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1.
Ultrasonics ; 110: 106263, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33065466

RESUMEN

PURPOSE: To quantitatively investigate both optic nerve head (ONH) and peripapillary sclera (PPS) biomechanical properties of porcine eyes through an ultrasonic elastography imaging system in response to both increasing and decreasing intraocular pressure (IOP). METHODS: The Young's modulus of the ONH and PPS were assessed using our high resolution ultrasonic imaging system which utilized a mechanical shaker to induce shear waves and an off-axis aligned 40 MHz needle transducer to track micron-level displacement along the direction of wave propagation. In this study, imaging on a total of 8 ex vivo porcine eyes preloaded with IOPs from 6 mmHg to 30 mmHg was performed. To have a better understanding of the effect of varying IOP on biomechanics, both increasing and decreasing IOPs were investigated. RESULTS: The increase of the Young's modulus of ONH (92.4 ± 13.9 kPa at 6 mmHg to 224.7 ± 71.1 kPa at 30 mmHg) and PPS (176.8 ± 14.3 kPa at 6 mmHg to 573.5 ± 64.4 kPa at 30 mmHg) following IOP elevation could be observed in the reconstructed Young's modulus of the shear wave elasticity (SWE) imaging while the B-mode structural images remained almost unchanged. In addition, for the same IOP level, both ONH and PPS have a tendency to be stiffer with decreasing IOP as compared to increasing IOP. CONCLUSIONS: Our results demonstrate the feasibility of using our ultrasonic elastography system to investigate the stiffness mapping of posterior eye with high resolution in both increasing and decreasing IOPs, making this technique potentially useful for glaucoma.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Disco Óptico/fisiología , Esclerótica/fisiología , Animales , Fenómenos Biomecánicos , Módulo de Elasticidad , Diseño de Equipo , Glaucoma/diagnóstico por imagen , Técnicas In Vitro , Fantasmas de Imagen , Porcinos
2.
PLoS One ; 15(10): e0239913, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33002080

RESUMEN

Optic-disc photography (ODP) has proven to be very useful for optic nerve evaluation in glaucoma. In real clinical practice, however, limited patient cooperation, small pupils, or media opacities can limit the performance of ODP. The purpose of this study was to propose a deep-learning approach for increased resolution and improved legibility of ODP by contrast, color, and brightness compensation. Each high-resolution original ODP was transformed into two counterparts: (1) down-scaled 'low-resolution ODPs', and (2) 'compensated high-resolution ODPs' produced via enhancement of the visibility of the optic disc margin and surrounding retinal vessels using a customized image post-processing algorithm. Then, the differences between these two counterparts were directly learned through a super-resolution generative adversarial network (SR-GAN). Finally, by inputting the high-resolution ODPs into SR-GAN, 4-times-up-scaled and overall-color-and-brightness-transformed 'enhanced ODPs' could be obtained. General ophthalmologists were instructed (1) to assess each ODP's image quality, and (2) to note any abnormal findings, at 1-month intervals. The image quality score for the enhanced ODPs was significantly higher than that for the original ODP, and the overall optic disc hemorrhage (DH)-detection accuracy was significantly higher with the enhanced ODPs. We expect that this novel deep-learning approach will be applied to various types of ophthalmic images.


Asunto(s)
Aprendizaje Profundo , Glaucoma/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Disco Óptico/diagnóstico por imagen , Fotograbar/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/normas , Límite de Detección , Fotograbar/normas
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1540-1543, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018285

RESUMEN

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.


Asunto(s)
Glaucoma , Disco Óptico , Algoritmos , Fondo de Ojo , Glaucoma/diagnóstico por imagen , Humanos , Disco Óptico/diagnóstico por imagen
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1746-1749, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018335

RESUMEN

Glaucoma is a neurodegenerative disease of the visual system and is the leading cause of irreversible blindness worldwide. To date, its pathophysiological mechanisms remain unclear. This study evaluated the feasibility of advanced diffusion magnetic resonance imaging techniques for examining the microstructural environment of the visual pathway in glaucoma. While conventional diffusion tensor imaging (DTI) showed lower fractional anisotropy and higher directional diffusivities in the optic tracts of glaucoma patients than healthy controls, diffusion kurtosis imaging (DKI) and the extended white matter tract integrity (WMTI) model indicated lower radial kurtosis, higher axial and radial diffusivities in the extra-axonal space, lower axonal water fraction, and lower tortuosity in the same regions in glaucoma patients. These findings suggest glial involvements apart from compromised axonal integrity in glaucoma. In addition, DKI and WMTI but not DTI parameters significantly correlated with clinical ophthalmic measures via optical coherence tomography and visual field perimetry testing. Taken together, DKI and WMTI provided sensitive and comprehensive imaging biomarkers for quantifying glaucomatous damage in the white matter tract across clinical severity complementary to DTI.


