The Analysis Of The Percentage Of Areas Of Laser Photocoagulation And The Efficacy Of Laser Treatment In Diabetic Retinopathy

Objective:Diabetic retinopathy (DR) is a major complication of diabetic patients and is one of the major diseases that can cause blindness. It is important to diagnose and treat DR in time. Laser treatment of DR is still the gold effect .This study is to evaluate the reliability of a software we developed, and using the software to find the percentage of areas of laser photocoagulation. We hope to find a reasonable area that can be useful to the treatment of laser in DR.Method:Sixty eyes from 30 patients were enrolled with severe non-proliferative diabetic retinopathy and treated with laser photocoagulation. 48 eyes have no macular edema (ME), 12 eyes have macular edema. Those without ME were divided into A group (24 eyes) and B group (24 eyes), and those with ME divided into C (6 eyes) group and D group (6 eyes). A and C were treated with a distance of 1 laser spot between every two laser spots of PRP. B and D have a distance of 2 laser spot between two laser spot of prp. A and B were treated with PRP only. C and D were first treated with macular grid photocoagulation, then with PRP after 1 week. We analyse the thickness, volumn of macular and visual acutity (VA) after 3 months. Develop a computer image processing algorithm and software using Canny edge detector to process retinal fundus images and measure analyze the effect of laser treatment in terms of laser treating area and the ratio of this area and the overall retinal areas in FFA.Results:1. The areas of laser spot are 25%-40% if the distance between the 2 laser spot is 1 times of laser are 10%-25% if the distance between the 2 laser spot is 2 times of laser.2. There were no significant differences of VA and thickness and volume of macular between A group and B group before laser treatment (P >0.05), The same as C group and D group . There was no significant difference in VA between A group and B group after PRP (P >0.05). There was significant difference in VA between C group and D group after PRP, (P<0.05). There was no significant difference in thickness and volume of macular between A group and B group after PRP, (P >0.05). There was significant difference in thickness and volume of macular between C group and D group after PRP, (P<0.05).Conclusions:The areas of laser spot are 25%-40% if the distance between the 2 laser spot is 1 times of PRP treatment are 10%-25% if the distance between the 2 laser spot is 2 times. The areas of laser spot are 25%-40% is better for the prognosis of thickness of macular , VA and volume of macular in ME.