Open Angle Glaucoma
Conditions
Keywords
GLAUCOMA, MICROPULSE, LASER, TRABECULOPLASTY, OPEN ANGLE, INTRAOCULAR PRESSURE
Brief summary
The purpose of this study is to evaluate the effectiveness of a new laser (called Micropulse Laser Trabeculoplasty or MLT) in the treatment of glaucoma compared to the conventional laser presently used which is called selective laser trabeculoplasty or SLT. Both lasers (SLT and MLT) are used as standard of care in the treatment of open angle glaucoma.
Detailed description
Glaucoma is the 2nd leading cause of blindness worldwide and affects over 2.5 million Americans over the age of 40. It is thought that elevated intraocular pressure causes damage to the optic nerve fibers which leads to silent vision loss in glaucoma. Therefore, the primary approach to managing this disease process is through intraocular pressure reduction with a) topical drops that decrease intraocular fluid production or increase fluid outflow, b) laser therapy to the outflow structures in the eye (trabecular meshwork) to increase fluid egression, c) or incisional surgery with or without placement of setons to create a new pathway for fluid outflow. When medical therapy has been maximized or patients do not tolerate topical therapy, laser trabeculoplasty is common applied to achieve further intraocular pressure reduction. There are two types of laser therapies: argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT). The former involves applying laser to create outflow pathways in the trabecular meshwork (TM) and induces thermal damage to the TM. The latter selectively applies energy which induces inflammatory restructuring of the TM without creating a burn. Studies have shown comparable results between the two treatment modalities with SLT offering the advantage of repeatable treatment. Studies have also shown laser trabeculoplasty to be comparable to the effect of topical drops in intraocular pressure reduction. Side effects for both types of laser trabeculoplasty include post procedure intraocular pressure elevation and intraocular inflammation which is treated with topical drops after the procedure. This study aims to evaluate the effectiveness of micropulse laser trabeculoplasty in intraocular pressure reduction in patients with open angle glaucoma as compared to conventional selective laser trabeculoplasty. Secondary aims would be to determine whether its reduction is comparable to that of topical intraocular pressure lowering drops, length of therapeutic intraocular pressure reduction, and incidence of side effects commonly encountered with traditional laser trabeculoplasty including intraocular inflammation and intraocular pressure spikes.
Interventions
DEVICESelective Laser Trabeculoplasty
Sponsors
David Belyea
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
Yes
Inclusion criteria
* Patients of any ange age * Diagnosis of open angle glaucoma who have not had recent changes in their medication regimen.
Exclusion criteria
* Patients with active neovascularization of the angle, angle closure glaucoma, angle recession, or anterior uveitis
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intraocular Pressure Reduction | within 6 weeks to 3 months after the laser procedure is completed | evaluate the effectiveness of micropulse laser trabeculoplasty in intraocular pressure reduction in patients with open angle glaucoma as compared to conventional selective laser trabeculoplasty The aim of this study was to prospectively compare the efficacy, safety, and tolerability of selective laser trabeculoplasty (SLT) vs micropulse laser trabeculoplasty (MLT) in reducing intraocular pressure (IOP) in open-angle glaucoma patients. |
| Intraocular Pressure (IOP) Reduction Comparison Between MLT and SLT | 24-52 week interval | Intraocular pressure (IOP) reduction comparison between MLT and SLT |
| Intraocular Pressure (IOP) Reduction | 52 weeks | Percentage of participants with a decrease of greater or equal to 3 mmHg intraocular pressure from baseline |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty. | at the time of treatment and at 1 week following the laser procedure | The measurement of pain commonly encountered with traditional laser trabeculoplasty including intraocular inflammation will be measured and compared between both lasers (SLT vs. MLT). Standardized pain survey (scale of 0=none and 10=severe) Higher number, the more pain was being experienced by subject |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Micropulse Laser Trabeculoplasty Patient's randomized to MLT would be treated with the following settings: 300 micron spot size, 0.3 second duration, 15% duty cycle, and 1000 milliWatt power. They would be treated with confluent laser spots across the entire 360 degrees of the trabecular meshwork. Each patient would receive pre-treatment with a drop on iopidine or brimonidine to prevent post-operative intraocular pressure (IOP) spikes as per standard pre-laser trabeculoplasty protocol.
