Safety and Effectiveness Study of 532nm Laser Subthreshold Panretinal Photocoagulation for Severe NPDR

Study Overview
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Brief Summary
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This randomized, parallel controlled, clinical-trial aims to evaluate the therapeutic efficacy of 532nm laser partially subthreshold panretinal photocoagulation with PASCAL endpoint management function for severe non-proliferative diabetic retinopathy.

Detailed Description
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This randomized, parallel controlled, clinical-trial aims to evaluate the therapeutic efficacy of 532nm laser partially subthreshold panretinal photocoagulation with PASCAL endpoint management function for severe non-proliferative diabetic retinopathy : (1)To evaluate therapeutic effect of 532nm laser partially subthreshold panretinal photocoagulation with PASCAL endpoint management function for severe non-proliferative diabetic retinopathy; (2)To compare side effect of 532nm laser partially subthreshold panretinal photocoagulation with PASCAL endpoint management function on retina with traditional visible endpoint panretinal photocoagulation.

Official Title
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Randomized, Parallel Controlled, Clinical-trial on 532nm Laser Partially Subthreshold Panretinal Photocoagulation With PASCAL Endpoint Management Function for Severe Non-proliferative Diabetic Retinopathy(NPDR)

Conditions
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Severe Non-proliferative Diabetic Retinopathy

Intervention / Treatment
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* Radiation: T-PRP
* Radiation: S-PRP


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of severe non-proliferative diabetic retinopathy Age:45-80 years Best corrected visual acuity(BCVA) ≥20/100,Myopia≤-6 degree(-6D) No photocoagulation (PRP) before this clinical trial and no major ocular surgery (including cataract extraction, or any other intraocular surgery) within 3 months Ability and willingness to provide informed consent Exclusion Criteria: Participate in other clinical trials within 3 months Severe refractive media turbidity; Unable to accept laser treatment such as nystagmus, etc Medically or mentally unstable(including cardiovascular disorders, cerebrovascular diseases,liver and kidney disease,hematological disorder and psychosis Conditions that in the opinion of the investigator would interfere trial results or increase risk Conditions that in the opinion of the investigator would preclude participation in the study

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 80 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 |
| --- | --- |
| Active Comparator: T-PRP<br>532nm-short pulse panretinal photocoagulation with PASCAL function | Radiation: T-PRP<br>* 532nm-short pulse panretinal photocoagulation with PASCAL function<br>* Other names: Traditional-PRP;|
| Experimental: S-PRP<br>532nm-partially subthreshold short pulse panretinal photocoagulation with PASCAL endpoint management function | Radiation: S-PRP<br>* 532nm-partially subthreshold short pulse panretinal photocoagulation with PASCAL endpoint management function<br>* Other names: Subthreshold PRP;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change of best corrected visual acuity | best corrected visual acuity | 1 year | 
| the probability of vitreous haemorrhage |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central Retinal Thickness |  | 1 year | 
| foveal volume of macula |  | 1 year | 
| amount of microaneurysms |  | 1 year | 
| amount of bard exudate |  | 1 year | 
| amount of retinal hemorrhage |  | 1 year | 
| amount and area of IRMA |  | 1 year | 
| amount of neovascularization |  | 1 year | 
| change of ischemia area |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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severe non-proliferative diabetic retinopathy, subthreshold, panretinal photocoagulation, PASCAL, endpoint management