser trabeculoplasty treatment are not associated with SLT treatment efficacy.

Inflammation assessment after selective laser trabeculoplasty (SLT) treatment

Selective laser trabeculoplasty (SLT) appears to be a safe and effective method to lower intraocular pressure (IOP). The exact mechanism of action for reducing IOP and inflammation levels is not known. The aim of this study was to assess inflammation after SLT treatment. Forty patients (80 eyes) were included in the study. Glaucoma (pigmentary and pseudoexfoliative glaucoma)/ocular hypertension patients that will be treated with SLT in just one eye, both with and without eye-drops. patients suffering from ocular or systemic inflammatory diseases are treated with cortisone or immunosuppressive drugs. Inflammation was measured in two different ways: (i) clinically with a slit lamp and classified 0-4; (ii) objectively with a 'Laser flare meter (Kowa FM 500)'. Measurements were taken before SLT, 2 hr, 1 week and 1 month after SLT treatment, both eyes were evaluated. IOP was also checked in the same way. SLT treatment was performed in 90°. Inflammation before and after SLT showed no significant difference measured clinically with slit lamp and objectively with the laser flare meter among the groups. No inflammation or IOP reduction was found in the untreated eyes. No IOP spikes after SLT treatment were found. Selective laser trabeculoplasty treatment seems not to induce inflammation in the anterior chamber when 90° was treated. SLT effectively and safely lowers IOP and might be considered as primary therapy.

Predictive factors of success in selective laser trabeculoplasty (SLT) treatment

Purpose:Glaucoma is a progressive optic neuropathy that may lead to blindness. Reducing intraocular pressure (IOP) is the only known treatment to slow progression in glaucoma. IOP can be reduced by pharmaceutical treatment, laser and surgery. The aim of the present study was to assess predictive factors of success after selective laser trabeculoplasty (SLT) treatment.Methods:We used a retrospective chart review of eyes that underwent SLT between January 1, 2005 and December 31, 2005. The dependent variable was time to failure after SLT treatment. Failure after SLT was defined as any changes in the medical treatment, and/or a new SLT treatment was performed and/or the patient was sent for surgery. All patients were treated with 90° SLT. A multivariate regression analysis was performed to assess correlation between time to failure after SLT and age, gender, IOP before treatment, number of medications used, SLT number, amount of spots, laser energy used, grade of angle, pigmentation and diagnosis.Results:120 eyes of 120 patients were identified. The average time to failure after SLT was 18 months. The predictive factors identified were: age, IOP before SLT and dose.Conclusion:Predictive factors identified in our study were high baseline IOP, age and amount of laser energy used. Our study confirms previous results about baseline IOP as a predictive factor.

Comparison of selective laser trabeculoplasty (SLT) in primary open angle glaucoma and pseudoexfoliation glaucoma

Background and objectiveThe aim of the present study was to compare intraocular pressure (IOP) reduction and inflammation after selective laser trabeculoplasty (SLT) treatment in patients suffering from primary open angle (POAG) vs pseudoexfoliative (PXFG) glaucoma.Study design/patients and methodsSixty patients (60 eyes) participated in the study. Glaucoma patients (POAG or PXFG) scheduled for treatment with SLT were included. Inflammation was measured with a laser flare meter (Kowa FM-500). Measurements were made before SLT and 2 hours, 1 week, and 1 month after SLT treatment. IOP was also checked at the same time intervals.ResultsInflammation after SLT showed no significant difference between the groups (t-test, before: P = 0.16; 2 hours: P = 0.14; 1 week: P = 0.12; and 1 month: P = 0.36). IOP reduction was the same in both groups (t-test, P = 0.27).ConclusionSLT safely reduces IOP in both POAG and PXFG. Pseudoexfoliation does not seem to be a risk factor for post-laser complications.

