|Year : 2015 | Volume
| Issue : 12 | Page : 879-880
A Glimpse into this issue
Editor, Indian Journal of Ophthalmology, Chairman, Managing Director, Aditya Jyot Eye Hospital Pvt. Ltd., Wadala (W), Mumbai, Maharashtra, India
|Date of Web Publication||10-Feb-2016|
Editor, Indian Journal of Ophthalmology, Chairman, Managing Director, Aditya Jyot Eye Hospital Pvt. Ltd., Wadala (W), Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Natarajan S. A Glimpse into this issue. Indian J Ophthalmol 2015;63:879-80
This issue of IJO has some interesting articles on two conditions plaguing the Indian population, namely diabetes and age-related macular degeneration (AMD).
Diabetic retinopathy (DR) and diabetic macular edema (DME) are common sight-threatening retinopathies caused by abnormalities in retinal vessels and capillaries of diabetes patients. The choroid is an important vascular tissue that supplies blood to the outer retina, including the retinal pigment epithelium and photoreceptors.
A study conducted by Kim et al. concluded that choroidal thickness increased significantly as the severity worsened from mild/moderate nonproliferative DR to proliferative DR and decreased in panretinal photocoagulation (PRP)-treated eyes. The subfoveal choroid was thicker in eyes with DME than in those without and was thickest in eyes with subretinal detachment-type DME, whereas Regatieri et al. reported in 2012 that choroidal thickness decreases in eyes with DME and in eyes treated with scatter PRP. Previous studies demonstrated that choroidal blood flow markedly decreases after laser PRP, possibly due to the down regulation of vascular endothelial growth factor (VEGF)., It is thought that the choroidal layer becomes significantly thinner after PRP due to decreased blood flow and subsequent ischemic atrophic change.
In this issue, Sudhalkar et al. in their article, "Choroidal Thickness in Diabetics of Indian Ethnicity," have postulated that the choroidal thickness decreases progressively with increase in the severity of DR. Further, they re-iterate the studies conducted elsewhere in the world that choroidal thinning may contribute to the pathogenesis of the disease. They did not find any difference in the thickness of choroid between patients treated with laser and treatment naive patients.
AMD is the leading cause of blindness in older adults. Neovascular AMD is an advanced form of macular degeneration that historically has accounted for the majority of vision loss related to AMD. Sudhalkar et al. in their article, "AMD in India: 5-year analysis" have presented that the AMD patients in India present later in the course of the disease, but bilateral advanced AMD was uncommon. With newer diagnostic techniques, it is possible to detect this condition with great precision.
The macular angiography scan covers a 3 mm × 3 mm area and comprises 200 × 200 × 8 A-scans acquired in 3.5 s. Flow is detected using the split-spectrum amplitude de-correlation angiography algorithm. Motion artifacts are removed by three-dimensional (3D) orthogonal registration and merging of four scans. The 3D angiography is segmented into three layers: Inner retina (to show retinal vasculature), outer retina (to identify choroidal neovascularization), and choroid.
Optical coherence tomography (OCT) angiography provides a unique opportunity to study the morphology of occult Type 1 neovascular membranes in AMD and allows precise structural and vascular assessment noninvasively. Kuehlewein et al. identified a large mature neovascular complex in approximately 75% of eyes, typically consisting of a feeder vessel and large branching vessels resistant to anti-VEGF therapy  Jia et al. in their study showed sizes and locations that were confirmed by fluorescein angiography. OCT angiography provided more distinct vascular network patterns that were less obscured by subretinal hemorrhage.
Another interesting article in this issue by Shanmugam et al., "Effect of Lanosterol on Human Cataract Nucleus," refutes the findings of Zhao et al. on the effect of lanosterol on human cataract nucleus. It makes for interesting reading and probably more studies in the future. I hope you will make the most of reading this issue.
| References|| |
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Kim JT, Lee DH, Joe SG, Kim JG, Yoon YH. Changes in choroidal thickness in relation to the severity of retinopathy and macular edema in type 2 diabetic patients. Invest Ophthalmol Vis Sci 2013;54:3378-84.
Regatieri CV, Branchini L, Carmody J, Fujimoto JG, Duker JS. Choroidal thickness in patients with diabetic retinopathy analyzed by spectral-domain optical coherence tomography. Retina 2012;32:563-8.
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Optical coherence tomography angiography of type 1 neovascularization in age-related macular degeneration. Am J Ophthalmol 2015;160:739-48.e2.
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Zhao L, Chen XJ, Zhu J, Xi YB, Yang X, Hu LD, et al.
Lanosterol reverses protein aggregation in cataracts. Nature 2015;523:607-11.