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1.
Acta Vet Hung ; 72(2): 80-98, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38916958

RESUMO

The aim of the study was to characterize retinal atrophy (RA) with progressive retinal atrophy symptoms in mixed breed dogs using ophthalmoscopy, spectral domain optical coherence tomography (SD-OCT) and electroretinography (ERG).The study was performed on 13 mixed breed dogs affected by retinal atrophy (11 males and 2 females that were 1.5-14 years old). Depending on the advancement of RA, SD-OCT examinations identified retinal abnormalities ranging from layer disorganisation to advanced atrophy. The most advanced RA occurred ventral to the optic disc. Total retinal thickness in both eyes (mean ± SD) was lower in dogs with RA compared to controls dorsally (77.7 ± 39.5 µm vs 173.5 ± 13.3 µm), ventrally (33.4 ± 29.9 µm vs 139.5 ± 10.8 µm), nasally (65.0 ± 34.5 µm vs 163.9 ± 11.0 µm) and temporally (61.8 ± 41.7 µm vs 171.9 ± 11.1 µm) to the optic disc. In dogs with locally normal architecture of inner retina, loss of definition of outer retinal layers occurred in many regions. Dark and light-adapted ERGs were reduced in 2 dogs with RA and were unrecordable in 11 dogs. Lesions evident in SD-OCT scans of mixed breed dogs affected with retinal atrophy initially appear ventrally to the optic disc and ventro-dorsally in advanced RA. In all mixed breed dogs with retinal atrophy, clinical signs and SD-OCT results correlate with ERG findings.


Assuntos
Doenças do Cão , Eletrorretinografia , Tomografia de Coerência Óptica , Animais , Cães , Tomografia de Coerência Óptica/veterinária , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/patologia , Feminino , Eletrorretinografia/veterinária , Masculino , Retina/diagnóstico por imagem , Retina/patologia , Doenças Retinianas/veterinária , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/patologia , Atrofia/veterinária
2.
Comput Methods Programs Biomed ; 254: 108253, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861878

RESUMO

BACKGROUND AND OBJECTIVES: Optical coherence tomography (OCT) has ushered in a transformative era in the domain of ophthalmology, offering non-invasive imaging with high resolution for ocular disease detection. OCT, which is frequently used in diagnosing fundamental ocular pathologies, such as glaucoma and age-related macular degeneration (AMD), plays an important role in the widespread adoption of this technology. Apart from glaucoma and AMD, we will also investigate pertinent pathologies, such as epiretinal membrane (ERM), macular hole (MH), macular dystrophy (MD), vitreomacular traction (VMT), diabetic maculopathy (DMP), cystoid macular edema (CME), central serous chorioretinopathy (CSC), diabetic macular edema (DME), diabetic retinopathy (DR), drusen, glaucomatous optic neuropathy (GON), neovascular AMD (nAMD), myopia macular degeneration (MMD) and choroidal neovascularization (CNV) diseases. This comprehensive review examines the role that OCT-derived images play in detecting, characterizing, and monitoring eye diseases. METHOD: The 2020 PRISMA guideline was used to structure a systematic review of research on various eye conditions using machine learning (ML) or deep learning (DL) techniques. A thorough search across IEEE, PubMed, Web of Science, and Scopus databases yielded 1787 publications, of which 1136 remained after removing duplicates. Subsequent exclusion of conference papers, review papers, and non-open-access articles reduced the selection to 511 articles. Further scrutiny led to the exclusion of 435 more articles due to lower-quality indexing or irrelevance, resulting in 76 journal articles for the review. RESULTS: During our investigation, we found that a major challenge for ML-based decision support is the abundance of features and the determination of their significance. In contrast, DL-based decision support is characterized by a plug-and-play nature rather than relying on a trial-and-error approach. Furthermore, we observed that pre-trained networks are practical and especially useful when working on complex images such as OCT. Consequently, pre-trained deep networks were frequently utilized for classification tasks. Currently, medical decision support aims to reduce the workload of ophthalmologists and retina specialists during routine tasks. In the future, it might be possible to create continuous learning systems that can predict ocular pathologies by identifying subtle changes in OCT images.


