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Retinal image analysis

Bright S Ashimatey, Brett J King, Victor E Malinovsky, William H Swanson
SIGNIFICANCE: Glaucomatous nasal visual field abnormalities correspond to damage in the temporal raphe-where individual nerve bundles can be visualized. The ability to quantify structural abnormality in the raphe, with a clinically applicable protocol, sets the stage for investigating the raphe as a potential site for assessing early glaucoma. PURPOSE: To develop a clinically applicable imaging and analysis technique for identifying retinal nerve fiber bundle abnormalities in the temporal raphe...
March 21, 2018: Optometry and Vision Science: Official Publication of the American Academy of Optometry
Jennifer I Lim, Dingcai Cao
PURPOSE: To determine whether the retina is thinner in sickle cell patients than in race- and age-matched controls, and if it is thinner, whether there is any association with systemic diseases. METHODS: Sickle cell and control (age- and race-matched) patients were prospectively enrolled from a university retina clinic into this observational study. Participants underwent visual acuity testing, slit-lamp biomicroscopy, dilated ophthalmoscopy, and spectral domain optical coherence tomography imaging...
March 16, 2018: American Journal of Ophthalmology
Salomon Y Cohen, Alexandra Miere, Sylvia Nghiem-Buffet, Franck Fajnkuchen, Eric H Souied, Sarah Mrejen
A review of the literature from 2014 to 2016 was conducted, focusing on the results of optical coherence tomography angiography in different chorioretinal diseases. In only 3 years, optical coherence tomography angiography has been shown to be an effective tool for diagnosing choroidal neovascularization complicating age-related macular degeneration, pathologic myopia, and inflammatory conditions. The technique has sometimes been considered superior to conventional multimodal imaging, for example, in choroidal neovascularization associated with chronic central serous chorioretinopathy or multifocal choroiditis...
March 1, 2018: European Journal of Ophthalmology
Rohan Chawla, Amar Pujari, Kanhaiya Mittal, Vaishali Rakheja, Ashish Markan
Swept-source optical coherence tomography angiography (SS-OCTA) is a promising new imaging modality for assessing retinal and choroidal vasculature. Faster scanning speed, large number of A-scan acquisition, and enhanced depth penetration has enhanced the detailed analysis of retinal layers. The authors discuss SS-OCTA features of a rare case of retinal arteriovenous malformation. Image analysis revealed the anomalous large-caliber vessels occupying up to the entire retinal thickness with associated echolucent changes in the inner retinal layers surrounding the retinal vessels, along with disruption of the outer retinal layers, including the inner/outer segments of photoreceptors beneath the large tortuous vessels outside the foveola in absence of any capillary nonperfusion areas or lack of significant macular edema...
March 1, 2018: Ophthalmic Surgery, Lasers & Imaging Retina
Efrat Fleissig, Mor Pavlovksy, Anat Loewenstein, Dinah Zur, Hadas Newman, Shay Keren, Dafna Goldenberg, Efrat Bar-Ilan, Michaella Goldstein
PURPOSE: To investigate ocular manifestations in patients with vitiligo by multimodal imaging, including optical coherence tomography (OCT), color fundus photography, and fundus autofluorescence (FAF). METHODS: In this prospective, observational clinical study, vitiligo patients underwent ophthalmologic and dermatologic clinical assessment and imaging by spectral-domain OCT, FAF, and color fundus imaging. Ocular echography was performed as indicated. Statistical analysis was performed using paired T test and Pearson correlation...
March 16, 2018: Graefe's Archive for Clinical and Experimental Ophthalmology
Jonathan Krause, Varun Gulshan, Ehsan Rahimy, Peter Karth, Kasumi Widner, Greg S Corrado, Lily Peng, Dale R Webster
PURPOSE: Use adjudication to quantify errors in diabetic retinopathy (DR) grading based on individual graders and majority decision, and to train an improved automated algorithm for DR grading. DESIGN: Retrospective analysis. PARTICIPANTS: Retinal fundus images from DR screening programs. METHODS: Images were each graded by the algorithm, U.S. board-certified ophthalmologists, and retinal specialists. The adjudicated consensus of the retinal specialists served as the reference standard...