Asunto(s)
Glaucoma , Enfermedades Neurodegenerativas , Tracto Óptico , Sustancia Blanca , Imagen de Difusión Tensora , Glaucoma/diagnóstico por imagen , Humanos , Sustancia Blanca/diagnóstico por imagen
5.
Brasília; CONITEC; out. 2020.
No convencional en Portugués | BRISA/RedTESA | ID: biblio-1141495

RESUMEN

INTRODUÇÃO: O glaucoma é uma doença progressiva, assintomática até seus estágios avançados e cujas lesões são irreversíveis. Estimam-se que cerca de 11,2 milhões de pessoas serão acometidas com cegueira bilateral em 2020, o que torna o glaucoma a principal causa de cegueira irreversível no mundo atualmente. O diagnóstico do glaucoma recomendado no PCDT de glaucoma é realizado por exames que se baseiam nos resultados da avaliação estrutural (disco ótico) e funcional (campo visual), associado ao acompanhamento dos níveis de PIO. O exame de Tomografia de Coerência Óptica ou "Optical Coherence Tomography" (OCT) é uma tecnologia computadorizada de imagem, importante ferramenta auxiliar na avaliação dos pacientes com glaucoma, capaz de otimizar a acurácia diagnóstica da doença, particularmente nas fases iniciais, propiciando melhor qualidade da assistência aos pacientes e menor ocorrência de diagnóstico incorreto ­ "overdiagnosis", com o consequente tratamento e frequência de seguimento desnecessário para indivíduos sem glaucoma, possibilitando alocação mais apropriada/racional dos recursos públicos em saúde. TECNOLOGIA: Tomografia de Coerência Óptica (OCT). PERGUNTA: O uso da Tomografia de Coerência Óptica melhora a acurácia do diagnóstico do glaucoma em pacientes suspeitos pelo aspecto do disco óptico, e/ou alterações do campo visual, e/ou PIO elevada? EVIDÊNCIAS CLÍNICAS: Foram incluídos 4 estudos, sendo 2 revisões sistemáticas (RS) e dois estudos transversais publicados após a elaboração das RS. Para o desfecho de área sob a curva ROC (AROCs), a RS mais recente apresentou resultados de AROCs entre 0.887 e 0.906 para o parâmetro da média da espessura da camada de fibras nervosas da retina (CFNR) e AROCs entre 0.835 e 0.901 para os parâmetros segmentares da mácula, além disso, não foram observadas diferenças estatisticamente significantes entre os aparelhos de OCT. Para o desfecho de desempenho diagnóstico de glaucoma, a acurácia da OCT foi medida de acordo com diferentes parâmetros e a acurácia foi maximizada pela avaliação da CFNR do setor inferior. A sensibilidade do teste foi de 72% (IC 95%: 65% - 77%) e a especificidade de 93% (IC 95%: 92% - 95%). A qualidade da evidência foi classificada como baixa, devido ao alto risco de viés agregado aos estudos primários e incertezas sobre os resultados. AVALIAÇÃO ECONÔMICA: O demandante apresentou uma análise de custo-efetividade para quantificar o impacto da incorporação da OCT no SUS, na confirmação diagnóstica dos casos suspeitos de glaucoma primário de ângulo aberto inicial. Estimou-se que o uso do exame de OCT levaria a uma redução de custo médio de R$ 428,78 por paciente por ano e um aumento absoluto de 76,4% no percentual de diagnósticos corretos. O modelo possui limitações que podem afetar os resultados, como os valores de entrada subestimados e não justificados ou descritos. ANÁLISE DE IMPACTO ORÇAMENTÁRIO: A análise de impacto orçamentário apresentada pelo demandante estimou uma economia para o SUS com a ampliação de uso de OCT, entre R$ 824 mil a R$ 4,5 milhões ao ano, com base nos tratamentos evitados de pacientes com diagnósticos incorretos. As premissas adotadas para o cálculo da população foram consideradas não adequadas ou inconsistentes e por isso os resultados podem estar subestimados, impossibilitando sua interpretação. IMPLEMENTAÇÃO: Apesar do demandante estimar uma economia de recursos totais na análise de impacto orçamentário, a realização do exame gera custos diretos de sua implementação. Levando em consideração o custo SIGTAP do procedimento e o número de pacientes ano a ano estimado pelo demandante, calculamos um custo de R$ 4,9 milhões para o primeiro ano até R$ 5,3 milhões no quinto ano de implementação. RECOMENDAÇÃO INICIAL DA CONITEC: A Conitec, em sua 89ª reunião ordinária, realizada no dia 06 de agosto de 2020, deliberou que a matéria fosse disponibilizada em consulta pública com recomendação preliminar favorável à ampliação de uso no SUS do exame de Tomografia de Coerência Óptica para confirmação diagnóstica do glaucoma em pacientes suspeitos pelo aspecto do disco óptico, e/ou alterações do campo visual, e/ou pressão intraocular elevada. CONSULTA PÚBLICA: Foram recebidas 272 contribuições, 34 pelo formulário Técnico-científico e 238 pelo formulário de Experiência e Opinião, sendo 265 (97%) concordantes com a recomendação preliminar. O tema mais citado nas contribuições diz respeito a acurácia diagnóstica do exame de OCT em detectar alterações glaucomatosas, outros temas foram "a independência da interpretação subjetiva do avaliador dos exames disponíveis", "acurácia em diagnosticar casos precoces de glaucoma" e relatos como "Exame imprescindível para avaliação completa do paciente". RECOMENDAÇÃO FINAL DA CONITEC: Os membros da Conitec presentes na 91ª reunião ordinária, no dia 08 de outubro de 2020, deliberaram por unanimidade recomendar a ampliação de uso do exame de tomografia de coerência óptica para confirmação diagnóstica de glaucoma, conforme Protocolo Clínico e Diretrizes Terapêuticas do Ministério da Saúde. Foi assinado o registro de deliberação nº 565/2020.


