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Retinal Layers Changes in Human Preclinical and Early Clinical Diabetic Retinopathy Support Early Retinal Neuronal and Müller Cells Alterations  [PDF]
Stela Vujosevic,Edoardo Midena
Journal of Diabetes Research , 2013, DOI: 10.1155/2013/905058
Abstract: Purpose. To evaluate the changes in thickness of individual inner and outer macular and peripapillary retinal layers in diabetes. Methods. 124 subjects (124 eyes) were enrolled: 74 diabetics and 50 controls. Macular edema, proliferative diabetic retinopathy (DR), any intraocular treatment and refractive error diopters were the main exclusion criteria. Full ophthalmic examination, stereoscopic fundus photography, and spectral domain-OCT were performed. After automatic retinal segmentation (layering) in 5 layers, the thickness of each layer was calculated, and values compared among groups. Results. Thirty patients had no DR, 44 patients had non proliferative DR. A significant increase of inner plexiform and nuclear layers was found in DR eyes versus controls ( ). A significant decrease ( ) of retinal nerve fiber layer (RNFL) and at specific sites of retinal ganglion cell layer ( ) was documented in the macula. In the peripapillary area there were no differences between diabetics and controls. Conclusions. Decreased RNFL thickness and increased INL/OPL thickness in diabetics without DR or with initial DR suggest early alterations in the inner retina. On the contrary, the outer retina seems not to be affected at early stages of DM. Automatic intraretinal layering by SD-OCT may be a useful tool to diagnose and monitor early intraretinal changes in DR. 1. Introduction Diabetic retinopathy (DR) is the first cause of visual impairment and blindness in the adult working-age population [1]. For a long period of time, DR has been considered primarily a retinal microvascular disorder caused by the direct effects of hyperglycemia and by the metabolic pathways it activates [2]. Nevertheless, some recent studies have demonstrated that retinal neurodegeneration (the result of a negative balance between neurotoxic and neuroprotective factors) is present even before the development of clinically detectable microvascular damage. Retinal neurodegeneration may therefore represent an early event in the pathophysiology of DR and may anticipate the onset of microvascular changes [2–4]. The term neurodegeneration used in this paper encompasses pathologic phenomena affecting both the pure neuronal component and the glial one. The hypothesis according to which neurodegeneration precedes the vascular one is confirmed by some electrophysiological and psychophysical studies, which show that the alterations are present even before the microvascular damage becomes ophthalmoscopically or angiographically visible. Such retinal function alterations mainly consist in contrast sensitivity
Simple, Inexpensive Technique for High-Quality Smartphone Fundus Photography in Human and Animal Eyes  [PDF]
Luis J. Haddock,David Y. Kim,Shizuo Mukai
Journal of Ophthalmology , 2013, DOI: 10.1155/2013/518479
Abstract: Purpose. We describe in detail a relatively simple technique of fundus photography in human and rabbit eyes using a smartphone, an inexpensive app for the smartphone, and instruments that are readily available in an ophthalmic practice. Methods. Fundus images were captured with a smartphone and a 20D lens with or without a Koeppe lens. By using the coaxial light source of the phone, this system works as an indirect ophthalmoscope that creates a digital image of the fundus. The application whose software allows for independent control of focus, exposure, and light intensity during video filming was used. With this app, we recorded high-definition videos of the fundus and subsequently extracted high-quality, still images from the video clip. Results. The described technique of smartphone fundus photography was able to capture excellent high-quality fundus images in both children under anesthesia and in awake adults. Excellent images were acquired with the 20D lens alone in the clinic, and the addition of the Koeppe lens in the operating room resulted in the best quality images. Successful photodocumentation of rabbit fundus was achieved in control and experimental eyes. Conclusion. The currently described system was able to take consistently high-quality fundus photographs in patients and in animals using readily available instruments that are portable with simple power sources. It is relatively simple to master, is relatively inexpensive, and can take advantage of the expanding mobile-telephone networks for telemedicine. 1. Introduction The ever increasing popularity and availability of smartphones and the rapid advances in technology for capturing and sharing images with them have resulted in the expanding use of smartphones as a clinical-imaging device in ophthalmology. This application has been facilitated by the ease of use and portability of the smartphones and the already extensive mobile-phone networks, and it presents a unique opportunity for applications such as telemedicine and self-diagnosis [1]. Retinal photography (fundus photography) is an essential part of ophthalmology practice. Acquisition of high-quality fundus images requires a combination of appropriate optics and illumination usually in the form of a condensing lens and a coaxial light source [2]. This is part of the reason that a commercial fundus camera normally costs tens to hundreds of thousand dollars. We describe in detail a relatively simple technique of fundus photography in human and rabbit eyes using a smartphone, an inexpensive app for the smartphone, and instruments that