Micropulse Laser Trabeculoplasty | 38 |
| Selective Laser Trabeculoplasty (SLT) Patient's randomized to SLT would be treated with the following settings: 400 micron spot size, 0.3 second duration, and 1.00 milliWatt (mW) power. They would be treated with confluent laser spots across the entire 360 degrees of the trabecular meshwork. Each patient would receive pre-treatment with a drop on iopidine or brimonidine to prevent post-operative IOP spikes as per standard pre-laser trabeculoplasty protocol.
Selective Laser Trabeculoplasty | 31 |
| Total | 69 |
Baseline characteristics
| Characteristic | Selective Laser Trabeculoplasty (SLT) | Total | Micropulse Laser Trabeculoplasty |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 19 Participants | 37 Participants | 18 Participants |
| Age, Categorical Between 18 and 65 years | 12 Participants | 32 Participants | 20 Participants |
| Age, Continuous | 67.6 years STANDARD_DEVIATION 0.85 | 66.9 years STANDARD_DEVIATION 0.55 | 66.1 years STANDARD_DEVIATION 0.3 |
| Race and Ethnicity Not Collected | — | 0 Participants | — |
| Region of Enrollment United States | 31 participants | 69 participants | 38 participants |
| Sex: Female, Male Female | 19 Participants | 35 Participants | 16 Participants |
| Sex: Female, Male Male | 12 Participants | 34 Participants | 22 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 38 | 0 / 31 |
| other Total, other adverse events | 0 / 38 | 0 / 31 |
| serious Total, serious adverse events | 0 / 38 | 0 / 31 |
Outcome results
Primary
Intraocular Pressure (IOP) Reduction
Percentage of participants with a decrease of greater or equal to 3 mmHg intraocular pressure from baseline
Time frame: 52 weeks
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Micropulse Laser Trabeculoplasty | Intraocular Pressure (IOP) Reduction | 37 percentage of participants |
| Selective Laser Trabeculoplasty (SLT) | Intraocular Pressure (IOP) Reduction | 36 percentage of participants |
Primary
Intraocular Pressure (IOP) Reduction Comparison Between MLT and SLT
Intraocular pressure (IOP) reduction comparison between MLT and SLT
Time frame: 24-52 week interval
Population: A total of 69 patients with uncontrolled open-angle glaucoma were recruited, candidates with open-angle glaucoma on maximally tolerated medical therapy with the need for additional IOP lowering. All patients had only one eye included in the study.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Micropulse Laser Trabeculoplasty | Intraocular Pressure (IOP) Reduction Comparison Between MLT and SLT | 15.7 mmHg | Standard Deviation 0.2 |
| Selective Laser Trabeculoplasty (SLT) | Intraocular Pressure (IOP) Reduction Comparison Between MLT and SLT | 14.35 mmHg | Standard Deviation 0.3 |
Primary
Intraocular Pressure Reduction
evaluate the effectiveness of micropulse laser trabeculoplasty in intraocular pressure reduction in patients with open angle glaucoma as compared to conventional selective laser trabeculoplasty The aim of this study was to prospectively compare the efficacy, safety, and tolerability of selective laser trabeculoplasty (SLT) vs micropulse laser trabeculoplasty (MLT) in reducing intraocular pressure (IOP) in open-angle glaucoma patients.
Time frame: within 6 weeks to 3 months after the laser procedure is completed
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Micropulse Laser Trabeculoplasty | Intraocular Pressure Reduction | 17.01 percentage change | Standard Error 1 |
| Selective Laser Trabeculoplasty (SLT) | Intraocular Pressure Reduction | 14.29 percentage change | Standard Error 1 |
Secondary
Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty.
The measurement of pain commonly encountered with traditional laser trabeculoplasty including intraocular inflammation will be measured and compared between both lasers (SLT vs. MLT). Standardized pain survey (scale of 0=none and 10=severe) Higher number, the more pain was being experienced by subject
Time frame: at the time of treatment and at 1 week following the laser procedure
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Micropulse Laser Trabeculoplasty | Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty. | During Treatment | 1.34 score on a scale |
| Micropulse Laser Trabeculoplasty | Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty. | 1 Week Post Treatment | 0.89 score on a scale |
| Selective Laser Trabeculoplasty (SLT) | Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty. | During Treatment | 2.83 score on a scale |
| Selective Laser Trabeculoplasty (SLT) | Measurement of Pain/Inflammation by a Pain Scale Post Laser Treatments From Micropulse and Selective Laser Trabeculoplasty. | 1 Week Post Treatment | 2.81 score on a scale |