Two Patterns of Micropulse Laser in the Treatment of Chronic Central Serous Chorioretinopathy

Study Overview
=================
Brief Summary
-----------------
Central serous chorioretinopathy (CSC) is a common eye disease mainly involving the macular area, causing central visual acuity loss. Recently, subthreshold micropulse laser used in treating chronic CSC is proved to be safe and effective. However, some studies indicate that it's less effective than half dose photodynamic therapy (PDT). Certain physicians, including us, think that this may be related to micropulse laser parameters. Thus we need to explore better laser patterns to replace PDT in treating chronic CSC. The aim of this study is to compare the treatment effect of two different patterns of laser parameters (small and regular spot diameter) in treating chronic CSC. In this randomized, double blinded, controlled trial, by comparing the subretinal fluid regression ratio, central retinal thickness, macular microvisual field, macular vascular density, chroidal volume changes and visual acuity of two groups 6 months after micropulse laser treatment, we aim to evaluate the safety and efficacy of refined micropulse laser in treating chronic CSC.

Official Title
-----------------
A Randomized Controlled Study of Two Patterns of Micropulse Laser in the Treatment of Chronic Central Serous Chorioretinopathy

Conditions
-----------------
Central Serous Chorioretinopathy

Intervention / Treatment
-----------------
* Procedure: 100μm laser spot diameter micropulse laser
* Procedure: 200μm laser spot diameter micropulse laser


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients age range 18-50 years Patients diagnosed with chronic Central serous chorioretinopathy Patients have signed informed consent Exclusion Criteria: A history of other fundus diseases or refractive media opacity Patients have underwent other treatment methods for chronic Central serous chorioretinopathy Diopter>-6D A history of system diseases such as hypertension or diabetes A history of using local or systemic corticosteroids

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 100μm laser spot diameter group<br> | Procedure: 100μm laser spot diameter micropulse laser<br>* 100μm laser spot diameter micropulse laser at baseline, then follow-up for 6 months<br>|
| Active Comparator: 200μm laser spot diameter group<br> | Procedure: 200μm laser spot diameter micropulse laser<br>* 200μm laser spot diameter micropulse laser at baseline, then follow-up for 6 months<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subretinal fluid regression ratio | Comparing the subretinal fluid regression ratio of two groups at 6 months follow-up | 6 months | 
| Central retinal thickness changes | Comparing the central retinal thickness changes of two groups at 6 months | 6 months |