A Clinico-Angiographical Correlation in Grading of Diabetic Retinopathy- A one year hospital based cross sectional study

Abstract

INTRODUCTION Diabetes is the commonest metabolic abnormality in the world.. Diabetic retinopathy is a common and specific microvascular complication of diabetes, and remains the leading cause of preventable blindness in working-aged people. Delay in treatment is the main reason for visual loss and is largely preventable with proper screening. Among several studies that have been conducted for establishing a safe, cost effective and highly sensitive method for diabetic retinopathy screening and early detection, not many have compared FFA with slit lamp biomicroscopy. AIMS AND OBJECTIVES 1. To establish a correlation between the findings of slit lamp ophthalmoscopy and fundus flourescein angiography in grading of diabetic retinopathy. 2. To study the association between duration of diabetes mellitus, blood pressure and glycosylated hemoglobin with severity of diabetic retinopathy. MATERIALS AND METHODS The present study was carried out as a one year cross sectional descriptive observational design between January 1, 2014 and December 31, 2014 at KLES Hospital and MRC. A total of 52diabetic patients (both T1DM and T2DM) with retinopathy changes were included. Participants with very hazy ocular media, with history of intravitreal injection or fundus laser photocoagulation were excluded. Informed consent were taken followed by relevant history, general physicalexamination, complete ophthalmic examination. Diabetic retinopathy grading was done by slit lamp ophthalmoscopy using a Volk Superfield NC lens by an expert ophthalmologist.. The retinopathies were documented in accordance with the modified ETDRS classification. Fundus flourescein angiography were performed and grading by both methods compared. RESULTS There were 52 patients included in our study. Mean age of participants in was 55.88 12.27 and out of the 52 participants, there were 29 males and 23 females with M:F ratio of 1.3 : 1. Our study included 9.8% mild NPDR, 35.3% moderate NPDR, 17.6% severe NPDR, 9.8% very severe NPDR, 16.7% early PDR and 10.8% high risk PDR. 28.3% participants had CSME. The mean at diagnosis of diabetes was 16.8 years for types 1 diabetics, and 48.610.2 years for type 2 diabetics. Mean duration of diabetic age was 10.375.94. The age at diagnosis was not significantly associated with the severity of retinopathy. The severity of retinopathy and the duration of diabetes was found to be statistically significant (p=0.001). There was clinically significant association between concomitant hypertension in patients and the severity of retinopathy (p=0.161). The mean of Glycosylated haemoglobin (HbA1c) in the study population was 8.73.+ 1.5 %There was noted a highly significant increasing trend of severity of retinopathy with raise in HbA1c (p<0.001). The severity of retinopathy was significantly associated with treatment by insulin (p=0.030) . Slit lamp biomicroscopy had an excellent agreement with flourescein angiography for grading of diabetic retinopathy (k= 0.836). The sensitivity of slit lamp ophthalmoscopy for grading of diabetic retinopathy was 89.7%. The sensitivity and specificity for detection of CSME by slit lamp ophthalmoscopy were 100% . CONCLUSION Diabetic age, hypertension and high HbA1c are clinically and statistically significant risk factors for diabetic retinopathy. Since there is excellent agreement of slit lamp ophthalmoscopy with fundus flourescein angiography in grading of diabetic retinopathy (k=0.836) findings of slit lamp ophthalmoscopy may be relied upon and need not be confirmed with fundus fluorescein angiography