Assuntos
Inteligência Artificial , Retina , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Retina/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Aprendizado de Máquina , Aprendizado Profundo
3.
J Neurol ; 271(5): 2285-2297, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38430271

RESUMO

BACKGROUND: Stroke is a leading cause of morbidity and mortality. Retinal imaging allows non-invasive assessment of the microvasculature. Consequently, retinal imaging is a technology which is garnering increasing attention as a means of assessing cardiovascular health and stroke risk. METHODS: A biomedical literature search was performed to identify prospective studies that assess the role of retinal imaging derived biomarkers as indicators of stroke risk. RESULTS: Twenty-four studies were included in this systematic review. The available evidence suggests that wider retinal venules, lower fractal dimension, increased arteriolar tortuosity, presence of retinopathy, and presence of retinal emboli are associated with increased likelihood of stroke. There is weaker evidence to suggest that narrower arterioles and the presence of individual retinopathy traits such as microaneurysms and arteriovenous nicking indicate increased stroke risk. Our review identified three models utilizing artificial intelligence algorithms for the analysis of retinal images to predict stroke. Two of these focused on fundus photographs, whilst one also utilized optical coherence tomography (OCT) technology images. The constructed models performed similarly to conventional risk scores but did not significantly exceed their performance. Only two studies identified in this review used OCT imaging, despite the higher dimensionality of this data. CONCLUSION: Whilst there is strong evidence that retinal imaging features can be used to indicate stroke risk, there is currently no predictive model which significantly outperforms conventional risk scores. To develop clinically useful tools, future research should focus on utilization of deep learning algorithms, validation in external cohorts, and analysis of OCT images.


Assuntos
Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Medição de Risco , Retina/diagnóstico por imagem , Retina/patologia
4.
Niger J Clin Pract ; 26(7): 1011-1016, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37635588

RESUMO

Background: Optical coherence tomography (OCT) is widely used as the standard of care in evaluating macular and retinovascular diseases. However, the degree of OCT utilization is yet to be researched in a resource-limited country where wide gaps exist in access to healthcare. Aim: To determine the rate of utilization of the OCT in diagnosis, pre-treatment, and post-treatment evaluation of macular and retinovascular diseases treated with intravitreal anti-vascular endothelial growth factor injection (IVI). Patients and Methods: Retrospective, consecutive, and non-comparative case series of eyes diagnosed and treated from Jan 2017 to Jan 2022 for seven macular and retinovascular diseases in five eye clinics in Nigeria. Data extracted include demographics, indication for IVI, eye treated, use or non-use of OCT at the diagnosis (pre-treatment) and after the last IVI (post-treatment), and central macular thickness (CMT) of pre-treatment OCT scans. Results: Seven hundred and forty two eyes were diagnosed with retinovascular and macular diseases (389 right eyes and 353 left eyes).The male to female ratio was 430: 312 eyes. The mean age was, 63.89 years (SD 12.58). Four hundred and fifty two eyes (60.9%) had a pre-treatment OCT, 235 eyes (31.7%) had a post-treatment OCT, and 190 eyes (25.6%) had both pre- and post-treatment OCTs. The rate of pre-treatment OCT varied with the diagnosis (P = 0.000); DME had the highest rate, 74.4%, and HRVO had the lowest, 40%. Post-treatment OCT rate varied with the diagnosis (P = 0.009); non-AMD CNVM had the highest rate, 49.1%, and PCV had the lowest, 24.6%. Pre-treatment OCT rate was influenced by clinic location (P = 0.000); higher in clinics having an OCT. Post-treatment OCT was not influenced by clinic location (P = 0.37). A CRVO eye had the highest maximum CMT (1031 microns) of all the pre treatment eyes and the lowest minimum CMT of all the pre treatment eyes was in a BRVO eye (138 microns). Mean CMT was highest in HRVO (475.33 microns) and lowest in CNVM (307.62 microns). Conclusion: Though OCT is the standard of care for managing retinovascular and macular diseases, this research quantifies the extent of its use in Nigeria and finds it to be low. A post-treatment OCT rate of 32% suggests that urgent steps are required to improve access to OCT for IVI patients.


