Identifying and understanding optical coherence tomography artifacts that may be confused with glaucoma / Identificando e compreendendo os artefatos de tomografia de coerência óptica que podem ser confundidos com o glaucoma

ABSTRACT Optical coherence tomography is often used for detection of glaucoma as well as to monitor progression. This paper reviews the most common types of artifacts on the optical coherence tomography report that may be confused with glaucomatous damage. We mainly focus on anatomy-related artifacts in which the retinal layer segmentation and thickness measurements are correct. In such cases, the probability maps (also known as deviation maps) show abnormal (red and yellow) regions, which may mislead the clinician to assume disease is present. This is due to the anatomic variability of the individual, and the normative database must be taken into account.

RESUMO A tomografia de coerência óptica é frequentemente usada para detectar glaucoma, bem como para monitorar a progressão. Este artigo analisa os tipos mais comuns de artefatos no relatório de tomografia de coerência óptica que podem ser confundidos com danos glaucomatosos. Nós nos concentramos principalmente nos artefatos relacionados à anatomia em que a segmentação da camada da retina e as medidas de espessura estão corretas. Nesses casos, os mapas de probabilidade (também conhecidos como mapas de desvio) mostram regiões anormais (vermelho e amarelo), o que pode induzir o clínico em erro ao supor que a doença está presente. Isto se deve à variabilidade anatômica do indivíduo, e o banco de dados normativo deve ser levado em conta.

Use of computerized campimetry and/or optical coherence tomography for glaucoma diagnosis by non-glaucoma specialists / Uso da campimetria e/ou da tomografia de coerência óptica no diagnóstico do glaucoma por oftalmologistas generalistas

ABSTRACT Purpose: To compare the use of visual field and/or optical coherence tomography (OCT) combined with color retinography by non-glaucoma specialists for differentiating glaucoma from physiological cupping. Methods: Eighty patients with glaucoma or physiological cupping (40 of each) were randomized according to the examination used (GI: color retinography, GII: color retinography + visual field, GIII: color retinography + optical coherence tomography, GIV: color retinography + visual field + optical coherence tomography). Twenty non-specialist ophthalmologists diagnosed glaucoma from PowerPoint slide images, without direct patient examination. Results: Inter-examiner agreement was good for GII (ĸ: 0.63; 95%CI, 0.53-0.72), moderate for GIII (ĸ: 0.58; 95%CI, 0.48-0.68) and GIV (ĸ: 0.41; 95%CI, 0.31-0.51), and low for GI (ĸ: 0.30; 95%CI, 0.20-0.39) (p<0.001). Diagnostic accuracy was higher in GIII (15.8 ± 1.82) than GI (12.95 ± 1.46, p<0.001) and higher in GII (16.25 ± 2.02) than GI and GIV (14.10 ± 2.24) (both p<0.001). For glaucoma patients only, diagnostic accuracy in GII and GIII was superior to that in GI and GIV (both p<0.001). Sensitivity and specificity were 59% and 70.5% in GI; 86.5% and 76% in GII, 86.5% and 71.5% in GIII; and 68.5% and 72.5% in GIV, respectively. Accuracy was highest in GII (81.3% [95%CI, 77.1-84.8]), followed by GIII (79% [95%CI, 74.7-82.7]), GIV (70,5% [95%CI, 65.9-74.8]), and GI (64.8% [95%CI, 60.0-69.3]). Conclusions: Non-glaucoma specialists could not differentiate glaucoma from increased physiological cupping when using color retinography assessment alone. Diagnostic accuracy and inter-rater agreement improved significantly with the addition of visual field or optical coherence tomography. However, the use of both modalities did not improve sensitivity/specificity.(AU)

