Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 16.464
Filtrar
1.
Zhonghua Yan Ke Za Zhi ; 56(12): 914-919, 2020 Dec 11.
Artigo em Chinês | MEDLINE | ID: mdl-33342117

RESUMO

Objective: To summarize the clinical and fundus imaging features of purified protein derivative and T-spot positive tubercular serpiginous-like choroiditis (PTP-SLC) patients. Methods: This retrospective study consecutively enrolled 13 PTP-SLC patients (21 eyes) in Beijing Tongren Hospital from November 2015 to November 2017. There were 8 males and 5 females with an average age of (45.2±12.1) years. Medical history and results of systemic and ophthalmological examinations, such us fundus autofluorescence photography, optical coherence tomography (OCT), fluorescein fundus angiography (FFA) and indocyanine green angiography, were evaluated. Results: Eight patients had binocular disease with an average interval time of (8.4±7.9) years. The average visual acuity of all patients was 0.3, and 4 patients had a clear history of exposure to tuberculosis. The active lesions in the PTP-SLC patients were homogeneous and creamish-yellow with unclear boundaries. Fundus autofluorescence showed an ill-defined, diffuse hyperautofluorescent zone. OCT showed punctate hyperreflexes between the choroidal stroma, destruction of the outer retinal structure with intraretinal edema and discrete vitreal hyper-reflective spots. FFA showed hypofluorescence in the active lesion at early stage and diffuse hyperfluorescence with leakage. Indocyanine green angiography showed persistent hypofluorescence. Conclusions: PTP-SLC fundus lesions are mainly manifested as homogeneous creamish-yellow lesions with unclear boundaries and high in autofluorescence. The involvement of the choroid and the outer layer of the retina can be observed on OCT. FFA can find more retinal vascular inflammatory changes. It is difficult to distinguish PTP-SLC from serpiginous choroiditis simply based on clinical and epidemiological characteristics. The pathogenic examination of tuberculosis is still the key to differential diagnosis (Chin J Ophthalmol, 2020, 56: 914-919).


Assuntos
Corioidite , Síndromes do Ponto Branco , Adulto , Corioidite/diagnóstico por imagem , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica
2.
Zhonghua Yan Ke Za Zhi ; 56(12): 920-927, 2020 Dec 11.
Artigo em Chinês | MEDLINE | ID: mdl-33342118

RESUMO

Objective: To develop a fundus image quality assessment system based on computer vision technology and to verify its accuracy by comparing the results of artificial discrimination and using this system. Methods: The process of image evaluation was divided into four modules: fundus image preprocessing, fundus image quality evaluation, fundus image content detection and evaluation result output. The system was designed to automatically evaluate the image quality of each fundus image, identify the optic disc and macula, and judge whether the image was qualified or not according to the image quality discrimination rules. A total of 2 397 fundus images of 787 type 2 diabetes patients were selected as the test data set. The average age of the patients, including 384 males and 403 females, was (69.65±19.09) years old. The images were taken by the staff of community health service centers in Shanghai with a fundus camera. The fundus image quality assessment system was used to conduct quality control and classification of the data set. At the same time, 12 professional fundus picture readers were employed to conduct manual quality control and classification of this data set. The system quality control results and artificial quality discrimination results were compared and analyzed. Results: The fundus image quality assessment system automatically recognized left and right eyes and eye positions on the input fundus images. The quality control interface included four indicator lights, which respectively corresponded to the images with the optic disc or macula as the center of the left or right eye. Evaluation of each fundus image was completed within 1 second, and the results were automatically displayed on the user interface. The 2 397 fundus photos were identified manually as 1 846 qualified photos and 551 unqualified photos. Among the unqualified images, 62 (11.27%) were too dark, 51 (9.27%) were too bright, 59 (10.73%) were not clear in the macular area, 36 (6.54%) showed no macula or optic disc, 125 (22.73%) could not present the fundus structure, 175 (31.82%) were blurred, and 42 (7.64%) were blocked. The results of the system and manual assessment were consistent in 1 788 qualified images (96.86%) and 550 unqualified images (99.82%), with an overall consistency rate of 97.54%. Conclusion: The fundus image quality assessment system can achieve highly consistent results with the professional judgment of ophthalmologists and has the characteristics of objectivity. (Chin J Ophthalmol, 2020, 56:920-927).