Assuntos
Doenças Retinianas , Tomografia de Coerência Óptica , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/terapia , Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Gerenciamento Clínico , Países em Desenvolvimento , Nigéria
5.
J Fr Ophtalmol ; 45(10): 1198-1208, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36266145

RESUMO

En face optical coherence tomography (EF-OCT) is a rapid, non-invasive, high-resolution imaging technique that has evolved in recent years to be a routine examination for the assessment and follow-up of various vitreoretinal diseases. With the introduction of swept-source OCT (SS-OCT), which can achieve up to 100,000 A-scans per second and better-quality imaging of deeper structures using a longer wavelength (1050nm), EF-OCT reconstruction can produce high-resolution frontal images of the retina and choroid (C-Scans) that give an overview of disease extent. These images allow a more accurate study of vitreoretinal interface pathologies such as epiretinal membranes, macular holes, and vitreomacular traction. They also provide key information in the study of various retinal vascular diseases and the differential diagnosis of cystic macular edema. EF-OCT provides valuable information about the severity of vitreoretinal interface alterations and precisely assesses the choriocapillaris and choroidal vasculature in pachychoroid disorders. Finally, this technique provides valuable information about atrophic and neovascular age-related macular degeneration and various uveitic entities. This review aims to describe the current clinical applications of EF-OCT in various vitreoretinal diseases as well as the latest findings and future perspectives.


Assuntos
Membrana Epirretiniana , Doenças Retinianas , Humanos , Tomografia de Coerência Óptica/métodos , Corioide/patologia , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/patologia , Retina/patologia , Membrana Epirretiniana/patologia
6.
Sci Rep ; 12(1): 10455, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729197

RESUMO

Image quality assessment is essential for retinopathy detection on color fundus retinal image. However, most studies focused on the classification of good and poor quality without considering the different types of poor quality. This study developed an automatic retinal image analysis (ARIA) method, incorporating transfer net ResNet50 deep network with the automatic features generation approach to automatically assess image quality, and distinguish eye-abnormality-associated-poor-quality from artefact-associated-poor-quality on color fundus retinal images. A total of 2434 retinal images, including 1439 good quality and 995 poor quality (483 eye-abnormality-associated-poor-quality and 512 artefact-associated-poor-quality), were used for training, testing, and 10-ford cross-validation. We also analyzed the external validation with the clinical diagnosis of eye abnormality as the reference standard to evaluate the performance of the method. The sensitivity, specificity, and accuracy for testing good quality against poor quality were 98.0%, 99.1%, and 98.6%, and for differentiating between eye-abnormality-associated-poor-quality and artefact-associated-poor-quality were 92.2%, 93.8%, and 93.0%, respectively. In external validation, our method achieved an area under the ROC curve of 0.997 for the overall quality classification and 0.915 for the classification of two types of poor quality. The proposed approach, ARIA, showed good performance in testing, 10-fold cross validation and external validation. This study provides a novel angle for image quality screening based on the different poor quality types and corresponding dealing methods. It suggested that the ARIA can be used as a screening tool in the preliminary stage of retinopathy grading by telemedicine or artificial intelligence analysis.


Assuntos
Retinopatia Diabética , Doenças Retinianas , Algoritmos , Inteligência Artificial , Retinopatia Diabética/diagnóstico por imagem , Fundo de Olho , Humanos , Processamento de Imagem Assistida por Computador/métodos , Doenças Retinianas/diagnóstico por imagem
7.
BMC Ophthalmol ; 22(1): 139, 2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35346124

RESUMO

PURPOSE: To develop a deep learning-based framework to improve the image quality of optical coherence tomography (OCT) and evaluate its image enhancement effect with the traditional image averaging method from a clinical perspective. METHODS: 359 normal eyes and 456 eyes with various retinal conditions were included. A deep learning framework with high-resolution representation was developed to achieve image quality enhancement for OCT images. The quantitative comparisons, including expert subjective scores from ophthalmologists and three objective metrics of image quality (structural similarity index measure (SSIM), peak signal-to-noise ratio (PSNR) and contrast-to-noise ratio (CNR)), were performed between deep learning method and traditional image averaging. RESULTS: With the increase of frame count from 1 to 20, our deep learning method always obtained higher SSIM and PSNR values than the image averaging method while importing the same number of frames. When we selected 5 frames as inputs, the local objective assessment with CNR illustrated that the deep learning method had more obvious tissue contrast enhancement than averaging method. The subjective scores of image quality were all highest in our deep learning method, both for normal retinal structure and various retinal lesions. All the objective and subjective indicators had significant statistical differences (P < 0.05). CONCLUSION: Compared to traditional image averaging methods, our proposed deep learning enhancement framework can achieve a reasonable trade-off between image quality and scanning times, reducing the number of repeated scans.