March 2, 2018: Ophthalmology
Kyoung Min Lee, Ho-Kyung Choung, Martha Kim, Sohee Oh, Seok Hwan Kim
PURPOSE: To investigate the positional change of central retinal vasculature and vascular trunk to deduce the change in the lamina cribrosa (LC) during axial elongation. DESIGN: Prospective cohort study. PARTICIPANTS: Twenty-three healthy myopic children (46 eyes). METHODS: Participants had undergone a full ophthalmologic examination and axial length measurement every 6 months for 2 years. Using spectral-domain OCT, circle scans centered around the optic disc in the glaucoma progression analysis mode, which enabled capturing of the same positions throughout the entire study period, and enhanced depth imaging of the deep optic nerve head complex were performed...
March 12, 2018: Ophthalmology
Rashmi Panda, N B Puhan, Aparna Rao, Debananda Padhy, Ganapati Panda
Retinal nerve fiber layer defect (RNFLD) provides an early objective evidence of structural changes in glaucoma. RNFLD detection is currently carried out using imaging modalities like OCT and GDx which are expensive for routine practice. In this regard, we propose a novel automatic method for RNFLD detection and angular width quantification using cost effective redfree fundus images to be practically useful for computer-assisted glaucoma risk assessment. After blood vessel inpainting and CLAHE based contrast enhancement, the initial boundary pixels are identified by local minima analysis of the 1-D intensity profiles on concentric circles...
March 6, 2018: Computerized Medical Imaging and Graphics: the Official Journal of the Computerized Medical Imaging Society
Fantin Girard, Conrad Kavalec, Farida Cheriet
Optic disc (OD) appearance in fundus images is one of the clinical indicators considered in the assessment of retinal diseases such as glaucoma. The cup-to-disc ratio (CDR) is the most common clinical measurement used to characterize glaucoma. However, the CDR only evaluates the relative sizes of the cup and the OD via their diameters. We propose to construct an atlas-based shape descriptor (ASD) to statistically characterize the geometric deformations of the OD shape and of the blood vessels' configuration inside the OD region...
January 2018: Journal of Medical Imaging
Ivan Bozic, Xiaoyue Li, Yuankai Tao
The zebrafish is a robust model for studying human ophthalmic function and disease because of its fecundity, life-cycle, and similarities between its retinal structure and the human retina. Here, we demonstrate longitudinal in vivo imaging of retinal structure using optical coherence tomography (OCT) and noninvasive retinal vascular perfusion imaging using OCT angiography (OCT-A) in zebrafish. In addition, we present methods for retinal vascular segmentation and biometry to quantify vessel branch length, curvature, and angle...
March 1, 2018: Biomedical Optics Express
Kai Yu, Fei Shi, Enting Gao, Weifang Zhu, Haoyu Chen, Xinjian Chen
Optic nerve head (ONH) is a crucial region for glaucoma detection and tracking based on spectral domain optical coherence tomography (SD-OCT) images. In this region, the existence of a "hole" structure makes retinal layer segmentation and analysis very challenging. To improve retinal layer segmentation, we propose a 3D method for ONH centered SD-OCT image segmentation, which is based on a modified graph search algorithm with a shared-hole and locally adaptive constraints. With the proposed method, both the optic disc boundary and nine retinal surfaces can be accurately segmented in SD-OCT images...
March 1, 2018: Biomedical Optics Express
Mohammad Idrees Adhi, Sumbul Kashif, Kashif Muhammed, Nisar Siyal
OBJECTIVE: To document clinical pattern of retinoblastoma in Pakistani population. METHODS: This retrospective study, which was conducted at Department of Ophthalmology, Dow University of Health Sciences, Karachi, reviewed clinical records of patients with retinoblastoma from 1997 to 2012. Staging of disease was done by referring to retinal diagrams, RetCam images, and first magnetic resonance imaging. Ophthalmic notes, imaging reports and histopathology reports of enucleated eyes established optic nerve involvement...
March 2018: JPMA. the Journal of the Pakistan Medical Association
Eric W Schneider, Samuel C Fowler
PURPOSE OF REVIEW: Optical coherence tomography angiography (OCT-A) provides rapid, flow-based imaging of the retinal and choroidal vasculature in a noninvasive manner. This review contrasts this novel technique with conventional angiography and discusses its current uses and limitations in the management of age-related macular degeneration (AMD). RECENT FINDINGS: Initial work with OCT-A has focused on its ability to identify choriocapillaris flow alterations in dry AMD and to sensitively detect choroidal neovascular membranes (CNVs) in neovascular AMD...