Asunto(s)
Humanos , Glaucoma/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Evaluación de la Tecnología Biomédica , Sistema Único de Salud , Brasil , Análisis Costo-Beneficio/economía
6.
PLoS One ; 15(6): e0234816, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32584833

RESUMEN

PURPOSE: To compare the retinal vessel density and glaucomatous parameters in primary angle closure glaucoma (PACG), to evaluate the diagnostic and monitoring abilities of the peripapillary and macular vessel density in the progression of glaucoma. METHODS: This was a observational, prospective and cross-sectional study. According to Glaucoma Staging System, 218 eyes (116 participants) were divided into 5 groups: no glaucoma, early glaucoma, moderate glaucoma, advance glaucoma, severe glaucoma. All participants underwent a comprehensive ocular examination, which included corrected distance visual acuity measurement, slit-lamp biomicroscopy, intra ocular pressure (IOP), gonioscopy, fundus examination, stereoscopic optic disc photography, Humphrey visual field test(VF), peripapillary and macular optical coherence tomography angiography(OCTA) scan. SPSS software was used to calculate and compare retinal vessel density (peripapillary vessel density, PVD and macular vessel density, MVD) and glaucomatous parameters (mean deviation (MD),pattern standard deviation(PSD), retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer(GCIPL),rim area, average cup/disc(C/D) ratio). RESULTS: The GCIPL thickness, RNFL thickness, PVD and MVD are significantly reduced in PACG. There were significant differences in all measurements among the groups (P<0.01).Reduced peripapillary and macular vessel density in glaucoma were detected and a statistically significant correlation with glaucoma stages (P<0.01). In addition, the results of retinal vessel density, reduced RNFL thickness and GCIPL thickness were also statistically related to the stage of glaucoma. As expected, the rim area was significantly smaller with higher C/D area ratios in glaucomatous eyes corresponding to the severity of disease. CONCLUSIONS: The changes of PVD and MVD had strongly positive correlation with GCIPL thickness and RNFL thickness, had negative correlation with the severity of glaucoma, which meant the more severe the glaucoma was, the lower PVD and MVD were. Compared to traditional glaucoma staging system judged by VF, the changes of PVD and MVD obtained by OCTA might be a new method to grade the stage of glaucoma. These findings theorize that the changes of PVD and MVD may be better facilitated for the observation and monitoring of glaucoma progression.


Asunto(s)
Angiografía , Glaucoma/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Tomografía de Coherencia Óptica , Anciano , Progresión de la Enfermedad , Femenino , Glaucoma/patología , Humanos , Masculino , Vasos Retinianos/patología
7.
Int J Comput Assist Radiol Surg ; 15(7): 1205-1213, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32445127

RESUMEN

PURPOSE: The cup-to-disc ratio (CDR), a clinical metric of the relative size of the optic cup to the optic disc, is a key indicator of glaucoma, a chronic eye disease leading to loss of vision. CDR can be measured from fundus images through the segmentation of optic disc and optic cup . Deep convolutional networks have been proposed to achieve biomedical image segmentation with less time and more accuracy, but requires large amounts of annotated training data on a target domain, which is often unavailable. Unsupervised domain adaptation framework alleviates this problem through leveraging off-the-shelf labeled data from its relevant source domains, which is realized by learning domain invariant features and improving the generalization capabilities of the segmentation model. METHODS: In this paper, we propose a WGAN domain adaptation framework for detecting optic disc-and-cup boundary in fundus images. Specifically, we build a novel adversarial domain adaptation framework that is guided by Wasserstein distance, therefore with better stability and convergence than typical adversarial methods. We finally evaluate our approach on publicly available datasets. RESULTS: Our experiments show that the proposed approach improves Intersection-over-Union score for optic disc-and-cup segmentation, Dice score and reduces the root-mean-square error of cup-to-disc ratio, when we compare it with direct transfer learning and other state-of-the-art adversarial domain adaptation methods. CONCLUSION: With this work, we demonstrate that WGAN guided domain adaptation obtains a state-of-the-art performance for the joint optic disc-and-cup segmentation in fundus images.