Assuntos
Aprendizado Profundo , Doenças Retinianas , Humanos , Aumento da Imagem/métodos , Doenças Retinianas/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos
9.
Retina ; 41(8): 1754-1761, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315816

RESUMO

PURPOSE: To report trends of intravitreal corticosteroid use and explore the relationship between career experience, reported industry payments, and prescribing habits. METHODS: A retrospective review of ophthalmologists who administered intravitreal dexamethasone implants (DEX) and triamcinolone acetonide (TA) injections between August 2013 and December 2017. RESULTS: A total of 1,070 US ophthalmologists were reimbursed by Medicare for 522,804 DEX injections and 2.6 million TA injections. There was a significant positive trend in the number of DEX (P = 0.01), but not TA, injections per year. Mid-career and late-career physicians performed significantly greater total injections on average compared with early-career physicians (both P < 0.001). Early-career physicians performed a greater proportion of DEX injections than late-career physicians (P = 0.006). Industry payments were positively associated with the proportion of DEX used and inversely correlated with the proportion of TA administered (P < 0.001). On multivariate analysis, years in practice, number of payments, and total value of payments were significantly associated with the number of DEX injections administered (all P < 0.001). CONCLUSION: From 2013 to 2017, the use of DEX increased, whereas TA use remained stable. There was a positive association between DEX use and physician-industry interactions, which may be explained by seniority and experience. This study does not define a causal relationship.


Assuntos
Dexametasona/administração & dosagem , Medicare , Oftalmologistas/estatística & dados numéricos , Doenças Retinianas/diagnóstico por imagem , Triancinolona Acetonida/administração & dosagem , Adulto , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/economia , Estudos Retrospectivos , Estados Unidos , Adulto Jovem
10.
Expert Rev Med Devices ; 17(10): 1095-1108, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32885710

RESUMO

INTRODUCTION: Retinal imaging is a key investigation in ophthalmology. New devices continue to be created to keep up with the demand for better imaging modalities in this field. This review looks to highlight current trends and the future of retinal imaging. AREAS COVERED: This review looks at the advances in topographical imaging, photoacoustic microscopy, optical coherence tomography and molecular imaging. There is future scoping on further advances in retinal imaging. EXPERT OPINION: Retinal imaging continues to develop at a rapid pace to improve diagnosis and management of patients. We will see the development of big data to gain powerful insights and new technologies such as teleophthalmology mature in the future.


Assuntos
Imageamento Tridimensional/tendências , Doenças Retinianas/diagnóstico por imagem , Angiografia , Fundo de Olho , Humanos , Oftalmoscopia , Tomografia de Coerência Óptica
11.
Med Arch ; 74(3): 191-194, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32801434

RESUMO

INTRODUCTION: Optical coherence tomography angiography (OCT-A) is a useful diagnostic tool for assessing eyes' health in patients with chronic diseases, such as diabetes, hypertension, Parkinson's disease and chronic kidney disease (CKD). AIM: To detect changes in macular structure and retinal vascular meshwork in the macular area and peripapillary in patients with chronic kidney disease (CKD). METHODS: This cross-sectional study included 80 eyes of patients with CKD in stages 2, 3 or 4, who were followed-up in the Nephrology Clinic of University Clinical Center Sarajevo. All patients were categorized according to the stage of CKD. All patients were scanned by a high-speed 840-nm-wavelength spectral-domain optical coherence tomography instrument (RTVue XR Avanti; Optovue, Inc, Fremont, California, USA). Blood flow was detected using a split-spectrum amplitude-decorrelation angiography algorithm. A fully automated microstructural analysis of the foveal avascular zone (FAZ), FAZ perimeter, foveal vessel density in a 300-µm area around the FAZ (FD), nonflow area, flow index in superficial and deep vascular plexus, choriocapillary flow, vascular density, radial peripapillary capillary density was performed. RESULTS: When comparing patients with CKD stage 2 and stage 3 there were no statistically significant changes in microvascular parameters on OCT angiography, as well as when comparing patients with CKD stage 3 and stage 4. But in the comparison between patients with less developed CKD (stage 2) and terminal CKD (stage 4) there was a significant difference between some microvascular parameters such as FAZ area, FAZ perimeter, choriocapillary flow. CONCLUSION: Many studies demonstrated that evaluation of the microvascular changes in different retinal layers using SS-OCTA may be considered as a key to assessing the systemic perfusion status. Evaluation of retinal microvasculature may ease the management and approach of patients with CKD, having in mind that the retinal and the kidney vascular network are, concerning structure, development and the function, very similar.


