Quantitative spectral domain optical coherence tomography thickness parameters in type II diabetes

Purpose: To elucidate the changes in retinal thickness and individual layer thickness in subjects with diabetic retinopathy (DR) using spectral domain optical coherence tomography (SDOCT). Materials and Methods: A total of 251 eyes from 170 subjects were included in this study. The study sample was subdivided into nondiabetic subjects; subjects with diabetes but no DR; subjects with mild, moderate, and severe nonproliferative DR (NPDR); and proliferative DR. Various retinal thickness parameters were assessed using SDOCT. Results: The mean age of the study population was 55.34 ± 9.02 years (range: 32-80 years) and 56.6% of the subjects were males. Men had significantly greater central foveal thickness, central subfield thickness, retinal nerve fiber layer thickness, and retinal thickness in all the quadrants of 3 mm and 6 mm zones compared to women (P < 0.001). Superior (293.11 ± 25.46 vs. 285.25 ± 19.17; P = 0.044) and temporal (282.10 ± 25.26 vs. 272.46 ± 16.21; P = 0.011) quadrants showed an increased retinal thickness in any DR group when compared with diabetic subjects without DR. Photoreceptor layer thickness was significantly reduced in diabetic subjects with no DR when compared with nondiabetic subjects and also in cases of severe NPDR when compared with mild and moderate NPDR. Conclusion: Here, we analyze the quantitative retinal thickness parameters in diabetic subjects using SDOCT. Neuronal degenerative changes such as photoreceptor and retinal pigment epithelial thinning in case of DR are also reported

Retinal sensitivity in healthy Indians using microperimeter

Aims: To establish the retinal sensitivity values in healthy Indians using microperimeter. Materials and Methods: In this prospective study, 144 healthy volunteers were included. All the participants underwent a comprehensive ophthalmic examination including contrast sensitivity. Microperimetry was performed in the central 20° of the macula using 76 stimulus points to assess the retinal sensitivity, and the fixation characteristics in the study population were assessed. Results: The mean age of the study sample was 43.08 ± 10.85 years (range: 25-69). Mean retinal sensitivity was 18.26 ± 0.99 dB. Males had significantly increased retinal sensitivity (18.34 vs. 18.17 dB, P = 0.03). The linear regression analysis revealed a 0.04 dB per year age-related decline in mean retinal sensitivity. Contrast sensitivity was significantly correlated with the mean retinal sensitivity (r = 0.432, P < 0.001). Fixation stability in the central 2° and 4° were 69% and 89%, respectively. Conclusion: Microperimeter is an ideal tool to assess the retinal sensitivity and the fixation behavior. These normative values could help in drawing a meaningful conclusion in various retinal pathologies

Congenital preretinal arterial loop: Is it a misnomer?

We describe a case of recurrent spontaneous vitreous haemorrhage due to congenital retinal arterial loop. The pre-optical coherence tomography showed the loop to be intraretinal rather than pre retinal. Thus the term pre retinal arterial loop is a misnomer. The arterial loop is in the superficial layer of retinal nerve fiber layer. We also demonstrated preretinal posterior hyaloid tissue attached on the retinal arterial loop, which may be the cause of traction and spontaneous recurrent VH

Diabetic retinopathy: An epidemic at home and around the world

Prevention of blindness due to diabetic retinopathy (DR) requires effective screening strategies, for which eye care providers need to know the magnitude of the burden and the risk factors pertinent in their geographical location. It is estimated that around 72 million of the global adult population (around 8.2%) has diabetes and about one-fifth of all adults with diabetes lives in the South-East Asia. In India, around 65 million people have diabetes. As the global prevalence of diabetes increases, so will the number of people with diabetes-related complications, such as DR; nearly one-third of them are likely to develop this complication. This article reviews the present status of diabetes and DR in India, the current situation of DR services and the projections on the load of morbidity associated with retinopathy. The article compiles the Indian studies elucidating the risk factors for DR

Spectral domain optical coherence tomography characteristics in diabetic retinopathy