Prospective comparison of two methods of screening for diabetic retinopathy by nonmydriatic fundus camera
Pedro Romero-Aroca, Ramon Sagarra-Alamo, Josep Basora-Gallisa, et al
Clinical Ophthalmology , 2010, DOI: http://dx.doi.org/10.2147/OPTH.S14521
Abstract: ospective comparison of two methods of screening for diabetic retinopathy by nonmydriatic fundus camera Original Research (3251) Total Article Views Authors: Pedro Romero-Aroca, Ramon Sagarra-Alamo, Josep Basora-Gallisa, et al Published Date December 2010 Volume 2010:4 Pages 1481 - 1488 DOI: http://dx.doi.org/10.2147/OPTH.S14521 Pedro Romero-Aroca1, Ramon Sagarra-Alamo2, Josep Basora-Gallisa2, Teresa Basora-Gallisa2, Marc Baget-Bernaldiz2, Angel Bautista-Perez1 1Ophthalmology Service, Hospital Universitario Sant Joan, IISPV, Universidad Rovira I Virgili, 2Health Primary Care Region Reus-Priorat, Universidad Rovira I Virgili, Reus, Spain Purpose: To compare the results obtained by two screening techniques for diabetic retinopathy. Methods: Patients were assessed in two groups, according to whether the retinal images were analyzed by the general practitioner (Group 1) or by the ophthalmologist (Group 2) in a two-year prospective study using telemedicine. Results: The number of patients referred to the nonmydriatic fundus camera unit was higher in Group 1 than in Group 2 (63.80% versus 17.63%). Greater patient adherence was observed in Group 1 than in Group 2 when patients came to retinography (98.25% versus 87.52%). There were no significant differences in other technique variables. The prevalence of diabetic retinopathy was similar in both groups (8.98% in Group 1 and 9.16% in Group 2), but the prevalence of severe proliferative diabetic retinopathy was higher in Group 2 (1.69% [severe] and 0.45% [proliferative]) than in Group 1 (1.01% and 0.11%, respectively). Diabetic macular edema was more prevalent in Group 2 (2.03%). Conclusions: The inclusion of general practitioners in the screening method seems to be important. A great number of patients with diabetes mellitus were screened, and a higher percentage of patients with diabetic retinopathy or macular edema were detected.
Hypertensive Retinopathy in Normotensive Blacks: About 3 Cases  [PDF]
Benedicte Carine Boka, Iklo Coulibaly, Hermann Yao, Ghyslain Ouffouet, Marie-Paule Bernadette Ncho-Mottoh, Arnaud Kouadio Ekou
World Journal of Cardiovascular Diseases (WJCD) , 2018, DOI: 10.4236/wjcd.2018.87037
Abstract: In case of hypertension, hypertensive retinopathy is normally an indicator of target organ damage. This sign can be frequently detected even in normotensive subjects. Among 94 normotensive volunteers chosen with regard of the hypertensive status of their parents, we could report the case of 3 black women who had hypertensive retinopathy. As changes in retinal microvasculature precede other signs of damage, we suggest fundus photography routine to be performed more frequently in assessing cardiovascular risks in hypertensive individual and their offspring, especially in black African population, where hypertension is severe.
PREVALENCE OF DIABETIC RETINOPATHY IN A PRIMARY CARE SETTING USING DIGITAL RETINAL IMAGING TECHNOLOGY
Keah Say Hien,Chng Kooi Seng
Malaysian Family Physician , 2006,
Abstract: The objective of this study was to determine the prevalence of diabetic retinopathy in a primary care setting using digital retinal imaging technology and to quantify the degree of diabetic retinopathy using internationally accepted severity scales. Two hundred patients with type 2 diabetes were evaluated clinically followed by fundus photography. The prevalence of retinopathy and maculopathy was 47.4% and 59.2% respectively (both retinopathy and maculopathy 34.7%). The high prevalence of retinal abnormality in this study is a cause for concern as most patients had diabetes for only 5 years or less.
Dyslipidemia and lipid peroxidation of Saudi type 2 diabetics with proliferative retinopathy
Yousef H. Aldebasi,Abdelmarouf H. Mohieldien,Yousef S. Almansour,Barakat L. Almutairi
Saudi Medical Journal , 2013,
Abstract: Objectives: To assess lipid profile and lipid peroxidation in type 2 diabetics with proliferative retinopathy (PDR), and investigate the association between these biochemical parameters and PDR. Methods: This study was conducted between June 2011 and February 2012 in the Research Laboratory, College of Applied Medical Sciences, Qassim University, Qasssim, Kingdom of Saudi Arabia. The study included 54 patients with type 2 diabetes (21 with PDR and 33 controls) and 30 healthy subjects. The biochemical parameters were measured using standard laboratory procedures. Results: Patients with PDR characterized by significantly (p<0.05) increased levels of serum cholesterol, triglyceride, low density lipoprotein (LDL-C), plasma malondialdehyde; decreased levels of serum high density lipoprotein (HDL-C) and apolipoprotein A1 (Apo A1); positive correlation of malondialdehyde with triglyceride, but negative with HDL-C, Apo A1. In logistic regression, malondialdehyde, LDL-C, and Apo A1 were not associated with PDR. However, triglyceride (OR = 1.745; p=0.000), total cholesterol (OR = 0.079; p=0.000), and HDL-C (OR = 10.676; p=0.000) were independent risk factors for developing PDR. Conclusion: Dyslipidemia and lipid peroxidation may play a role in pathogenesis of diabetic retinopathy. Patients with PDR displayed marked lipid abnormalities and increased lipid peroxidation. The control of lipid alterations through glycemic control and/or lipid lowering medication is required for type 2 diabetics at least to postpone or prevent loss of vision from retinopathy.