Assuntos
Insuficiência Renal Crônica/fisiopatologia , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Angiografia , Estudos Transversais , Feminino , Fóvea Central/irrigação sanguínea , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Microcirculação , Microvasos/diagnóstico por imagem , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Insuficiência Renal Crônica/complicações , Doenças Retinianas/complicações , Vasos Retinianos/fisiopatologia , Tomografia de Coerência Óptica
12.
Graefes Arch Clin Exp Ophthalmol ; 258(6): 1261-1268, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32162113

RESUMO

PURPOSE: The aim of this study is to evaluate the retinal microvascular density in SLE patients using optical coherence tomography angiography (OCTA) and to correlate vascular density with the disease activity and damage risk. METHODS: Twenty eyes of 20 SLE patients were compared with 20 eyes of normal subjects. The retinal capillary plexuses were examined by OCTA. The disease activity and damage risk were evaluated by the SLEDAI-2 K and SLICC/ACR SDI scoring systems. RESULTS: No difference was found between SLE patients' central foveal thickness (CFT) and foveal avascular zone (FAZ) area and the normal (P > 0.05). SLE patients had slightly lower superficial vessel densities than normal in the upper and lower macular regions (P < 0.05), sparing the middle sectors (P > 0.05). In the deep plexus, vessel density loss was detected in all sectors (P < 0.001). The vessel density in 300-µm-wide region around the FAZ (FD-300) and the acircularity index (AI) were affected in the SLE in comparison to the normal group (P < 0.05). No significant correlation was found between the SLEDAI-2 k and the retinal vessel density in either layer, while the SLICC/SDI had moderate inverse correlation with vessel density in some sectors (P < 0.05). Receiver operating characteristic (ROC) curve analysis showed that the deep capillary plexus had high sensitivity and specificity for detecting vascular damage in SLE patients. CONCLUSIONS: OCTA permits noninvasive quantitative assessment of retinal vessel density in SLE, allowing early detection of altered retinal circulation. Vessel density could be included in future assessment of SLE activity and damage scores.


Assuntos
Lúpus Eritematoso Sistêmico/fisiopatologia , Doenças Retinianas/patologia , Vasos Retinianos/patologia , Adulto , Área Sob a Curva , Capilares/diagnóstico por imagem , Capilares/patologia , Estudos Transversais , Feminino , Angiofluoresceinografia , Fóvea Central/irrigação sanguínea , Humanos , Pressão Intraocular/fisiologia , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Masculino , Microvasos/diagnóstico por imagem , Microvasos/patologia , Curva ROC , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Adulto Jovem
13.
Med Image Anal ; 61: 101654, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32066065

RESUMO

Objective and quantitative assessment of fundus image quality is essential for the diagnosis of retinal diseases. The major factors in fundus image quality assessment are image artifact, clarity, and field definition. Unfortunately, most of existing quality assessment methods focus on the quality of overall image, without interpretable quality feedback for real-time adjustment. Furthermore, these models are often sensitive to the specific imaging devices, and cannot generalize well under different imaging conditions. This paper presents a new multi-task domain adaptation framework to automatically assess fundus image quality. The proposed framework provides interpretable quality assessment with both quantitative scores and quality visualization for potential real-time image recapture with proper adjustment. In particular, the present approach can detect optic disc and fovea structures as landmarks, to assist the assessment through coarse-to-fine feature encoding. The framework also exploit semi-tied adversarial discriminative domain adaptation to make the model generalizable across different data sources. Experimental results demonstrated that the proposed algorithm outperforms different state-of-the-art approaches and achieves an area under the ROC curve of 0.9455 for the overall quality classification.