Assuntos
Diabetes Mellitus Tipo 2 , Idoso , Idoso de 80 Anos ou mais , China , Computadores , Feminino , Fundo de Olho , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Tecnologia
3.
Zhonghua Yan Ke Za Zhi ; 56(12): 950-955, 2020 Dec 11.
Artigo em Chinês | MEDLINE | ID: mdl-33342122

RESUMO

Optical coherence tomography angiography (OCTA) is a novel, non-invasive imaging technology, which could acquire volumetric angiographic information. Numerous studies have reported the potential clinical use of OCTA in a variety of common retinal disorders. Polypoidal choroidal vasculopathy (PCV) is characterized by the formation of branching choroidal vascular networks (BVN) with terminal dilatations (polyps). Indocyanine green angiography (ICGA) remains the golden diagnostic standard for PCV. The clinical application of OCTA in PCV is also widely investigated recent years. But the results are controversially interpreted. In addition to various diagnostic accuracy of PCV from different studies, the clinical application of OCTA in PCV is limited. With the constant innovation of fundus imaging techniques, OCTA is reaching greater investigation depth and become more accurate at picking up blood flow signals, which also improves the diagnostic accuracy of PCV. In this paper, we reviewed the clinical application and research progress of OCTA in PCV, in order to provide some assistant for clinical practice and correct interpretation of the reports. (Chin J Ophthalmol, 2020, 56:950-955).


Assuntos
Doenças da Coroide , Neovascularização de Coroide , Corioide/diagnóstico por imagem , Doenças da Coroide/diagnóstico por imagem , Neovascularização de Coroide/diagnóstico por imagem , Angiofluoresceinografia , Fundo de Olho , Humanos , Verde de Indocianina , Estudos Retrospectivos , Tomografia de Coerência Óptica
4.
Rom J Ophthalmol ; 64(3): 285-291, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33367162

RESUMO

Purpose: To describe the central three-dimensional (3D) thickness profile of the macula (CMT) and the subfoveal choroidal region (SFCT) in diabetic retinopathy (DR) following panretinal laser photocoagulation (PRP) using swept-source optical coherence tomography (SS-OCT). Methods: A prospective observational study including 17 eyes with proliferative DR (PDR) and 27 eyes with severe nonproliferative DR (sNPDR)] for whom PRP was done. All subjects received SS-OCT imaging before and 3 months after PRP (POM#3). SFCT and CMT changes were analysed at both visits. Intraclass Correlation Coefficients (ICC) and Coefficients of Variation (COV) were used to test the accuracy of thickness data. Results: SFCT has thinned from 233 ± 54 µm before PRP treatment to 216 ± 51 µm 3 months later (p < 0.001). Likewise, CMT declined at POM#3 as compared to pre-PRP status (p<0.001). SFCT was thinner in PDR before and at POM#3 (p<0.05) than sNPDR; whereas, no significant difference was observed in CMT between both groups in the two visits. No significant changes were found between groups in SFCT and CMT at POM#3. Regarding reliability, ICCSFCT=0.98 and ICCCMT=0.99. The COVs for CMT and SFCT were 5.03% and 5.91%, respectively. Conclusion: The mean SFCT and CMT decreased 3 months after PRP. We also reported reliability of SFCT measurements in DR using SS-OCT. Abbreviations: SS = Swept-Source, TD = time domain, SD = spectral domain, FD = Fourier-domain, 3D = three-dimensional, 2D = two-dimensional.


Assuntos
Corioide/patologia , Retinopatia Diabética/diagnóstico , Fotocoagulação a Laser/métodos , Retina/patologia , Tomografia de Coerência Óptica/métodos , Retinopatia Diabética/cirurgia , Feminino , Angiofluoresceinografia/métodos , Seguimentos , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Retina/cirurgia , Estudos Retrospectivos
5.
Ocul Immunol Inflamm ; 28(8): 1285-1289, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33021422

RESUMO

PURPOSE: To describe a case of inflammatory chorioretinopathy and Adie's syndrome possibly associated with COVID-19. METHODS: Observational case report. RESULTS: A 51-year-old woman developed fever, cough, and headache followed by retro-ocular pain and reading impairment. She tested positive for SARS-COV-2 infection by qualitative real-time reverse-transcriptase-polymerase-chain-reaction. The slit-lamp and funduscopic exam revealed abnormal pupillary response and yellowish creamy deep chorioretinal lesions, which were not present in previous examinations. Instillation of pilocarpine demonstrated denervation supersensitivity, and it was suggestive of bilateral Adie tonic pupil. A comprehensive work-up ruled out other systemic, autoimmune, or infectious diseases. CONCLUSIONS: This case illustrates the possible association between multifocal chorioretinitis and Adie's syndrome, and the SARS-COV-2 infection in humans. Further investigation of virus infectivity specifically within ocular tissues has to be conducted.


