Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

No abstract

Optical coherence tomography angiography clearly delineated the retinal microcirculation and allowed quantification of vascular perfusion of each layer. As diabetic retinopathy progressed, a decrease in perfusion index is more pronounced in the deep retinal plexus and precedes changes in superficial plexus.

Optical coherence tomography (OCT) was introduced about two decades ago and has revolutionized ophthalmic practice in recent years. It is a noninvasive noncontact imaging modality that provides a high-resolution cross-sectional image of the cornea, retina, choroid and optic nerve head, analogous to that of the histological section. Advances in OCT technology in signal detection technique from time-domain (TD) to spectral-domain (SD) detection have given us the potential to study various retinal layers more precisely and in less time. SD-OCT better delineates structural changes and fine lesions in the individual retinal layers. Thus, we have gained substantial information about the pathologic and structural changes in ocular conditions with primary or secondary retinal involvement. This review we discuss the clinical application of currently available SD-OCT in various retinal pathologies. Furthermore, highlights the benefits of SD-OCT over TD. With the introduction of enhanced depth imaging and swept – source OCT visualization of the choroid and choriocapillaris has become possible. Therefore, OCT has become an indispensable ancillary test in the diagnosis and management of diseases involving the retina and/or the choroid. As OCT technology continues to develop further it will provide new insights into the retinal and choroidal structure and the pathogenesis of posterior segment of the eye.

We are presenting the initial results of inverted internal limiting membrane (ILM) flap technique for large macular hole. Five eyes of five patients with large diameter macular hole (>700 μm) were selected. All patients underwent inverted ILM flap technique for macular hole. Anatomical closure and functional success were achieved in all patients. There was no loss of best-corrected visual acuity in any of the patients. Inverted ILM flap technique in macular hole surgery seems to have a better hole closure rates, especially in large diameter macular holes. Larger case series is required to assess the efficacy and safety of this technique.

SSFIOLs are effective in correcting aphakia in children; long-term follow-up of these children is, however, necessary.

GeTe is among the most fascinating inorganic compounds for thermoelectric (TE) conversion of waste heat into electricity. However, TE performance in its ambient rhombohedral phase is strongly impeded by natural...

Purpose: The aim of this study was to examine the hyperreflective dots seen in choroid on spectral domain optical coherence tomography (SDOCT) in eyes with diabetic macular edema (DME) and correlate it with visual acuity. Design: Consecutive, cross-sectional case series of patients with DME between January 2017 and December 2017. Methods: Eyes with DME having central foveal thickness ≥250 μm were included. SDOCT was performed using Spectralis system (Heidelberg Engineering, Germany). Hyperreflective choroidal foci (HCF) were defined as well-circumscribed dots within choroid having reflectivity equal to or higher than adjacent retinal pigment epithelium. HCF were counted manually within 1500 μm of fovea using a horizontal line scan by a blinded observer. Eyes were divided in 3 groups: group A (no HCF), group B (1–10 HCF), and group C (>10 HCF). Results: One hundred nineteen eyes of 60 DME patients were included. Sixty (50.4%) eyes were in group A, whereas 42 (33.6%) and 17 (14.2%) eyes belonged to group B and group C, respectively. The mean logMAR best corrected visual acuity was significantly lower in group B (0.76 ± 0.79) and C (1.2 ± 0.78) as compared with group A (0.22 ± 0.49) ( P = 0.001). Mean central foveal thickness in group A (300.4 ± 122.4 μm) was significantly lower than group B (455.52 ± 209.1 μm) and group C (529.4 ± 196.4 μm) with P value of 0.001. Conclusions: The present study describes HCF as novel prognostic SDOCT biomarker in DME whose presence denotes poor visual acuity. Further longitudinal studies are required to substantiate our findings.