Selective Laser Trabeculoplasty after Failed Trabeculectomy in Open Angle Glaucoma

Objective: To determine the efficacy of selective laser trabeculoplasty (SLT) for uncontrolled open angle glaucoma (OAG) on maximal tolerated medical therapy and with a history of previously failed trabeculectomy. Methods: This was a prospective, non-randomized, interventional case series. Participants included 22 eyes of 20 consecutive glaucoma patients with a previously failed trabeculectomy and medically uncontrolled intraocular pressure, unable or unwilling to undergo further incisional surgery. A single SLT treatment was performed over 270° to 360°, and participants were followed for a minimum of 12 months. Success was defined in two separate analyses as 1) absolute IOP reduction ≥ 3 mm Hg and 2) percentage IOP reduction of 20% or 15% without additional laser or surgical intervention. Results: The mean IOP dropped from 20.8 mm Hg to 16.3 mm Hg 12 months after SLT. The mean reduction in IOP was 19.5% or 4.5 mm Hg (95% confidence interval, 1.06-7.92, p<0.001). The cumulative success rate at 12 months (3 mmHg IOP reduction) was 16%. There was no statistically significant change in the number of medications (2.2 ± 0.8 to 2.0 ± 1.1). Conclusions: In the short- and intermediate-term, SLT had mild to moderate success in achieving lower IOP in individuals with medically uncontrolled OAG with previously failed trabeculectomy.

Effect of primary selective laser trabeculoplasty on tonographic outflow facility: a randomised clinical trial

PurposeTo investigate the effect of 180° versus 360° primary selective laser trabeculoplasty (SLT) on tonographic outflow facility and intraocular pressure (IOP).DesignProspective, single masked randomised clinical trial.ParticipantsPatients with untreated primary open...

Selective Laser Trabeculoplasty in Pseudophakic Glaucoma.

Glaucoma following cataract operation is more common when complications occur during surgery. Patients who had posterior capsule rupture during cataract surgery usually have a prolonged intraoperative time and manipulation. In such cases, secondary glaucoma may develop due to chronic trabecular damage and prolong topical steroid use. It is usually treated with topical anti-glaucoma medication or surgery. Recently selective laser trabeculoplasty (SLT) has emerged as a relatively new, safe and effective treatment modality. Three cases of pseudophakic secondary glaucoma following complicated cataract surgery treated successfully with 180 degrees SLT treatment are presented. Case 1 responded well to SLT during 5-year available follow-up, along with reduction in topical anti-glaucoma medication. In Cases 2 and 3, SLT was used as adjunctive to topical anti-glaucoma medication and target intra ocular pressure (IOP) was maintained for 4 and 2 years of available follow-up, respectively. To our best knowledge this is the first case series where SLT has been shown effective in cases of pseudophakic secondary glaucoma.

The Impact of Anti-Inflammatory Therapy on Intraocular Pressure Reduction Following Selective Laser Trabeculoplasty

To determine whether the use of postoperative topical anti-inflammatory therapy affects the intraocular pressure (IOP)-lowering efficacy of selective laser trabeculoplasty in eyes with primary open-angle glaucoma. In this prospective, randomized, observer-masked study, 25 participants with primary open-angle glaucoma following bilateral 360 degrees selective laser trabeculoplasty used prednisolone acetate 1% four times daily in one randomly selected eye for 1 week. IOP was assessed at baseline and 1 week, 1 month, and 3 months after selective laser trabeculoplasty. Baseline IOP and selective laser trabeculoplasty treatment parameters were comparable in both groups. Mean IOP was similar in eyes that did and did not receive steroid therapy at 1 week (17.0 vs 16.3 mm Hg, respectively, P = .613), 1 month (16.8 vs 16.2 mm Hg, respectively; P = .571), and 3 months (16.0 vs 15.8 mm Hg, respectively; P = .819). A 1-week course of topical prednisolone acetate 1% four times daily did not affect the IOP-lowering effect of selective laser trabeculoplasty in eyes with primary open-angle glaucoma.

