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Membrane removal in proliferative vitreoretinopathy
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
Michael S L.e.e, Gary W Abrams
Early investigators suggested that the cellular basis of PVR is the result of proliferating retinal pigment epithelial (RPE) cells, as well as retinal glial cells.3–;8 RPE cells have been identified by both light and electron microscopy on the retinal surface of longstanding detachments. Although the majority of the cells appear to be normal RPE cells, some RPE cells have undergone metaplastic differentiation into macrophage-like cells with phagocytic activity and others have undergone a second transformation into fibrocyte-like cells with collagen-producing ability.6 Retinal glial cells, which probably originate from Müller cells, can proliferate and break through the internal and external limiting membrane, forming epiretinal as well as subretinal membranes.4,7
Level Set Methods in Segmentation of SDOCT Retinal Images
Published in Ayman El-Baz, Jasjit S. Suri, Level Set Method in Medical Imaging Segmentation, 2019
N Padmasini, R Umamaheswari, Yacin Sikkandar Mohamed, Manavi D Sindal
As shown in Figure 5.2, the retina is a ten layered structure, viz., Nerve fiber layer (NFL), Ganglion cell layer (GCL), Inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), External limiting membrane (ELM), Ellipsoid zone (previously referred to as the IS/OS junction), Interdigitation zone, and Retinal pigment epithelium (RPE). Automatic detection of diabetic maculopathy from SDOCT retinal images is extremely important in analyzing the stage of diabetic retinopathy. Diabetic maculopathy is the condition of fluid being accumulated in between the retinal layers. As shown in Figure 5.3, SDOCT images provide more details about the intraretinal fluid and subretinal fluid present in the macula scan images.
Specific Synonyms
Published in Terence R. Anthoney, Neuroanatomy and the Neurologic Exam, 2017
External limiting membrane (C&S. p. 145, 147) Superficial glial membrane (ibid.)
Multiple Evanescent White Dot Syndrome Following Adenovirus Vector-Based COVID-19 Vaccine (Covishield)
Published in Ocular Immunology and Inflammation, 2023
Abhilasha Baharani, Raja Rami Reddy
On ophthalmic examination, her best corrected visual acuity (BCVA) was 20/20 (OD) and 20/32 (OS). Her intraocular pressures were 19 mm Hg (OD) and 16 mm Hg (OS). Anterior segment examination was unremarkable. Right eye fundus was normal. Fundus examination of the left eye showed a mild vitreous haze. Multifocal yellowish-white, deep retinal, small and larger dots were seen in the posterior pole and extended beyond the arcades (Figure 1A). Fundus autofluorescence (FAF) showed multiple scattered hyperautofluorescent spots (Figure 1B). Swept-source optical coherence tomography (SS-OCT) showed disruptions in the outer retina involving the ellipsoid zone (EZ), interdigitation zone (IZ), and external limiting membrane (ELM). Hyperreflective dots were seen in the outer nuclear layer (ONL) (Figure 2A). Humphrey visual field (HVF) 30–2 of the left eye revealed a generalized reduction and paracentral islands of sensitivity loss (Figure 3A).
Unilateral Acute Idiopathic Maculopathy following Severe Acute Respiratory Syndrome Corona Virus (SARS-CoV-2) Infection
Published in Ocular Immunology and Inflammation, 2023
Ramesh Venkatesh, Nikitha Gurram Reddy, Pranjal Mishra, Aditi Gupta, Padmamalini Mahendradas, Naresh Kumar Yadav
On subsequent follow-up visit (i.e., on Day 7 post-presentation), his best-corrected visual acuity recorded was 20/20, N6. OCT showed restoration of BLD. Irregularity of the photoreceptor layer and hyper-reflective material with shadowing still persisted. At the final follow-up visit at 5 weeks post presentation, bacillary layer remained attached with minimal irregularity of the photoreceptor layer. Hyper-reflective pigment clumps with underlying shadowing were still noted. The external limiting membrane remained unaffected throughout the different stages of the disease. His final visual acuity recorded in the right eye was 20/20, N6. Fluorescein and indocyanine green angiography tests were repeated at each of these follow-up visits, which showed reduction in lesion size and leakage from the lesion (Figure 2). Informed consent form was obtained from the patient for utilization of case details and images for publication purpose.
OCT Imaging in Infants
Published in Seminars in Ophthalmology, 2022
Sushma Jayanna, Subhadra Jalali, Tapas R Padhi, Komal Agarwal, Jay Chhablani
Coats’ Disease is unilateral disease, predominantly in male characterized with telangiectasia and exudation in periphery and posterior pole. In advanced stages, exudative and tractional retinal detachment, fibrosis and epiretinal membrane are noted. In neonate’s exudation can be severe causing xanthochoria with Neovascularization of Iris(NVI).22 Retinoblastoma should always be considered as one of the differentials and has to be ruled out. OCT mainly helps in cases with macular involvement including intraretinal exudates, subfoveal exudation, neurosensory detachment, subretinal fibrosis, and foveal involvement in advanced cases of tractional detachment (Figure 5). It also helps in monitoring responses to various treatment like anti-Vascular endothelial growth factor (VEGF), cryotherapy and laser photocoagulation. In later stages, outer retinal changes such as photoreceptor layer and external limiting membrane loss and foveal thinning can also be noted.23,24