Micropulse 577nm Laser vs Traditional Laser Treatment in Central Serous Chorioretinopathy

Study Overview
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Brief Summary
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The purpose of this study is to observe whether micropulse laser (MPL) is noninferiority to traditional laser therapy in central serous chorioretinopathy.

Detailed Description
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Central serous chorioretinopathy (CSC) is characterized by serous detachment of neurosensory retina which can cause lose in visual acuity. Some studies have shown that traditional laser treatment (TLT) is effective on CSC, although accompanied with side-effects, such as scar. Recent retrospective studies suggest micropulse laser (MPL) therapy may also be effective without obvious complications in this disease. But to date, there is no study on effectiveness of CSC between TLT and MPL. The study is the first prospective randomized controlled trial about 577nm micropulse laser versus traditional laser treatment in central serous chorioretinopathy. It is a noninferiority study. The investigators hypothesize that application of 577nm micropulse laser in patients with CSC will prompt resolution of CSC as measured by ocular coherence tomography and best corrected visual acuity.This will be a pilot study to establish sound methods and provide some insights to the safety and efficacy of CSC treatment. The primary outcome measures is the change of BCVA in 12 week.

Official Title
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A Prospective Non-inferiority Study of the Use of Micropulse 577nm Laser vs Traditional Laser Treatment in Central Serous Chorioretinopathy

Conditions
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Central Serous Choroidopathy

Intervention / Treatment
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* Device: 577-MPL
* Device: TLT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with CSC； age>=18 years old; Duration is less than 6 months； the presence of subretinal fluid(SRF) involving the macula and detected by use of optical coherence tomography (OCT), and CRT>=250um; active leakage located at ring 2 and ring 3 (ETDRS rings) on fluorescein angiography (FA). Exclusion Criteria: Patients with no case of CSC； Patients with other macular comorbidities including but not limited to diabetic retinopathy, macular degeneration； Patients with prior retinal treatment less than 3 months； Inability to obtain photographs or to perform FA

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 577-MPL<br>577nm subthreshold micropulse laser(577-MPL) will be performed on the areas identified on hyperfluorescent hot spots on the mid-phase (3 minutes) fluorescein. Multiple laser spots will be applied, covering the leakage area. Retreatment will be given in 12 weeks If SRF is not completely absorbed and CRT>= 250um. | Device: 577-MPL<br>* 9 spots multispot micropulse mode(without spacing between the spots),160 um spot size, 0.2 second duration, 5% duty cycle(ON time 0.1ms + OFF time 1.9ms), and 250 400 milliWatts of power(50% threshold power),150 200 spots, the laser area is the corresponding leakage on mid-phase FA and around leakage.<br>|
| Active Comparator: TLT<br>Traditional laser will be performed of the areas identified on hyperfluorescent hot spots on the mid-phase (3 minutes) fluorescein.Traditional laser spots will be applied, covering the leakage area. Retreatment will be given in 12 weeks If SRF is not completely absorbed and CRT>= 250um. | Device: TLT<br>* contimuous wave,100um spot size, 0.05 seconds duration, 55 60 milliwatts of power, 18 27 spots,the laser area is the corresponding leakage on mid-phase FA.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of Best Corrected Visual Acuity (BCVA) | ETDRS BCVA | 12 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the number of patients without any subretinal fluid (SRF) | SRF | 3 week, 7 week, 12 week | 
| Change of the central retinal thickness (CRT) | CRT | 3 week, 7 week, 12 week | 
| laser scar in area lasered on | colour image and OCT infared image | 12 week | 
| the number of patients need retreatment | PRN (pro re nata), only for SRF not completely absorbed and CRT >=250um | 12 week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Central Serous Choroidopathy, Micropulse Laser Treatment, Traditional laser Treatment, optical coherence tomography