Purpose: To report the appearance of diabetic retinopathy lesions using spectral domain optical coherence tomography (SD-OCT). Materials and Methods: A total of 287 eyes of 199 subjects were included. All the subjects underwent complete ophthalmic examination including SD-OCT. Results: The appearance of various lesions of diabetic retinopathy and the retinal layers involved were reported. In subjects with macular edema the prevalence of incomplete PVD was 55.6%. Conclusion: SD-OCT brings new insights into the morphological changes of the retina in diabetic retinopathy

Spectral domain optical coherence tomography and microperimetry in foveal hypoplasia

A case of foveal hypoplasia associated with ocular albinism with anatomic and functional changes by various techniques using spectral domain optical coherence tomography (SD-OCT), microperimeter and confocal scanning laser ophthalmoscope is described. This case highlights the importance of microperimeter in detecting the functional abnormalities of vision and SD-OCT in identifying the retinal laminar abnormalities in foveal hypoplasia

Foveal slope measurements in diabetic retinopathy: Can it predict development of sight-threatening retinopathy? Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SN-DREAMS II, Report no 8)

Aim: The aim was to assess the foveal slope configuration in subjects with type 2 diabetes in a population-based study. Materials and Methods: A subset of 668 subjects from Sankara Nethralaya Diabetic Retinopathy (DR) Epidemiology and Molecular Genetics Study II, a population-based study, were included in the current study. All the subjects underwent comprehensive ophthalmic evaluation including spectral domain optical coherence tomography. Foveal thickness was assessed in five central early treatment DR study quadrants from the three-dimensional scan and foveal slope was calculated in all the four quadrants. Results: Subjects with sight-threatening DR (STDR) had significantly shallow foveal slope in inferior quadrant (STDR: 7.33 ± 6.26 vs. controls: 10.31 ± 3.44; P = 0.021) when compared to controls and in superior (STDR: 7.62 ± 5.81 vs. no DR: 9.11 ± 2.82; P = 0.033), inferior (STDR: 7.33 ± 6.26 vs. no DR: 8.81 ± 2.81; P = 0.048), and temporal quadrants (STDR: 6.69 ± 5.70 vs. no DR: 7.97 ± 2.33; P = 0.030) when compared to subjects with no DR. Foveal slope was significantly shallow among the older age groups in subjects with no DR (P < 0.001) and non-STDR (P = 0.027). Average foveal slope in the diabetic subjects was independently and significantly correlated with increase in age (r = −0.241; P < 0.001) and central subfield thickness (r = −0.542; P < 0.001). Conclusion: Changes in foveal slope were seen with increasing age; however, in diabetes these segmental slope changes can be seen in late DR (STDR)

Impairment of Colour Vision in Diabetes with No Retinopathy: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SNDREAMS- II, Report 3).

To assess impairment of colour vision in type 2 diabetics with no diabetic retinopathy and elucidate associated risk factors in a population-based cross-sectional study.This is part of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular-genetics Study (SN-DREAMS II) which was conducted between 2007-2010. FM 100 hue-test was performed in 253 subjects with no clinical evidence of diabetic retinopathy. All subjects underwent detailed ophthalmic evaluation including cataract grading using LOCS III and 45° 4-field stereoscopic fundus photography. Various ocular and systemic risk factors for impairment of colour vision (ICV) were assessed in subjects with diabetes but no retinopathy. P value of < 0.05 was considered statistically significant.The mean age of the study sample was 57.08 ± 9.21 (range: 44-86 years). Gender adjusted prevalence of ICV among subjects with diabetes with no retinopathy was 39.5% (CI: 33.5-45.5). The mean total error score in the study sample was 197.77 ± 100 (range: 19-583). The risk factors for ICV in the study were women OR: 1.79 (1.00-3.18), increased resting heart rate OR: 1.04 (1.01-1.07) and increased intraocular pressure OR: 1.12 (1.00-1.24). Significant protective factor was serum high-density lipoprotein OR: 0.96 (0.93-0.99).Acquired ICV is an early indicator of neurodegenerative changes in the retina. ICV found in diabetic subjects without retinopathy may be of non-vascular etiology