Asunto(s)
Aprendizaje Profundo , Fondo de Ojo , Glaucoma/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Disco Óptico/diagnóstico por imagen , Imagen Óptica/métodos , Humanos
8.
Invest Ophthalmol Vis Sci ; 61(5): 56, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32460317

RESUMEN

Purpose: To investigate the spatial characteristics and patterns of structural progression using the combined retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer event-based progression analysis feature provided by the Guided Progression Analysis (GPA) software of spectral-domain optical coherence tomography. Methods: In this retrospective observational study, we evaluated 89 patients with open-angle glaucoma showing clinically confirmed structural progression within a minimum follow-up period of 3 years. For each eye, the RNFL and ganglion cell-inner plexiform layer GPA data were extracted from serial spectral-domain optical coherence tomography (HD-OCT 4000, Carl Zeiss Meditec, Inc., Dublin, CA) data from 2012 to 2017 (available in commercial report). A combined wide-field GPA map was merged using vascular landmark-guided superimposition of RNFL and ganglion cell-inner plexiform layer GPA event-based progression maps onto the RNFL image (resulting in the GPA PanoMaps: proposed in this study). The pattern of progressive structural changes was evaluated by comparing the baseline combined wide-field OCT deviation maps (PanoMap deviation maps: available in commercial report) and GPA PanoMaps at the time the first progression was detected and the GPA PanoMaps at the last follow-up. Spatial characteristics and patterns of glaucoma structural progression on GPA PanoMaps were evaluated. Results: Progressive structural progression was detected most frequently at the macular vulnerability zone (MVZ), with the peripapillary and macular progression being well-correlated spatially. Compared with the baseline structural change on PanoMap, the progressive structural changes extended toward the fovea at both the peripapillary and macular areas. A spatial difference was observed between the areas where structural damage was frequently found on PanoMap (peripapillary inferoinferior sector and macular MVZ) and areas where progression was frequently found on GPA PanoMap (peripapillary and macular MVZ). Conclusions: The patterns of progressive glaucomatous structural changes in both the peripapillary and macular areas were confirmed on the combined wide-field GPA map (GPA PanoMap). An analysis of the progression pattern using the GPA PanoMap facilitates the understanding of the spatial relation between the peripapillary and macular areas in glaucoma.


Asunto(s)
Progresión de la Enfermedad , Glaucoma/diagnóstico por imagen , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
9.
Invest Ophthalmol Vis Sci ; 61(4): 41, 2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32343781

RESUMEN

Purpose: To measure the ex vivo pressure-induced strain response of the human optic nerve head and analyze for variations with glaucoma diagnosis and optic nerve axon damage. Methods: The posterior sclera of 16 eyes from 8 diagnosed glaucoma donors and 10 eyes from 6 donors with no history of glaucoma were inflation tested between 5 and 45 mm Hg. The optic nerve from each donor was examined for degree of axon loss. The posterior volume of the lamina cribrosa (LC) was imaged with second harmonic generation and analyzed using volume correlation to calculate LC strains between 5 and 10 and 5 and 45 mm Hg. Results: Eye length and LC area were larger in eyes diagnosed with glaucoma (P ≤ 0.03). Nasal-temporal EXX and circumferential Eθθ strains were lower in the LC of diagnosed glaucoma eyes at 10 mm Hg (P ≤ 0.05) and 45 mm Hg (P ≤ 0.07). EXX was smaller in the LC of glaucoma eyes with <25% axon loss compared with undamaged normal eyes (P = 0.01, 45 mm Hg). In general, the strains were larger in the peripheral than central LC. The ratio of the maximum principal strain Emax in the peripheral to central LC was larger in glaucoma eyes with >25% axon loss than in glaucoma eyes with milder damage (P = 0.004, 10 mm Hg). Conclusions: The stiffness of the LC pressure-strain response was greater in diagnosed glaucoma eyes and varied with glaucomatous axon damage. Lower LC strains in glaucoma eyes with milder damage may represent baseline biomechanical behavior that contributes to axon loss, whereas greater LC strain and altered radial LC strain variation in glaucoma eyes with more severe damage may be caused by glaucoma-related remodeling.