Inflammation assessment after selective laser trabeculoplasty (SLT) treatment

Abstract Purpose Glaucoma is a progressive neuropathy, reducing intraocular pressure (IOP) seems to be the only treatment to stop progression in glaucoma. There are several methods to reduce IOP: medical treatment, laser and surgery. Selective Laser Trabeculoplasty (SLT) is a new treatment alternative. SLT selectively targets the pigmented cells of the trabecular meshwork without causing thermal or collateral damage to the surroundings structures. The aim of the present study was to assess inflammation after SLT treatment. Methods 40 patients (80 eyes) were included in the study. Inclusion criteria: Glaucoma (POAG, pigmentary and pseudoexfoliative glaucoma)/ OHT patients that will be treated with SLT in just one eye, both with and without eye‐drops. Exclusion criteria: patients suffering from ocular or systemic inflammatory diseases or treated with cortisone or immunosuppressive drugs. Inflammation was measured in 2 different ways: 1) clinically with a slit lamp and classified 0‐4; 2) with a “Laser flare meter (Kowa FM 500)”. Measurements were done before, 2 hours after, 1 week and 1 month after SLT treatement, both eyes were evaluated. IOP was also checked in the same way. SLT treatment was performed in 90° with the SLT Solo Ellex laser. Results inflammation before and after SLT showed no significant difference measured both clinically with slit lamp and objectively with the laser flare meter. No inflammation was found in the untreated eyes. No IOP peaks after SLT treatment were found. Conclusion SLT treatment seems not to induce inflammation in the anterior chamber when 90° were treated. SLT treatment might be considered as a first choice treatment against high intraocular pressure.

Selective Laser Trabeculoplasty versus Argon Laser Trabeculoplasty in Patients with Uncontrolled Open-Angle Glaucoma

To compare the efficacy of selective laser trabeculoplasty (SLT) to argon laser trabeculoplasty (ALT) as treatment and retreatment to lower intraocular pressure (IOP) in patients with uncontrolled open-angle glaucoma (OAG) on maximally tolerated medication therapy with a follow-up of 12 months. A total of 120 eyes of 120 patients with uncontrolled OAG were enrolled in the study. Group A included patients with IOP >22 mmHg on maximal medical therapy. A total of 43 eyes underwent SLT treatment and 41 eyes underwent ALT treatment. At the end of the follow-up IOP was <18 mmHg. Group B included patients with IOP >20 mmHg at 3 months follow-up after SLT or ALT treatment. These patients were retreated randomly, 18 with SLT and 18 with ALT. In Group A at the end of the follow-up there was no statistically significant difference in IOP lowering between SLT (6.01 mmHg) and ALT (6.12) (p=0.794). In Group B at the end of the follow-up patients undergoing SLT presented IOP lowering statistically significant to ALT treatment (6.24 mmHg and 4.65 mmHg, respectively, p<0.01). SLT is effective as treatment for patients with OAG and appears to be equivalent to ALT in IOP lowering at 12 months only in patients without a prior treatment. In case of retreatment SLT appears to be better than ALT in IOP lowering.

A Comparison of the Intervisit Intraocular Pressure Fluctuation After 180 and 360 Degrees of Selective Laser Trabeculoplasty (SLT) as a Primary Therapy in Primary Open Angle Glaucoma and Ocular Hypertension

To determine and compare the effect of 180 and 360 degrees of selective laser trabeculoplasty (SLT) treatment as a primary therapy on the intervisit intraocular pressure (IOP) fluctuation in patients followed up for a period of 2 years without any further medical or surgical intervention. Retrospective chart review of patients with ocular hypertension and primary open angle glaucoma who received SLT as primary therapy without any subsequent medical or surgical intervention. IOP before SLT and postlaser IOP at all the visits during the follow-up period of months 6 to 24 was determined. The standard deviation (SD) of the mean IOP was used as a surrogate for IOP fluctuation. Forty-one eyes were treated by SLT, 19 eyes in the 180-degree group and 22 eyes in the 360-degree group. The mean reduction in IOP at 2 years was 28% in 180-degree group and 35% in 360-degree SLT group. After the SLT, the 360-degree SLT group had a lower IOP fluctuation compared with the 180-degree SLT group over the follow-up period of months 6 to 24. The percentage of eyes with intervisit IOP fluctuation (SD) <or=2 mm Hg during the same follow-up period was significantly greater in 360-degree SLT treatment group (86%) than in the 180-degree SLT treatment group (52%), P=0.03. The odds of achieving IOP fluctuation <or=2 mm Hg were 5.7 times greater with 360 degrees than with 180-degree SLT during the follow-up period of months 6 to 24. This study suggests that 360-degree SLT is more efficacious in achieving smaller IOP fluctuations than treatment with 180-degree SLT.