Assuntos
Síndrome de Adie/etiologia , Betacoronavirus , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Acuidade Visual , Síndrome de Adie/diagnóstico , Infecções por Coronavirus/epidemiologia , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Tomografia de Coerência Óptica
6.
Ocul Immunol Inflamm ; 28(8): 1298-1300, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33021846

RESUMO

PURPOSE: To report a unique case of intraocular inflammation and outer retinal changes in a patient with coronavirus disease (COVID-19). CASE REPORT: A 57-year-old woman was seen 12 days after COVID-19 symptoms onset confirmed by positive IgM and IgG serological tests. No anterior chamber cells were seen. Color fundus photograph showed a yellowish lesion within the macular area, and fluorescein angiography revealed hyperfluorescence on the topography of the macular lesion in both eyes. Spectral-domain optical coherence tomography demonstrated hyperreflective pinpoints at the level of posterior vitreous hyaloid, corresponding to vitritis, hyperreflective lesions at the level of inner plexiform and ganglion cell layers, and disruption of the ellipsoid zone. CONCLUSION AND IMPORTANCE: COVID-19 is known to affect the inner retinal layers. The current case not only supports but also adds a vitreal and an outer retinal layer involvement that might also be caused by this infectious disease.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Oftalmopatias/etiologia , Angiofluoresceinografia/métodos , Pneumonia Viral/complicações , Segmento Externo das Células Fotorreceptoras da Retina/patologia , Tomografia de Coerência Óptica/métodos , Corpo Vítreo/patologia , Infecções por Coronavirus/epidemiologia , Oftalmopatias/diagnóstico , Feminino , Fundo de Olho , Humanos , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Acuidade Visual
7.
Ocul Immunol Inflamm ; 28(8): 1293-1297, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33021856

RESUMO

A 53-year-old man presented with acute loss of vision, negative scotoma and dyschromatopsia in his left eye. He reported contact with people with severe respiratory syndrome - coronavirus-2 (SARS-CoV-2) 8 days prior symptoms. Funduscopic examination revealed several retinal hemorrhages. Spectral-domain optical coherence tomography showed lesions consistent with acute macular neuroretinopathy and paracentral acute middle maculopathy. Quickly after his presentation, SARSCov-2 was confirmed by chest computed tomography-scan and RT-PCR in this patient. Thrombotic complications associated with Covid-19 infection have high incidence and may involve the retina. We described a case of retinal involvement associated with Covid-19 infection. PRÉCIS: Funduscopic examination revealed retinal hemorrhages in a man with loss of vision. Optical coherence tomography showed an acute macular neuroretinopathy and paracentral acute middle maculopathy. Coronavirus disease was confirmed by chest computed tomography-scan and RT-PCR.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Angiofluoresceinografia/métodos , Macula Lutea/patologia , Pneumonia Viral/complicações , Doenças Retinianas/etiologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Doença Aguda , Infecções por Coronavirus/epidemiologia , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Pandemias , Pneumonia Viral/epidemiologia , Doenças Retinianas/diagnóstico
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1540-1543, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018285

RESUMO

This paper proposes a new method for automatic detection of glaucoma from stereo pair of fundus images. The basis for detecting glaucoma is using the optic cup-to-disc area ratio, where the surface area of the optic cup is segmented from the disparity map estimated from the stereo fundus image pair. More specifically, we first estimate the disparity map from the stereo image pair. Then, the optic disc is segmented from one of the stereo image. Based upon the location of the optic disc, we perform an active contour segmentation on the disparity map to segment the optic cup. Thereafter, we can compute the optic cup-to-disc area ratio by dividing the area (i.e. the total number of pixels) of the segmented optic cup region to that of the segmented optic disc region. Our experimental results using the available test dataset shows the efficacy of our proposed approach.