Asunto(s)
Glaucoma/diagnóstico por imagen , Glaucoma/fisiopatología , Imagenología Tridimensional , Disco Óptico/diagnóstico por imagen , Disco Óptico/patología , Estrés Mecánico , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Estudios de Casos y Controles , Femenino , Humanos , Técnicas In Vitro , Masculino , Valores de Referencia , Esclerótica/diagnóstico por imagen , Esclerótica/patología , Manejo de Especímenes
10.
Invest Ophthalmol Vis Sci ; 61(4): 43, 2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32343786

RESUMEN

Purpose: To evaluate episcleral vasculature in corneal limbus with optical coherence tomography angiography (OCTA) in normal controls, port-wine stain (PWS) patients, and Sturge-Weber syndrome (SWS) patients. Methods: Unilateral eyes from 18 normal controls (25.41 ± 4.00 years), 16 PWS patients (21.35 ± 11.05 years), and 8 SWS patients with ipsilateral late-onset glaucoma (22.13 ± 7.82 years). Each subject underwent slit-lamp examination, applanation tonometry, and OCTA. All OCTA scans were performed using an OCTA system operating at a wavelength of 1050-nm in four quadrants (superior, inferior, nasal, and temporal). The scans were delineated into conjunctival and episcleral layers using IMAGEnet6 for analysis. Results: Slit-lamp and OCTA images demonstrated dense dilated episcleral vessels in PWS and SWS patients, particularly in the SWS group. The mean limbal involvements of episcleral vascular anomalies under slit lamp were respectively 0.00 ± 0.00, 5.44 ± 2.92, and 8.88 ± 2.70 clock hours in the control, PWS, and SWS groups (F = 58.46, P < 0.01). Quantitative analysis of OCTA scans showed that the episcleral vessel density in controls, PWS, and SWS groups were 25.03% ± 1.47%, 28.28% ± 1.96%, and 33.59% ± 3.00%, respectively (F = 18.17, P < 0.01). We also observed higher episcleral vessel diameter index in the SWS and PWS groups in comparison with the controls, particularly in the SWS group (P < 0.01). The vessel measurements, including density and diameter, were significantly correlated with the increased IOP and cup-to-disc (C/D) in SWS patients (P < 0.01). Conclusions: To our knowledge, this is the first demonstration of OCTA in PWS and SWS patients and represents direct pathoanatomic evidence for episcleral alterations in SWS patients. The episcleral vessel measurements correlated with the increased IOP and C/D in SWS patients, indicating the episcleral vascular hypertrophy may be a risk factor for glaucoma in adult SWS patients.


Asunto(s)
Angiografía/métodos , Glaucoma/etiología , Mancha Vino de Oporto/diagnóstico por imagen , Síndrome de Sturge-Weber/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Adolescente , Adulto , Factores de Edad , Estudios de Casos y Controles , Niño , Femenino , Glaucoma/diagnóstico , Glaucoma/diagnóstico por imagen , Glaucoma/patología , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Proyectos Piloto , Mancha Vino de Oporto/complicaciones , Mancha Vino de Oporto/patología , Pronóstico , Valores de Referencia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Microscopía con Lámpara de Hendidura/métodos , Síndrome de Sturge-Weber/complicaciones , Síndrome de Sturge-Weber/patología , Tonometría Ocular/métodos
11.
Sci Rep ; 10(1): 6845, 2020 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-32322012

RESUMEN

Changes in retinal vasculature and ocular circulation may play an important role in the glaucoma development and progression. We evaluated the vertical asymmetry across the temporal raphe of the deep retinal layer vessel density, using swept-source optical coherence tomography angiography (SS-OCTA), and its relationship with the central visual field (VF) loss. Thirty-four eyes of 27 patients with open-angle glaucoma were included. SS-OCTA macular scanning was performed within a 3 × 3 mm (300 × 300 pixels) volume, centred on the fovea. The relationships between the vertical asymmetrical deep retinal vessel density reduction (ADRVD) across the temporal raphe and various ocular parameters were analysed. Twenty-two glaucomatous eyes with ADRVDs had central VF loss. Contrarily, ADRVDs were not found in any of the 12 eyes without central VF loss. Thirteen eyes (59.1%) with central VF loss had ADRVDs topographically corresponding to the central VF loss and macular ganglion cell complex thinning. The glaucomatous eyes with ADRVDs exhibited inferior rather than superior central VF loss (P = 0.032). Thus, ADRVD specifically indicates the glaucomatous central visual loss. Further analysis of ADRVD may improve our understanding on glaucoma pathogenesis, offering new treatment insights.


Asunto(s)
Glaucoma/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Tomografía de Coherencia Óptica , Anciano , Estudios Transversales , Femenino , Glaucoma/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Vasos Retinianos/fisiopatología
12.
Klin Monbl Augenheilkd ; 237(7): 879-888, 2020 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-32274775

RESUMEN

BACKGROUND: The foveal avascular zone (FAZ) - with perimeter and acircularity index (AI) and surrounding vessel density - are measured in glaucomatous eyes in comparison to healthy eyes - with additional subdivision into visual field defects in different locations (central vs. peripheral). MATERIALS AND METHODS: The data from 128 eyes were evaluated. Firstly, glaucomatous eyes (n = 74) were compared with healthy eyes (n = 54). In addition, glaucomatous eyes with a central visual field defect (ZGD, n = 19) and eyes with peripheral visual field defect (PGD, n = 34) were differentiated. The FAZ area, its perimeter and roundness, as well as the parafoveal vessel density (VD), were calculated by means of optical coherence tomography angiography in the superficial and deep vascular plexus. RESULTS: Glaucomatous eyes have no significant change in FAZ, its perimeter or the AI compared to healthy eyes. However, dividing the glaucomatous eye by visual field defect reveals that the eyes with a central defect have a significantly larger FAZ than those with a peripheral defect and the perimeter is also significantly larger. The AI shows no significant difference depending on the localisation of visual field defects. The macular/foveal VD is significantly lower in the ZDG group. CONCLUSIONS: In glaucoma, the FAZ enlarges when the visual field defect is centralised and VD decreases significantly in the area of fovea.