Prevalence of Diabetic Retinopathy among Diabetics: A Hospital Based Study at Ashraff Memorial Hospital, Kalmunai
Mohammed Muzammil Al-Ameen Rizath, Jayasiri Deshapriya Dias, Hameem Mohammed Ismy Mohammed, Mohamed Meerasahib Maroozathul Ilahi, Athambawa Mohamed Razmy
Open Access Library Journal (OALib Journal) , 2015, DOI: 10.4236/oalib.1102230
Abstract: Diabetic Retinopathy and diabetics are two highly associated severe diseases in human. This study assesses the risk of getting Diabetic Retinopathy among the Diabetic patients in the Kalmunai region. In this hospital based cross sectional study, all the diabetic patients who were attending to the diabetic clinic of the Ashraff memorial hospital from January 2014 to December 2014 were screened for Diabetic Retinopathy and their demographic details were recorded. Obtained information was analyzed for estimating the risk for Diabetic Retinopathy among the diabetic patients and it was estimated as 13.16%. No difference in risk of getting Diabetic Retinopathy was observed among different age group, educated level and gender. Risk of getting Diabetic Retinopathy increases with the increase of the duration suffered by the diabetic. The relative risk of getting Diabetic Retinopathy for patients with diabetic for more 12 years is 3.55 times greater compared to the fresh diabetic patients.
Effective and accurate screening for diabetic retinopathy using a 60o mydriatic fundus camera
TR Carmichael, GI Carp, ND Welsh, WJ Kalk
South African Medical Journal , 2005,
Abstract: Objectives. To establish whether an experienced endocrinologist could screen accurately for diabetic retinopathy using mydriatic 60° fundus photographs compared with a reference standard, viz. the combined highest scores of two experienced ophthalmologists. Design. Retrospective review of 60° colour transparency photographs taken over a 6-year period. Retinopathy was graded in a standardised way. Setting. Patients attending the diabetic clinic at Johannesburg Hospital, South Africa. Subjects. Fifteen hundred and seventeen patients (2 446 eyes) formed the basis for the study. Patients were included if there was more than 50% readability of the fundus photographs. Outcome measures. Outcome measures were prevalence of any retinopathy and presence of referable (severe) retinopathy. Interobserver agreement was measured using the kappa statistic, and sensitivity and specificity of the screener were evaluated. Results. The prevalence of retinopathy at the clinic was approximately 30%, but only about 12% was severe enough to warrant referral to the ophthalmology outpatient department. The endocrinologist was very accurate in determining cases requiring referral; there was 97% agreement with the reference standard, viz. the combined highest score of two experienced ophthalmologists (gold standard). Correlation on the determination of any retinopathy was less accurate (80% agreement), mostly owing to the endocrinologist reporting more isolated microaneurysms than the ophthalmologists. The screening method used gave a sensitivity of 83% and specificity of 99% which are within recommended standards. Conclusions. The screening strategy using a mydriatic fundus camera at the diabetic clinic was found to be effective and accurate and greatly reduced the number of possible referrals to the ophthalmology outpatient department. S Afr Med J 2005; 95: 57-61.
Recognising and managing diabetic retinopathy
Anthony Hall
Community Eye Health Journal , 2011,
Abstract: The management of diabetic retinopathy (DR) depends on accurately recognising or classifying the different types of DR and knowing what treatment to give the patient.DR has clinical signs which can be seen with an ophthalmoscope or with a slit lamp and a 90- or 78-dioptre lens. The advantage of the slit lamp is that it allows you to visualise the retina with both eyes. This stereoscopic vision provides a sense of depth which aids diagnosis, particularly of macular oedema. Other aids to DR diagnosis are fundus photography, fluorescein angiography, and optical coherence tomography.
The Communal System for Early Detection Microaneurysm and Diabetic Retinopathy Grading Through Color Fundus Images
N. Venkata Krishna,N. Venkata Siva Reddy,M. Venkata Ramana,E. Prasanna Kumar
International Journal of Scientific Engineering and Technology , 2013,
Abstract: Reliable microaneurysm detection in digital fundus images is still an open issue in medical image processing. We propose an ensemble-based framework to improve microaneurysm detection. Unlike the well-known approach of considering the output of multiple classifiers, we propose a combination of internal components of microaneurysm detectors, namely preprocessing methods and candidate extractors. Sincemicroaneurysm detection is decisivein diabetic retinopathy grading, we also tested the proposed method for this task on the publicly available Messidor database.
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