Assuntos
Glaucoma , Disco Óptico , Algoritmos , Fundo de Olho , Glaucoma/diagnóstico por imagem , Humanos , Disco Óptico/diagnóstico por imagem
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1560-1563, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018290

RESUMO

The characteristics of diabetic retinopathy (DR) fundus images generally consist of multiple types of lesions which provided strong evidence for the ophthalmologists to make diagnosis. It is particularly significant to figure out an efficient method to not only accurately classify DR fundus images but also recognize all kinds of lesions on them. In this paper, a deep learning-based multi-label classification model with Gradient-weighted Class Activation Mapping (Grad-CAM) was proposed, which can both make DR classification and automatically locate the regions of different lesions. To reducing laborious annotation work and improve the efficiency of labeling, this paper innovatively considered different types of lesions as different labels for a fundus image so that this paper changed the task of lesion detection into that of image classification. A total of five labels were pre-defined and 3228 fundus images were collected for developing our model. The architecture of deep learning model was designed by ourselves based on ResNet. Through experiments on the test images, this method acquired a sensitive of 93.9% and a specificity of 94.4% on DR classification. Moreover, the corresponding regions of lesions were reasonably outlined on the DR fundus images.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/diagnóstico por imagem , Fundo de Olho , Humanos , Sensibilidade e Especificidade
10.
Vestn Oftalmol ; 136(5): 136-141, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33056975

RESUMO

At present, age-related macular degeneration (AMD) takes third place among the causes of blindness and low vision in the middle-aged and senile persons. The medical and social significance of this pathology is motivated by the possibility of losing central vision and general ability to perform professional duties. One of the modern methods of diagnostics of this disease is eye fundus autofluorescence. Its introduction into everyday clinical practice increases the effectiveness of detecting early signs of AMD and helps clarify the indications for the appointment of conservative treatment.


Assuntos
Degeneração Macular , Baixa Visão , Cegueira , Fundo de Olho , Humanos , Degeneração Macular/diagnóstico , Pessoa de Meia-Idade
11.
Klin Monbl Augenheilkd ; 237(10): 1225-1229, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-33059379

RESUMO

One of the most controversial discussions in retinal surgery is currently being held about the importance of intraoperative OCT (iOCT). The background is the desire to combine the 2-dimensional fundus view of the surgeon with the layered depth information of OCT to achieve a 4-dimensional "augmented reality" (3-D plus change over time). This should help to visualise fine structures, which have been hidden from the surgeon's view. Therefore, retinal surgery seems to be predestined for the use of iOCT. The great hope is that a dynamic live 3-D image with real-time feedback will provide the surgeon with additional information and improve safety. Although fascinating at the first glance, in the surgical routine, however, iOCT technology is disappointing, especially in macular surgery. It rarely provides substantial information that would not be obtainable without iOCT or that would not be available in much better quality through preoperative diagnostic testing. Only some special indications remain, particularly related to subretinal surgery.


Assuntos
Retina , Tomografia de Coerência Óptica , Fundo de Olho , Procedimentos Cirúrgicos Oftalmológicos , Retina/diagnóstico por imagem , Retina/cirurgia , Corpo Vítreo
12.
PLoS One ; 15(10): e0240109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33007029

RESUMO

PURPOSE: To compare the properties of the lamina cribrosa (LC) and the peripapillary vessel density between branch retinal vein occlusion (BRVO) and normal-tension glaucoma (NTG), using swept-source optical coherence tomography and optical coherence tomography angiography. METHODS: This retrospective study included 21 eyes of 21 patients with BRVO and 43 eyes of 43 patients with NTG who were treated from June 2016 to September 2017. The anterior LC depth (ALCD) and LC thickness (LCT) at the mid-superior, central, and mid-inferior levels; the mean difference in ALCD; and the peripapillary vessel density in the superficial and deep capillary plexuses and the choriocapillaris were compared between groups. RESULTS: ALCD at the mid-superior, central, and mid-inferior levels was significantly greater in the NTG group (P < 0.05), while LCT was comparable between the groups. The mean difference in ALCD was significantly greater in the BRVO group (P = 0.03). The peripapillary vessel density in the superotemporal segment of the superficial capillary plexus was significantly lower in the BRVO group, while the density in all segments of the choriocapillaris was significantly lower in the NTG group (P < 0.05 for all). CONCLUSIONS: Our findings demonstrate that BRVO and NTG have different LC structures and peripapillary vessel densities.