Asunto(s)
Glaucoma , Mácula Lútea , Angiografía con Fluoresceína , Fóvea Central , Glaucoma/diagnóstico por imagen , Glaucoma/patología , Humanos , Vasos Retinianos , Tomografía de Coherencia Óptica
13.
Adv Exp Med Biol ; 1213: 121-132, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32030667

RESUMEN

Early detection of glaucoma is important to slow down progression of the disease and to prevent total vision loss. Retinal fundus photography is frequently obtained for various eye disease diagnosis and record and is a suitable screening exam for its simplicity and low cost. However, the number of ophthalmologists who are specialized in glaucoma diagnosis is limited. We have been studying automated schemes for detection of nerve fiber layer defects and analysis of optic disc deformation, two major signs of glaucoma, in assisting ophthalmologists' accurate and efficient diagnosis. In this chapter, our recent progress in computerized methods is discussed.


Asunto(s)
Aprendizaje Profundo , Fondo de Ojo , Glaucoma/diagnóstico por imagen , Glaucoma/patología , Humanos , Fibras Nerviosas/patología , Disco Óptico/diagnóstico por imagen , Disco Óptico/patología
14.
Clin Imaging ; 61: 106-114, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32036260

RESUMEN

This study consists of an elastosonography evaluation of both eyes of 40 glaucomatous patients and 40 healthy subjects. We used shear wave elastography with a one-dimensional-array probe to capture two-dimensional images in order to study the optic nerve near the papilla, chorioretinal complex, lateral rectus muscle, and periorbital fat tissue. Furthermore, we used a two-dimensional array probe to capture three-dimensional images to study the optic nerve in toto with multilevel sampling. We obtained qualitative and quantitative data ("absolute" stiffness values). Then, we have investigated these tissue also measuring the "stiffness ratio" values. Statistically significant differences (p < 0.05), between glaucomatous patients and healthy patients, were noted in "absolute" stiffness values in the two-dimensional analysis at the emergence of the optic nerve and chorioretinal complex, and in the three-dimensional analysis at the emergence of the optic nerve (level I°). This result was supported by the statistically significant differences in the "stiffness ratio" values between the optic nerve and the adjacent adipose tissue, obtained both in two- and three-dimensional analyses. Data were subsequently compared with diagnostic tests currently used for glaucoma, which showed a sensitivity of 83% and specificity of 80% relative to those of elastosonography. We propose the use of elastosonography to verify the existence of pathological changes in the mechanical and elastic properties of peri-ocular structures and their variations as a complementary tool in the diagnosis of glaucoma and for follow-up during treatment.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Glaucoma/diagnóstico por imagen , Nervio Óptico/diagnóstico por imagen , Tejido Adiposo , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
15.
J Glaucoma ; 29(4): 287-294, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32053552

RESUMEN

PRéCIS:: A spectral-domain optical coherence tomography (SD-OCT) based deep learning system detected glaucomatous structural change with high sensitivity and specificity. It outperformed the clinical diagnostic parameters in discriminating glaucomatous eyes from healthy eyes. PURPOSE: The purpose of this study was to assess the performance of a deep learning classifier for the detection of glaucomatous change based on SD-OCT. METHODS: Three hundred fifty image sets of ganglion cell-inner plexiform layer (GCIPL) and retinal nerve fiber layer (RNFL) SD-OCT for 86 glaucomatous eyes and 307 SD-OCT image sets of 196 healthy participants were recruited and split into training (197 eyes) and test (85 eyes) datasets based on a patient-wise split. The bottleneck features extracted from the GCIPL thickness map, GCIPL deviation map, RNFL thickness map, and RNFL deviation map were used as predictors for the deep learning classifier. The area under the receiver operating characteristic curve (AUC) was calculated and compared with those of conventional glaucoma diagnostic parameters including SD-OCT thickness profile and standard automated perimetry (SAP) to evaluate the accuracy of discrimination for each algorithm. RESULTS: In the test dataset, this deep learning system achieved an AUC of 0.990 [95% confidence interval (CI), 0.975-1.000] with a sensitivity of 94.7% and a specificity of 100.0%, which was significantly larger than the AUCs with all of the optical coherence tomography and SAP parameters: 0.949 (95% CI, 0.921-0.976) with average GCIPL thickness (P=0.006), 0.938 (95% CI, 0.905-0.971) with average RNFL thickness (P=0.003), and 0.889 (0.844-0.934) with mean deviation of SAP (P<0.001; DeLong test). CONCLUSION: An SD-OCT-based deep learning system can detect glaucomatous structural change with high sensitivity and specificity.