Matrix metalloproteinases and their tissue inhibitors after selective laser trabeculoplasty in pseudoexfoliative secondary glaucoma

BackgroundThe aim of this study was to assess changes in metalloproteinases (MMP-2) and tissue inhibitor of metalloproteinases (TIMP-2) following selective laser trabeculoplasty (SLT) in patients with pseudoexfoliative glaucoma (PEXG).MethodsWe enrolled 15 patients with PEXG and cataracts (PEXG-C group) and good intraocular pressure (IOP) controlled with β-blockers and dorzolamide eye drops who were treated by cataract phacoemulsification and 15 patients with pseudoexfoliative glaucoma (PEXG-SLT group). The PEXG-SLT patients underwent a trabeculectomy for uncontrolled IOP in the eye that showed increased IOP despite the maximum drug treatment with β-blockers and dorzolamide eye drops and after ineffective selective laser trabeculoplasty (SLT). The control group consisted of 15 subjects with cataracts. Aqueous humor was aspirated during surgery from patients with PEXG-C, PEXG-SLT and from matched control patients with cataracts during cataract surgery or trabeculectomy. The concentrations of MMP-2 and TIMP-2 in the aqueous humor were assessed with commercially available ELISA kits.ResultsIn PEXG-SLT group in the first 10 days after SLT treatment a significant reduction in IOP was observed: 25.8 ± 1.9 vs 18.1.0 ± 1.4 mm/Hg (p < 0.001), but after a mean time of 31.5 ± 7.6 days IOP increased and returned to pretreatment levels: 25.4 ± 1.6 mm/Hg (p < 0.591). Therefore a trabeculectomy was considered necessary.The MMP-2 in PEXG-C was 57.77 ± 9.25 μg/ml and in PEXG-SLT was 58.52 ± 9.66 μg/ml (p < 0.066). TIMP-2 was 105.19 ± 28.53 μg/ml in PEXG-C and 105.96 ± 27.65 μg/ml in PEXG-SLT (p < 0.202). The MMP-2/TIMP-2 ratio in the normal subjects was 1.11 ± 0.44. This ratio increase to 1.88 ± 0.65 in PEXG-C (p < 0.001) and to 1.87 ± 0.64 in PEXG-SLT (p < 0.001). There was no statistically significant difference between the PEXG-C and PEXG-SLT ratios (p < 0.671).ConclusionThis case series suggest that IOP elevation after SLT can be a serious adverse event in some PEXG patients. The IOP increase in these cases would be correlated to the failure to decrease the TIMP-2/MMP-2 ratio.Trial registrationCurrent Controlled Trials ISRCTN79745214

Development of a Prediction Rule to Estimate the Probability of Acceptable Intraocular Pressure Reduction After Selective Laser Trabeculoplasty in Open-angle Glaucoma and Ocular Hypertension

To develop and validate a prediction rule to estimate the probability of acceptable intraocular pressure (IOP) reduction after selective laser trabeculoplasty (SLT) in ocular hypertension and open-angle glaucoma. The study population was derived from a cohort of 220 patients with ocular hypertension, open-angle glaucoma, or normal tension glaucoma. A > or =20% reduction in IOP (mm Hg) from the baseline IOP at 6 months after SLT was considered treatment success. Logistic multivariate regression modeling was performed to develop a prediction rule. In multivariate logistic regression analyses, pre-SLT IOP and maximum IOP were identified as independent predictors for > or =20% IOP reduction at 6 months with adjusted odds ratios of 1.3 and 0.9, respectively, controlling for sex, diagnosis, pigment of anterior chamber, and washout of eye drops. The area under receiver operator characteristic curve was 0.716. Calibration of this prediction rule showed good agreement between predicted and observed probabilities of acceptable IOP reduction. If a probability of acceptable IOP reduction of 50% or greater is used as the minimal clinical threshold for treatment, the prediction rule had a sensitivity and specificity of 91.3% and 30.4%, respectively. SLT efficacy is positively associated with IOP elevation before SLT treatment and adversely associated with the maximum IOP ever recorded in history. Pigmentation of the anterior chamber angle, diagnosis, washout of eye drops, and sex are not associated with SLT treatment efficacy. This prediction rule should be further validated with a comparable prospective clinical study cohort.