Assuntos
Glaucoma de Baixa Tensão/patologia , Oclusão da Veia Retiniana/patologia , Vasos Retinianos/patologia , Idoso , Feminino , Fundo de Olho , Humanos , Glaucoma de Baixa Tensão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/patologia , Reprodutibilidade dos Testes , Oclusão da Veia Retiniana/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1360-1363, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018241

RESUMO

Registration of multimodal retinal images is of great importance in facilitating the diagnosis and treatment of many eye diseases, such as the registration between color fundus images and optical coherence tomography (OCT) images. However, it is difficult to obtain ground truth, and most existing algorithms are for rigid registration without considering the optical distortion. In this paper, we present an unsupervised learning method for deformable registration between the two images. To solve the registration problem, the structure achieves a multi-level receptive field and takes contour and local detail into account. To measure the edge difference caused by different distortions in the optics center and edge, an edge similarity (ES) loss term is proposed, so loss function is composed by local cross-correlation, edge similarity and diffusion regularizer on the spatial gradients of the deformation matrix. Thus, we propose a multi-scale input layer, U-net with dilated convolution structure, squeeze excitation (SE) block and spatial transformer layers. Quantitative experiments prove the proposed framework is best compared with several conventional and deep learningbased methods, and our ES loss and structure combined with Unet and multi-scale layers achieve competitive results for normal and abnormal images.


Assuntos
Algoritmos , Retina , Fundo de Olho , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1404-1407, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018252

RESUMO

Diabetic retinopathy (DR) is a progressive eye disease that affects a large portion of working-age adults. DR, which may progress to an irreversible state that causes blindness, can be diagnosed with a comprehensive dilated eye exam. With the eye dilated, the Doctor takes pictures of the inside of the eye via a medical procedure called Fluorescein Angiography, in which a dye is injected into the bloodstream. The dye highlights the blood vessels in the back of the eye so they can be photographed. In addition, the Doctor may request an Optical Coherence Tomography (OCT) exam, by which cross-sectional photos of the retina are produced to measure the thickness of the retina. Early prognostication is vital in treating the disease and preventing it from progressing into advanced irreversible stages. Skilled medical personnel and necessary medical facilities are required to detect DR in its five major stages. In this paper, we propose a diagnostic tool to detect Diabetic retinopathy from fundus images by using an ensemble of multi-inception CNN networks. Our inception block consists of three Convolutional layers with kernel sizes of 3x3, 5x5, and 1x1 that are concatenated deeply and forwarded to the max-pooling layer. We experimentally compare our proposed method with two pre-trained models: VGG16 and GoogleNets. The experiment results show that the proposed method can achieve an accuracy of 93.2% by an ensemble of 10 random networks, compared to 81% obtained with transfer learning based on VGG19.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Estudos Transversais , Retinopatia Diabética/diagnóstico , Fundo de Olho , Humanos , Redes Neurais de Computação , Tomografia de Coerência Óptica
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1592-1595, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018298

RESUMO

Clinically, the Fundus Fluorescein Angiography (FA) is a more common mean for Diabetic Retinopathy (DR) detection since the DR appears in FA much more contrasty than in Color Fundus Image (CF). However, acquiring FA has a risk of death due to the fluorescent allergy. Thus, in this paper, we explore a novel unpaired CycleGAN-based model for the FA synthesis from CF, where some strict structure similarity constraints are employed to guarantee the perfectly mapping from one domain to another one. First, a triple multi-scale network architecture with multi-scale inputs, multi-scale discriminators and multi-scale cycle consistency losses is proposed to enhance the similarity between two retinal modalities from different scales. Second, the self-attention mechanism is introduced to improve the adaptive domain mapping ability of the model. Third, to further improve strict constraints in the feather level, quality loss is employed between each process of generation and reconstruction. Qualitative examples, as well as quantitative evaluation, are provided to support the robustness and the accuracy of our proposed method.


Assuntos
Retinopatia Diabética , Retina , Atenção , Retinopatia Diabética/diagnóstico , Angiofluoresceinografia , Fundo de Olho , Humanos , Retina/diagnóstico por imagem
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1976-1979, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018390

RESUMO

In this paper, we proposed and validated a probability distribution guided network for segmenting optic disc (OD) and optic cup (OC) from fundus images. Uncertainty is inevitable in deep learning, as induced by different sensors, insufficient samples, and inaccurate labeling. Since the input data and the corresponding ground truth label may be inaccurate, they may actually follow some potential distribution. In this study, a variational autoencoder (VAE) based network was proposed to estimate the joint distribution of the input image and the corresponding segmentation (both the ground truth segmentation and the predicted segmentation), making the segmentation network learn not only pixel-wise information but also semantic probability distribution. Moreover, we designed a building block, namely the Dilated Inception Block (DIB), for a better generalization of the model and a more effective extraction of multi-scale features. The proposed method was compared to several existing state-of-the-art methods. Superior segmentation performance has been observed over two datasets (ORIGA and REFUGE), with the mean Dice overlap coefficients being 96.57% and 95.81% for OD and 88.46% and 88.91% for OC.