Asunto(s)
Aprendizaje Profundo/clasificación , Glaucoma/clasificación , Glaucoma/diagnóstico por imagen , Tomografía de Coherencia Óptica , Adulto , Anciano , Área Bajo la Curva , Femenino , Glaucoma/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Fibras Nerviosas/patología , Disco Óptico/patología , Curva ROC , Células Ganglionares de la Retina/patología , Sensibilidad y Especificidad , Campos Visuales/fisiología
16.
J Glaucoma ; 29(5): 393-400, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32079996

RESUMEN

PRECIS: Glaucoma patients presented a decreased occipital pole surface area in both hemispheres. Moreover, these parameters are independently correlated with functional and structural ocular parameters. PURPOSE: The purpose of this study was to evaluate structural brain abnormalities in glaucoma patients using 3-Tesla magnetic resonance imaging and assess their correlation with associated structural and functional ocular findings. PATIENTS AND METHODS: This cross-sectional prospective study included 30 glaucoma patients and 18 healthy volunteers. All participants underwent standard automated perimetry, spectral-domain optical coherence tomography, and 3.0-Tesla magnetic resonance imaging. RESULTS: There was a significant difference between the surface area of the occipital pole in the left hemisphere of glaucoma patients (mean: 1253.9±149.3 mm) and that of control subjects (mean: 1341.9±129.8 mm), P=0.043. There was also a significant difference between the surface area of the occipital pole in the right hemisphere of glaucoma patients (mean: 1910.5±309.4 mm) and that of control subjects (mean: 2089.1±164.2 mm), P=0.029. There was no significant difference between the lingual, calcarine, superior frontal, and inferior frontal gyri of glaucoma patients and those of the control subjects (P>0.05 for all comparisons). The surface area of the occipital pole in the left hemisphere was significantly correlated with perimetry mean deviation values, visual acuity, age, and retinal nerve fiber layer thickness (P=0.001, <0.001, 0.010, and 0.006, respectively). The surface area of the occipital pole in the right hemisphere was significantly correlated with perimetry mean deviation values, visual field indices, visual acuity, age, and retinal nerve fiber layer thickness (P<0.001, 0.007, <0.001, 0.046, and <0.001, respectively). CONCLUSION: Glaucoma patients presented a decreased occipital pole surface area in both hemispheres that independently correlated with functional and structural ocular parameters.


Asunto(s)
Encefalopatías/diagnóstico por imagen , Glaucoma/diagnóstico por imagen , Imagen por Resonancia Magnética , Lóbulo Occipital/diagnóstico por imagen , Adulto , Anciano , Encefalopatías/fisiopatología , Estudios Transversales , Femenino , Glaucoma/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Fibras Nerviosas/patología , Lóbulo Occipital/fisiopatología , Estudios Prospectivos , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
17.
Sci Rep ; 10(1): 3027, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-32080343

RESUMEN

Although early glaucoma detection is important to prevent visual loss due to disease progression, its clinical diagnosis in highly myopic eyes is still difficult. Many studies using optical coherence tomography (OCT) angiography (OCTA) reported decreased vessel density (VD) in glaucomatous eyes compared to normal eyes. We evaluated the diagnostic ability of peripapillary VD and macular VD measured by OCTA, comparing them with conventional valuables such as peripapillary retinal nerve fibre layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness measured by OCT. We also calculated the average VD ratio (VDR) (average outer macular VD/average inner macular VD), superior VDR (superior outer macular VD/average inner macular VD), and inferior VDR (inferior outer macular VD/average inner macular VD). Totally, 169 eyes from 169 subjects were enrolled. Among OCTA measurements, the best diagnostic parameters were average VDR (AUROC: 0.852 and 0.909) and inferior VDR (AUROC: 0.820 and 0.941) in nonhighly and highly myopic eyes, respectively. Inferior VDR showed better diagnostic ability than most of the other OCT measurements including peripapillary RNFL thickness and macular GCIPL thickness in highly myopic eyes. Accordingly, OCTA measurements can be useful for diagnosing glaucoma in highly myopic eyes, especially when using calculated indices such as average VDR or inferior VDR.