Assuntos
Fundo de Olho , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Disco Óptico/diagnóstico por imagem , Fotografação , Doenças Retinianas/diagnóstico por imagem , Artefatos , Conjuntos de Dados como Assunto , Humanos
14.
Eur J Ophthalmol ; 30(2): 235-244, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31242750

RESUMO

Diseases of the optic nerve head involving changes in blood flow are common. However, the pathophysiology is not always fully understood. Several non-invasive methods for measuring optic nerve head blood flow are available, but currently no gold standard has been established. Methods for measuring blood flow in optic neuropathies including colour Doppler imaging, retinal function imager, optical coherence tomography angiography and laser speckle flowgraphy are reviewed. Ultrasound colour Doppler imaging is a fast measurement technique where several different parameters, especially the blood flow velocity, can be calculated. Though used for many years in ophthalmology, its use is not standardized and it requires significant observer skills. The retinal function imager is a direct method where the haemoglobin in erythrocytes is visualized and blood flow velocities in retinal vessels are calculated from a series of photos. The technique is not suitable for direct measurement of blood flow within the optic nerve head. Laser speckle flowgraphy uses a laser light which creates a light scatter pattern in the tissue. Particles moving in the area causes changes in the speckle pattern from which a relative blood flow can be estimated. It is, however, not known whether optic nerve head microcirculation is measurable with the technique. Optical coherence tomography angiography uses multiple scans to evaluate blood flow with good reproducibility but often problems with artefacts. The technique is continuously being refined and increasingly used in research as a tool for the study of blood flow in retinopathies and optic neuropathies. Most of the conducted studies are based on small sample sizes, but some of the methods show promising results in an optic nerve head blood flow research setting. Further and larger studies are required to provide standardized and comparable measurements before one or more of the methods can be considered clinical helpful in daily practice.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Fluxometria por Laser-Doppler , Disco Óptico/irrigação sanguínea , Doenças Retinianas/diagnóstico por imagem , Tomografia de Coerência Óptica , Velocidade do Fluxo Sanguíneo/fisiologia , Humanos , Fluxometria por Laser-Doppler/métodos , Fluxo Sanguíneo Regional/fisiologia , Reprodutibilidade dos Testes , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos
15.
Invest Ophthalmol Vis Sci ; 60(7): 2667-2675, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31242288

RESUMO

Purpose: Fabry disease (FD) is a multiorgan X-linked condition characterized by a deficiency of the lysosomal enzyme alpha-galactosidase A, resulting in a progressive intralysosomal deposit of globotriaosylceramide. The aim of this study was to evaluate the macular ultrastructure of the vascular network using optical coherence tomography angiography (OCTA) and to evaluate macular function using focal electroretinography (fERG) in Fabry patients (FPs). Methods: A total of 20 FPs (38 eyes, mean age 57 ± 2.12 SD, range of 27-80 years) and 17 healthy controls (27 eyes, mean age 45 years ± 20.50 SD, range of 24-65 years) were enrolled in the study. Color fundus photography, swept-source optical coherence tomography (SS-OCT), OCTA and fERG were performed in all subjects. The OCTA foveal avascular zone (FAZ), vasculature structure, superficial and deep retinal plexus densities (images of 4.5 × 4.5 mm) and fERG amplitudes were measured. Group differences were statistically assessed by Student's t-test and ANOVA. Results: In the FP group, the FAZ areas of the superficial and deep plexuses were enlarged (P = 0.036, t = 2.138; P < 0.001, t = -3.889, respectively), the vessel density was increased in the superficial plexus, and the fERG amplitude was reduced (P < 0.001, t = -10.647) compared with those in healthy controls. No significant correlations were found between the structural and functional data. Conclusions: OCTA vascular abnormalities and reduced fERG amplitudes indicate subclinical signs of microangiopathy with early retinal dysfunction in FPs. This study highlights the relevance of OCTA imaging analysis in the identification of abnormal macular vasculature as an ocular hallmark of FD.