The Effect of Selective Laser Trabeculoplasty on Intraocular Pressure in Patients With Intravitreal Steroid-induced Elevated Intraocular Pressure

To assess effectiveness of selective laser trabeculoplasty (SLT) in lowering intraocular pressure (IOP) in patients with steroid-induced elevated IOP. Retrospective review of 7 patients (7 eyes) with IOP elevation after intravitreal triamcinolone acetonide (4.0 mg/0.1 mL) injections for macular edema (6 patients) or central retinal vein occlusion (1 patient). Three patients had preexisting open angle glaucoma; 2 patients had preexisting ocular hypertension. Time between intraocular corticosteroid injection and subsequent increased IOP ranged from 5 to 29 weeks. After unsuccessful maximum tolerated medical therapy, patients underwent unilateral SLT between April 2003 and June 2005. IOP was measured 4 weeks prelaser; on the day of laser; within 3 weeks, and at 1, 3, and 6 months postlaser. Two-sample t test was used for analysis. The pre-SLT and post-SLT IOP measurements were the major outcome measures used to define the relative success of the SLT procedure. Seven patients were taking 4.0+/-0.8 ocular hypotensive medications before SLT. Preoperative IOP (mm Hg+/-SD) 38.4+/-7.3 decreased postoperative to 25.6+/-7.1 within 3 weeks (P<0.003), 25.9+/-8.8 at 1 month (P<0.007), 23.9+/-10.6 at 3 months (P<0.006), and 15.7+/-2.2 at 6 months (P<0.001). Four patients underwent a second SLT procedure. Two patients failed after the 3-month visit. IOP in fellow eyes of all patients was unchanged (P>0.080). SLT lowered (P<0.007) IOP in 5 eyes of 7 patients with steroid-induced increased IOP from 3 weeks to 6 months postoperative. Two patients required additional surgical procedures. Repeat SLT treatments may be necessary. SLT is a temporizing procedure to consider in patients with steroid-induced elevated IOP.

Projected cost comparison of selective laser trabeculoplasty versus glaucoma medication in the Ontario Health Insurance Plan

Background: The projected 6-year cost comparison of primary selective laser trabeculoplasty (SLT) versus primary medical therapy in the treatment of open-angle glaucoma for Ontario patients aged 65 years or more is presented. Costs are taken from the perspective of the Ontario Health Insurance Plan at a perpatient level. Methods: The cost of each medication was obtained from the 2003 Ontario Drug Benefits formulary. The average annual cost of medications was determined by estimating the provincial prescription rate of glaucoma medications, with reference to both a volume-per-bottle study of these drugs and a study of pharmacy claims reports. A representative provincial prescription rate was calculated by reviewing 707 patient charts selected randomly from 5 ophthalmologic practices across Ontario. Medication therapies were categorized into mono-, bi-, and tri-drug therapy groups. The cost of SLT was analyzed under the following 2 scenarios. SLT rep 2y assumed a duration of 2 years before repeat SLT was necessary. SLT rep 3y assumed a duration of 3 years before repeat SLT was necessary. Bilateral 180° SLT treatment and repeatability of SLT was assumed.The cost of surgery for patients who fail SLT or medical therapy was not accounted for in this study nor was the cost of patients who required medical therapy in conjunction with SLT. Results: In the SLT rep 2y scenario, the use of primary SLT over mono-, bi-, and tri-drug therapy produced a 6-year cumulative cost savings of $206.54, $1668.64, and $2992.67 per patient, respectively. In the SLT rep 3y scenario, the use of primary SLT over mono-, bi-, and tri-drug therapy produced a 6-year cumulative cost savings of $580.52, $2042.82, and $3366.65 per patient, respectively. Interpretation: Our findings suggest that SLT as primary therapy, at a per-patient level, offers a modest potential cost saving over primary medical therapy in the management of open-angle glaucoma for Ontario patients aged 65 years or more.