Asunto(s)
Angiografía , Glaucoma/diagnóstico por imagen , Glaucoma/diagnóstico , Miopía/diagnóstico por imagen , Miopía/diagnóstico , Vasos Retinianos/diagnóstico por imagen , Tomografía de Coherencia Óptica , Área Bajo la Curva , Femenino , Glaucoma/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Miopía/complicaciones , Curva ROC
18.
Sci Rep ; 10(1): 402, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31941958

RESUMEN

This study describes a segmentation-free deep learning (DL) algorithm for measuring retinal nerve fibre layer (RNFL) thickness on spectral-domain optical coherence tomography (SDOCT). The study included 25,285 B-scans from 1,338 eyes of 706 subjects. Training was done to predict RNFL thickness from raw unsegmented scans using conventional RNFL thickness measurements from good quality images as targets, forcing the DL algorithm to learn its own representation of RNFL. The algorithm was tested in three different sets: (1) images without segmentation errors or artefacts, (2) low-quality images with segmentation errors, and (3) images with other artefacts. In test set 1, segmentation-free RNFL predictions were highly correlated with conventional RNFL thickness (r = 0.983, P < 0.001). In test set 2, segmentation-free predictions had higher correlation with the best available estimate (tests with good quality taken in the same date) compared to those from the conventional algorithm (r = 0.972 vs. r = 0.829, respectively; P < 0.001). Segmentation-free predictions were also better in test set 3 (r = 0.940 vs. r = 0.640, P < 0.001). In conclusion, a novel segmentation-free algorithm to extract RNFL thickness performed similarly to the conventional method in good quality images and better in images with errors or other artefacts.


Asunto(s)
Algoritmos , Aprendizaje Profundo , Glaucoma/patología , Procesamiento de Imagen Asistido por Computador/métodos , Fibras Nerviosas/patología , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Estudios de Casos y Controles , Estudios Transversales , Femenino , Glaucoma/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Campos Visuales
19.
Sci Rep ; 10(1): 779, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31964909

RESUMEN

The study subjects were residents of Chikusei city, Japan, aged 40 years or older who attended annual health check-up programs and participated in the JPHC-NEXT Eye Study which performed non-mydriatic fundus photography of both eyes. The relationship of glaucomatous fundus changes such as optic disc cupping (cup to disc ratio ≥ 0.7) and retinal nerve fiber layer defect (NFLD) with the presence of epiretinal membrane (ERM) were examined cross-sectionally. A total of 1990 persons gave consent to participate in this study in 2013. The overall prevalence of ERM was 12.9%. Of these, 1755 had fundus photographs of sufficient quality and no history of intraocular surgery (mean age: 62.3 ± 10.0 years). After adjusting for age, sex and refractive error, NFLD was positively associated with the presence of ERM (odds ratio [OR]: 2.48; 95% confidence interval [CI]: 1.24, 4.96; P = 0.010), but optic disc cupping was not (OR: 1.33; CI: 0.71, 2.48; P = 0.37). The results did not necessarily suggest an association between glaucoma and ERM, but indicated an association between NFLD and ERM.


Asunto(s)
Membrana Epirretinal/epidemiología , Glaucoma/epidemiología , Fibras Nerviosas/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Membrana Epirretinal/diagnóstico por imagen , Membrana Epirretinal/patología , Femenino , Glaucoma/diagnóstico por imagen , Glaucoma/patología , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Disco Óptico/diagnóstico por imagen , Prevalencia
20.
PLoS One ; 15(1): e0227602, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31990918

RESUMEN

OBJECTIVES: To provide in vivo measurements of anterior chamber angle structures and their relationship with age as evaluated by high-frequency ultrasound biomicroscopy (UBM) in patients with primary congenital glaucoma (PCG). METHODS: High-frequency UBM was done for 51 PCG eyes from 40 patients (aged from 3 to 96 months) and 11 unaffected contralateral eyes. Parameters, including the proportion of observable abnormal tissue membrane and Schlemm's canal, the largest cross-sectional area (CSA) of Schlemm's canal (SC), SC meridional diameter, trabecular-iris angle (TIA), trabecular meshwork (TM) thickness, iris thickness, ciliary process length, and corneal limbus thickness were compared between the two groups and their relationship with age was explored in PCG eyes. RESULTS: Abnormal tissue membrane was detected in 27.5% of PCG eyes and none in unaffected eyes. SC was observed in 73.1% of PGC eyes compared to 100% in unaffected eyes (P<0.001). The largest CSA of SC, SC meridional diameter, iris thickness, and corneal limbus thickness were all significantly smaller in PCG eyes compared to unaffected eyes (all P<0.05). TIA and ciliary process length in unaffected eyes were smaller than PCG eyes (both P<0.05). The largest CSA of SC, TM thickness, iris thickness, and ciliary process length were all significantly correlated to age in PCG eyes (P<0.05). CONCLUSIONS: The anatomical information evaluated by high-frequency UBM may provide glaucoma specialists a useful tool to aid in understanding the dysgenesis and changes with age of anterior chamber angle in PCG.


Asunto(s)
Cámara Anterior/diagnóstico por imagen , Glaucoma/diagnóstico por imagen , Microscopía Acústica/métodos , Factores de Edad , Cámara Anterior/patología , Niño , Preescolar , Cuerpo Ciliar/diagnóstico por imagen , Femenino , Glaucoma/congénito , Glaucoma/patología , Humanos , Lactante , Masculino , Variaciones Dependientes del Observador , Malla Trabecular/diagnóstico por imagen , Ultrasonografía
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