The Research Of Heidelberg Retinal Tomography In Macular Edema By Laser Photocoagulation

ObjectivesTo observe the e value of macular edema before and after photocoagulation usingthe Heidelberg Retinal Tomography(HRTⅡMEM). To analyse the differences of theaverage e value of different measurement radiuses, and compare the macular retinalthickness measured by OCT. Evaluate the value of HRTⅡin the follow-up ofmacular edema treatment in order to guide the clinical treatment effectively.Objects and MethodsThe test group contains 21 cases, 28 eyes, which had diabetic retinopathy or retinalvein occlusion with macular edema. The normal control group contains 24 cases, 31eyes.Measure the average e value of macula within a radius of 500um, 1000um, and1500urn to the fovea center. The patients in test group received examination includingthe general inspection, HRTⅡand OCT before and one month and three monthsafter macular grid photocoagulation. Doing the correlation analysis between macularretinal thickness within a radius of 500um measured by OCT and the e value of thesame filed. The decimal eyesight will be converted to Log MAR eyesight so as toanalysis the correlation with e value.Using the analysis of variance between the two groups, the coefficient of variationand correlation analysis as the statistical methods.Results1.The average e value in test group without treatment and the normal control groupwithin a radius of 500urn is 2.13±0.69 and 1.08±0.43 separately, there was significantdifferences between the two groups (P＜0.05), and the same result was found within aradius of 1000um and 1500urn (P＜0.05).2. The average e value of the radius of 500um before photocoagulation,1 monthand 3 months after treatment.was 2.13±0.69, 1.85±0.62,1.43±0.43 There wassignificant differences between the three groups (P＜0.05).,and the same result wasfound within a radius of 1000um and 1500um3. The average e value of the radius of 500um,1000um, 1500um beforephotocoagulation was 2.13±0.69, 1.89±0.45 and 1.88±0.42 separately, there was no significant differences between the three groups (P＞0.05). The coefficient of variation(CV) of the three radiuses was 32.4%, 23.7% and 22.6%. There were no significantdifferences of the e value among the three radius 1 month and 3 months aftertreatment. The coefficient of variation (CV) was nearly the same as before treatment.4. The average e value within a radius of 500um before, 1 month and 3 monthsafter treatment measured by HRTⅡMEM was positively correlated with the averageretinal thickness measured by OCT, the correlation was 0.667,0.549 and 0.515separately (P＜0.05).5. The e value before treatment was positively correlated with the eyesight of LogMAR, the correlation was 0.428 (P＜0.05). But there was no correlation between theeyesight after 1 month, 3 months.Conclusions1. The macular edema index can reflect the macular edema caused by diabeticretinopathy, vein occlusion and other diseases.2. The macular edema index -e value was effective in the follow-up of macularedema treatment, and could become a objective index. It had better correlation withthe macular retinal thickness measured by OCT.3. The e value with different measurement radius can reflect the normal macularand location of the edema macular. Also it can choose suitable measurement radiusaccording to location of the disease that want to research.