Assuntos
Glaucoma , Disco Óptico , Animais , Fundo de Olho , Fundo Gástrico , Disco Óptico/diagnóstico por imagem , Probabilidade
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1984-1987, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018392

RESUMO

Fundus image is commonly used in aiding the diagnosis of ophthalmic diseases. A high-resolution (HR) image is valuable to provide the anatomic information on the eye conditions. Recently, image super-resolution (SR) though learning model has been shown to be an economic yet effective way to satisfy the high demands in the clinical practice. However, the reported methods ignore the mutual dependencies of low-and high-resolution images and did not fully exploit the dependencies between channels. To tackle with the drawbacks, we propose a novel network for fundus image SR, named by Fundus Cascaded Channel-wise Attention Network (FC-CAN). The proposed FCCAN cascades channel attention module and dense module jointly to exploit the semantic interdependencies both frequency and domain information across channels. The channel attention module rescales channel maps in spatial domain, while the dense module preserves the HR components by up- and down-sampling operation. Experimental results demonstrate the superiority of our net-work in comparison with the six methods.


Assuntos
Processamento de Imagem Assistida por Computador , Útero , Atenção , Feminino , Fundo de Olho , Fundo Gástrico
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1988-1991, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018393

RESUMO

In this work, we demonstrate a novel approach to assessing the risk of Diabetic Peripheral Neuropathy (DPN) using only the retinal images of the patients. Our methodology consists of convolutional neural network feature extraction, dimensionality reduction and feature selection with random projections, combination of image features to case-level representations, and the training and testing of a support vector machine classifier. Using clinical diagnosis as ground truth for DPN, we achieve an overall accuracy of 89% on a held-out test set, with sensitivity reaching 78% and specificity reaching 95%.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Neuropatias Diabéticas/diagnóstico , Fundo de Olho , Humanos , Aprendizado de Máquina , Fotografação , Medição de Risco
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1996-2002, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018395

RESUMO

This work proposes an automated algorithms for classifying retinal fundus images as cytomegalovirus retinitis (CMVR), normal, and other diseases. Adaptive wavelet packet transform (AWPT) was used to extract features. The retinal fundus images were transformed using a 4-level Haar wavelet packet (WP) transform. The first two best trees were obtained using Shannon and log energy entropy, while the third best tree was obtained using the Daubechies-4 mother wavelet with Shannon entropy. The coefficients of each node were extracted, where the feature value of each leaf node of the best tree was the average of the WP coefficients in that node, while those of other non-leaf nodes were set to zero. The feature vector was classified using an artificial neural network (ANN). The effectiveness of the algorithm was evaluated using ten-fold cross-validation over a dataset consisting of 1,011 images (310 CMVR, 240 normal, and 461 other diseases). In testing, a dataset consisting of 101 images (31 CMVR, 24 normal, and 46 other diseases), the AWPT-based ANN had sensitivities of 90.32%, 83.33%, and 91.30% and specificities of 95.71%, 94.81%, and 92.73%. In conclusion, the proposed algorithm has promising potential in CMVR screening, for which the AWPT-based ANN is applicable with scarce data and limited resources.


Assuntos
Retinite por Citomegalovirus , Algoritmos , Retinite por Citomegalovirus/diagnóstico , Fundo de Olho , Humanos , Redes Neurais de Computação , Análise de Ondaletas
20.
Ocul Immunol Inflamm ; 28(8): 1290-1292, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32976055

RESUMO

PURPOSE: To report a case of impending central retinal vein occlusion (iCRVO) in a COVID-19 patient. CASE REPORT: A 54 years old woman with COVID-19 related pneumonia presented to our emergency department complaining of scotomas and decreased vision in her right eye. Funduscopic examination and multimodal imaging revealed rare retinal hemorrhages, retinal whitening, and fern-like hypo-autofluorescent appearance typical of iCRVO. She had no risk factors other than a transient hyper-coagulability status likely related to the ongoing infection. Systemic treatment with steroids normalized her inflammatory and coagulation status and the occlusion completely resolved. CONCLUSIONS: Retinal circulation should be considered as a potential site for thromboembolic complications from COVID-19.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Angiofluoresceinografia/métodos , Pneumonia Viral/complicações , Retina/patologia , Oclusão da Veia Retiniana/etiologia , Tomografia de Coerência Óptica/métodos , Infecções por Coronavirus/epidemiologia , Feminino , Fundo de Olho , Humanos , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Oclusão da Veia Retiniana/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA