Navigation Laser Versus Traditional Laser Photocoagulation for Mild Diabetic Macular Edema

Study Overview
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Brief Summary
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The aim of this study is to evaluate treatment effect and safety of navigation laser photocoagulation for mild diabetic macular edema compared with traditional laser.

Detailed Description
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navigation laser is a novel fundus imaging and laser treatment method that allows imaging (infrared, colour, fluorescein angiography) and integrated laser treatment of the retina. Besides documentation, precision,safety and patient comfort,the main theoretical advantages lie in retina navigation.This randomized, parallel controlled, clinical-trial aims to evaluate treatment effect and safety of navigation laser photocoagulation for mild diabetic macular edema compared with traditional laser. The primary outcome measures is the Best-corrected visual acuity (BCVA) of the participants at 1 year after treatment. Besides, the slit-lamp examination, tonometry, funduscopy, and OCT, FFA, ICGA examinations will also be compared between different groups to find the advantage of navigation laser .

Official Title
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Navigation Laser Versus Traditional Laser Photocoagulation for Mild Diabetic Macular Edema：A Prospective, Randomized, Paralleled Clinical Trial

Conditions
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Diabetic Macular Edema

Intervention / Treatment
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* Device: Navigation laser
* Device: Traditional laser


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged ≥18 years Diagnosed as diabetic retinopathy with Mild macular edema BCVA≥0.5 No macular laser coagulation or surgery or medicine therapy of macular edema within the last 6 months Exclusion Criteria: Blood glucose was not controlled steadily(HbA1cd≥10%) Accompanied with severe hypertension（BP≥180/110mmHg） Taking part in other clinical trial within 3 months Planning panretinal photocoagulation(PRP) within 3 months Performed cataract surgery in the last 3 months Accompanied with other retinal vascular disease that can lead to macular edema, for example branch retinal vein occlusion(BRVO),central retinal vein occlusion(CRVO) Accompanied with severe opacity of refractive media that maybe impact therapy and observation Accompanied with nystagmus Accompanied with some history that maybe interfere with result or increase the risk of patients

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Experimental: Navigation laser<br>Navigation laser photocoagulation treatment to the macular area of retinal thickening with a focal pattern and/or grid pattern | Device: Navigation laser<br>* Navigation laser device is a scanning slit-based instrument.before treatment the surgeon plan laser spots on the screen based on image(infrared, colour, fluorescein angiography)and then apply automated patterns and single spots as appropriate.the device will automatically carry out the plan.<br>* Other names: Navigation laser photocoagulation treatment;|
| Active Comparator: Traditional laser<br>Traditional laser photocoagulation treatment to the macular area of retinal thickening with a focal pattern and/or grid pattern | Device: Traditional laser<br>* Traditional laser is a slitlamp based instrument.Surgeon operate traditional laer device while watching Participant's image(infrared, colour, fluorescein angiography) and then manually aim at and trigger laser.<br>* Other names: Traditional laser photocoagulation treatment;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best corrected visual acuity | Best Corrected Visual Acuity will be measured by standard Early Treatment Diabetic Retinopathy Study (ETDRS) protocol | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Central Retinal Thickness | Central Retinal Thickness will be performed by optical coherence tomography(OCT) | 12 months | 
| 10°retinal sensitivity | Retinal sensitivity will be measured by microperimetry | 12 months | 
| treatment time | treatment time is time from laser treatment beginning to end | 1 hour | 
| Participants pain intensity | Participants pain intensity will be immediately measured by Visual Analogue Scale/Score （VAS）after treatment.The VAS is a straight horizontal line of fixed length（100 mm）. The ends are defined as the extreme limits of the parameter to be measured (pain) orientated from the left (0) to the right (100).The patient marks on the line the point that participants feel represents their perception of their current pain intensity.the VAS score is determined by measuring the distance (mm) on the 100mm line between the 0 anchor and the patient's mark, providing a range of scores from 0-100. A higher score indicates greater pain intensity.the following cut points on the pain VAS have been recommended: no pain (0-4 mm), mild pain(5-44 mm), moderate pain (45-74 mm), and severe pain (75-100 mm) . | 1 hour | 
| Number of laser spots within macular fovea | Number of laser spots within macular fovea will measured by foundus photograph | 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diabetic Macular Edema, navigation laser, laser photocoagulation