March 13, 2018: Current Opinion in Ophthalmology
Morteza Modarresi Asem, Iman Sheikh Oveisi, Mona Janbozorgi
Retinal blood vessels indicate some serious health ramifications, such as cardiovascular disease and stroke. Thanks to modern imaging technology, high-resolution images provide detailed information to help analyze retinal vascular features before symptoms associated with such conditions fully develop. Additionally, these retinal images can be used by ophthalmologists to facilitate diagnosis and the procedures of eye surgery. A fuzzy noise reduction algorithm was employed to enhance color images corrupted by Gaussian noise...
July 2018: Journal of Medical Imaging
F E Sahin, A R Tanguay
An imaging system design procedure for miniature wide-angle computational cameras with subsequent software correction of distortion is described. Such miniature wide-angle computational cameras have a broad range of applications, including eye-tracked extraocular cameras for retinal prostheses, and also wearable visual aids for the blind and those with low vision. As significant (typically barrel) distortion is commonplace in wide-field-of-view imaging systems, digital post-processing is often employed to generate rectilinear output images...
March 5, 2018: Optics Express
Mrinali P Gupta, Eliot Dow, Karen W Jeng-Miller, Shizuo Mukai, Anton Orlin, Kunyong Xu, Yoshihiro Yonekawa, R V Paul Chan
PURPOSE: To evaluate microstructural retinal abnormalities on spectral domain optical coherence tomography (SD-OCT) imaging of eyes with Coats disease. METHODS: This is a multicenter, retrospective study in which SD-OCT images of patients with treatment-naive Coats disease were correlated with clinical examination and visual acuity and, when available, followed longitudinally over time. RESULTS: Macular SD-OCT of 27 eyes with Coats disease revealed intraretinal edema (59%), intraretinal exudates (67%), subretinal fluid (37%), subretinal exudate (48%), ellipsoid zone disruption (52%), external limiting membrane disruption (41%), and subfoveal nodule (26%)...
March 8, 2018: Retina
Gözde Hondur, Emre Göktaş, Lama Al-Aswad, Gülgün Tezel
Purpose: This pilot cross-sectional study aimed to determine age-related changes of the retinal nerve fiber layer (RNFL) thickness in retinal periphery by swept-source optical coherence tomography-based analysis. Methods: Forty eyes of 40 healthy subjects were studied in three age groups, group 1 (20-40 years, n=15), group 2 (41-60 years, n=14), and group 3 (≥61 years, n=11). Wide-angle swept-source optical coherence tomography scans, including the optic disc and macula, were montaged with the nasal peripheral optical coherence tomography images acquired with a contralateral gaze...
2018: Clinical Ophthalmology
Ramachandran Rajalakshmi, Radhakrishnan Subashini, Ranjit Mohan Anjana, Viswanathan Mohan
OBJECTIVES: To assess the role of artificial intelligence (AI)-based automated software for detection of diabetic retinopathy (DR) and sight-threatening DR (STDR) by fundus photography taken using a smartphone-based device and validate it against ophthalmologist's grading. METHODS: Three hundred and one patients with type 2 diabetes underwent retinal photography with Remidio 'Fundus on phone' (FOP), a smartphone-based device, at a tertiary care diabetes centre in India...
March 9, 2018: Eye
Satoshi Katagiri, Shin Tanaka, Tadashi Yokoi, Takaaki Hayashi, Emiko Matsuzaka, Kazuko Ueda, Tomoyo Yoshida-Uemura, Akira Arakawa, Sachiko Nishina, Kazuaki Kadonosono, Noriyuki Azuma
Purpose: To report the clinical and genetic findings of a male toddler who presented bilateral bullous retinoschisis with a novel RS1 mutation. Observations: This is an observational case report of a patient referred to our hospital with esotropia. A comprehensive ophthalmic examination was performed with the boy (age, 1 year 4 months) under general anesthesia that included fundus examinations, fluorescein angiography (FA), swept-source optical coherence tomography (SS-OCT), and full-field electroretinography (FF-ERG)...
April 2017: American Journal of Ophthalmology Case Reports
Javier Mazzaferri, Bruno Larrivée, Bertan Cakir, Przemyslaw Sapieha, Santiago Costantino
Preclinical studies of vascular retinal diseases rely on the assessment of developmental dystrophies in the oxygen induced retinopathy rodent model. The quantification of vessel tufts and avascular regions is typically computed manually from flat mounted retinas imaged using fluorescent probes that highlight the vascular network. Such manual measurements are time-consuming and hampered by user variability and bias, thus a rapid and objective method is needed. Here, we introduce a machine learning approach to segment and characterize vascular tufts, delineate the whole vasculature network, and identify and analyze avascular regions...
March 2, 2018: Scientific Reports
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