Assuntos
Doença de Fabry/fisiopatologia , Macula Lutea/irrigação sanguínea , Doenças Retinianas/fisiopatologia , Vasos Retinianos/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrorretinografia , Doença de Fabry/diagnóstico por imagem , Feminino , Angiofluoresceinografia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual
16.
BMJ Case Rep ; 12(2)2019 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-30718265

RESUMO

Welding light can cause photic retinal injury. We report binocular maculopathy induced by a brief exposure to electric arc welding light in a patient who could not equipped with protective device because of narrow space. A 47-year-old man performed electric arc welding for approximately 10-15 min without wearing protective device because of narrow space and subsequently experienced eye discomfort and decreased visual acuity. At the initial visit, his best corrected visual acuity was 0.5. Fundus examination, optical coherence tomography (OCT) and multifocal electroretinogram (mfERG) were performed. OCT showed disruption in the ellipsoid zone, and mfERG amplitudes in the central 10° were markedly reduced in both eyes. The decrease in visual acuity had been noted for at least 18 months. Using the proper protective device is essential in welding, despite short time periods of work. For patients with welding-induced photokeratitis, doctors should also consider the possibility of photic retinal injury.


Assuntos
Traumatismos Oculares/diagnóstico por imagem , Macula Lutea/lesões , Traumatismos Ocupacionais/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Soldagem , Eletrorretinografia , Traumatismos Oculares/fisiopatologia , Dispositivos de Proteção dos Olhos , Fundo de Olho , Humanos , Macula Lutea/diagnóstico por imagem , Macula Lutea/fisiopatologia , Masculino , Pessoa de Meia-Idade , Traumatismos Ocupacionais/fisiopatologia , Retina/diagnóstico por imagem , Retina/lesões , Retina/fisiopatologia , Doenças Retinianas/fisiopatologia , Tomografia de Coerência Óptica , Indenização aos Trabalhadores
17.
Retina ; 39(12): 2384-2391, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334922

RESUMO

PURPOSE: This study aims at describing the macular vascular features of the eyes of pediatric patients with the homozygous form of sickle cell disease (SCD) using optical coherence tomography angiography. METHODS: This is a retrospective case series of eyes of pediatric patients with SCD, race- and age-matched to those of healthy individuals. Using optical coherence tomography angiography images of superficial capillary plexus and deep capillary plexus, the nonflow area, vascular density, and foveal avascular zone were measured. The remodeled microvascular foveal architectures obtained on optical coherence tomography angiography and fluorescein angiography were compared. RESULTS: A total of 19 eyes of patients with SCD and 18 eyes of race-matched healthy controls were examined. The best-corrected visual acuity ranged from 75 to 85 letters in all cases. In the SCD series, 8 eyes displayed signs of retinopathy on funduscopy. The foveal avascular zone was significantly enlarged, the foveal vascular density was 8% lower, and there were more perifoveal vascular alterations in the eyes of patients with SCD compared to those of controls. CONCLUSION: The foveal vascular density was significantly reduced and area of the foveal avascular zone was significantly increased in the eyes of patients with SCD. Consistent architectural changes in the perifoveal capillaries were also observed in the pediatric patients with SCD.


Assuntos
Anemia Falciforme/fisiopatologia , Doenças Retinianas/fisiopatologia , Vasos Retinianos/patologia , Anemia Falciforme/diagnóstico por imagem , Criança , Feminino , Angiofluoresceinografia , Voluntários Saudáveis , Humanos , Masculino , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-30440251

RESUMO

Optical coherence tomography (OCT) is an essential medical imaging tool for retinal disease diagnosis. Nevertheless, as with all optical imaging techniques, image degradation is a very common phenomenon, affecting the quality of the images. In this paper, we address issues related to the resolution of OCT images and propose solutions based on solving inverse problems. A cost function for deconvolution and super-resolution is formulated and the alternating direction method of multiplier (ADMM) and forward-backward splitting (FBS) algorithms are then employed for its minimisation. On the one hand, the standard Ll norm regularisation with soft thresholding is compared with a total variation (TV) regularisation within an ADMM scheme. On the other hand, nonconvex regularisation is also considered via a multivariate generalisation of the minimax-concave scheme in FBS. In the latter case, the regularisation function is judiciously chosen in order to preserve the overall convexity of the cost function. To be able to evaluate our algorithms qualitatively, a number of standard images are initially used. Then, we also assess our algorithms subjectively by applying them to real OCT images of the human eye. Given that the point spread function (PSF) of OCT images is generally unknown, we also propose ways of estimating it in the deconvolution component of our methods. Our results show that the ADMM scheme with soft thresholding achieves the best performance in terms of enhancing the overall quality of OCT images.


Assuntos
Tomografia de Coerência Óptica/métodos , Algoritmos , Humanos , Doenças Retinianas/diagnóstico por imagem , Tomografia de Coerência Óptica/economia
19.
Sci Rep ; 8(1): 5103, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29572456

RESUMO

This retrospective consecutive case series aimed to evaluate spectral-domain optical coherence tomography (SD-OCT) for occult macular disease recognition preoperatively in patients scheduled for routine cataract surgery. All patients scheduled for cataract surgery underwent macular SD-OCT. Scans were reviewed for retinal, retinal pigment epithelium and vitreomacular interface abnormalities. For the subgroup analysis, the following information was collected: age; sex; and diabetes, hypertension, myopia, glaucoma, post intra-ocular surgery, endophotocoagulation, retinal vasculopathy and uveitis statuses. One-thousand-one-hundred-seventy-six consecutive scans were acquired from 1,176 patients. Macular pathology was found in 294 eyes. The most common macular disorders were an epiretinal membrane (n = 130), myopia atrophy (n = 61) and a dome-shaped macular with pathologic myopia (n = 32). One-hundred-thirty eyes (11.05%) presented macular epiretinal membranes not detected by dilated fundus examination, accounting for 44.22% of the abnormalities in diseased eyes and was higher than in previous Chinese studies. Some had multiple macular disorders. The most common ocular history was myopia, including high myopia. The pooled prevalence rate of macular diseases detected by OCT was 0.24 (95% CI 0.14-0.34) using meta-analysis. SD-OCT should be performed for routine cataract surgery patients to evaluate visual outcomes, especially in myopic patients and those considering advanced-technology intraocular lenses.


Assuntos
Extração de Catarata , Macula Lutea/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Catarata/epidemiologia , Extração de Catarata/métodos , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/epidemiologia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos
20.
BMJ Open ; 7(12): e017923, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29275341

RESUMO

BACKGROUND/AIMS: To develop a standardised grading scheme, using standard photos, for spectral-domain ocular coherence tomography (SD-OCT) images of the posterior eye and evaluate the interobserver agreement among trained ophthalmologists in identifying pathological changes. METHODS: Subjects were recruited from Liwan District, Guangzhou, with SD-OCT data collection from June 2013 to November 2013 as part of 10-year follow-up visits from the Liwan Eye Study. All subjects underwent SD-OCT imaging of the macula with scanning lines analysed by two ophthalmologists to assess for the presence of 12 different posterior segment lesions. Per cent agreement for each lesion between the graders and quantitative measures of dome-shaped macula (DSM) height and choroidal thickness were calculated. RESULTS: A total of 679 SD-OCT images from 679 subjects were independently evaluated by the two graders. Each of the 12 lesions was successfully graded as present or absent in over 96% of images. For all lesions, per cent agreement between observers was over 90%, ranging from 90.7% for epiretinal membranes and retinal pigment epithelium thickenings to 99.7% for full thickness macular holes and retinal detachments. Quantitative measurements of DSM height and choroidal thickness at three locations of the eye all exhibited intraclass correlation scores between the two graders of greater than 0.9. CONCLUSION: Our study demonstrates high concordance between graders in characterising posterior segment lesions using SD-OCT images, validating the continued use of this imaging modality in the diagnosis of posterior eye disease.


Assuntos
Doenças Retinianas/diagnóstico por imagem , Epitélio Pigmentado da Retina/patologia , Tomografia de Coerência Óptica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epitélio Pigmentado da Retina/diagnóstico por imagem , Acuidade Visual
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