RESUMO Objetivos: Verificar a influência do campo visual e/ou tomografia de coerência óptica, quando analisados em associação à retinografia colorida, na diferenciação entre indivíduos com glaucoma daqueles com aumento fisiológico de escavação. Métodos: Oitenta pacientes com glaucoma ou aumento fisiológico de escavação (40 cada) foram randomizados de acordo com o exame testado (GI: retinografia colorida, GII: retinografia colorida + campo visual, GIII: retinografia colorida + tomografia de coerência óptica, GIV: retinografia colorida + campo visual + tomografia de coerência óptica). Vinte oftalmologistas não especialistas em glaucoma diagnosticaram glaucoma através de slides do PowerPoint, sem o exame direto do paciente. Resultados: A concordância interexaminador foi boa para o GII (ĸ: 0,63; 95%CI, 0,53-0,72), moderada para GIII (ĸ: 0,58; 95%CI, 0,48-0,68) e GIV (ĸ: 0,41; 95%CI, 0,31-0,51), e baixa para o GI (ĸ: 0,30; 95%CI, 0,20-0,39) (p<0,001). Acurácia diagnostica foi maior no GIII (15,8 ± 1,82) em comparação ao GI (12,95 ± 1,46, p<0,001) e o GII (16,25 ± 2,02) maior em comparação ao GI e GIV (14,10 ± 2,24) (para ambos, p<0,001). Para os pacientes com glaucoma, a acurácia diagnostica nos grupos GII e GIII foi superior do que em GI e GIV (ambos p<0,001). Sensibilidade e especificidade foram 59% e 70,5% no GI; 86,5% e 76% no GII, 86,5% e 71,5% no GIII; 68,5% e 72,5% no GIV, respectivamente. A acurácia foi maior no GII (81,3% [95%CI, 77,1-84,8]), seguido pelo GIII (79% [95%CI, 74,7-82,7]), GIV (70,5% [95%CI, 65,9-74,8]), e GI (64,8% [95%CI, 60,0-69,3]). Conclusões: A avaliação isolada da retinografia colorida por oftalmologistas não especialistas em glaucoma não pode diferenciar pacientes com glaucoma daqueles com aumento fisiológico de escavação. Houve aumento da acurácia diagnóstica e da concordância interobservador com o acréscimo do campo visual ou da tomografia de coerência óptica. Entretanto, o uso de ambas as modalidades não melhorou a sensibilidade/especificadade.(AU)

Trabéculo-trabeculectomía como tratamiento quirúrgico inicial del glaucoma congénito primario / Trabeculotomy-trabeculectomy as initial surgical treatment for primary congenital glaucoma

El glaucoma congénito primario constituye la forma más común de glaucoma infantil, el cual exige un diagnóstico precoz y un tratamiento quirúrgico relativamente urgente, ya que puede ocasionar graves secuelas morfológicas y funcionales. Se presenta la realización, por primera ocasión, de la trabéculo-trabeculectomía combinada en la República Democrática y Popular de Argelia. Se ejecutó en un paciente árabe, de un año de edad, a quien se le diagnosticó el glaucoma congénito primario II. Se evaluó el seguimiento posoperatorio con resultados satisfactorios, por lo que se consideró la trabéculo-trabeculectomía como el proceder quirúrgico efectivo y suficientemente seguro, el cual debe ser realizado por un personal calificado para poder admitirse como primera opción en el tratamiento quirúrgico del glaucoma congénito primario(AU)

Primary congenital glaucoma is the most common form of childhood glaucoma. This condition requires early diagnosis and relatively urgent surgical treatment, since it may leave serious morphological and functional sequelae. A description is provided of the first combined trabeculotomy-trabeculectomy performed in the People's Democratic Republic of Algeria. The operation was performed on a male one-year-old Arab patient diagnosed with primary congenital glaucoma II. Post-operative follow-up found satisfactory results, and trabeculotomy-trabeculectomy was thus considered to be an effective, sufficiently safe surgical procedure, which should be performed by qualified personnel to be accepted as the first surgical treatment option for primary congenital glaucoma(AU)

Joint optic disc and cup segmentation based on residual multi-scale fully convolutional neural network / 生物医学工程学杂志

Glaucoma is the leading cause of irreversible blindness, but its early symptoms are not obvious and are easily overlooked, so early screening for glaucoma is particularly important. The cup to disc ratio is an important indicator for clinical glaucoma screening, and accurate segmentation of the optic cup and disc is the key to calculating the cup to disc ratio. In this paper, a full convolutional neural network with residual multi-scale convolution module was proposed for the optic cup and disc segmentation. First, the fundus image was contrast enhanced and polar transformation was introduced. Subsequently, W-Net was used as the backbone network, which replaced the standard convolution unit with the residual multi-scale full convolution module, the input port was added to the image pyramid to construct the multi-scale input, and the side output layer was used as the early classifier to generate the local prediction output. Finally, a new multi-tag loss function was proposed to guide network segmentation. The mean intersection over union of the optic cup and disc segmentation in the REFUGE dataset was 0.904 0 and 0.955 3 respectively, and the overlapping error was 0.178 0 and 0.066 5 respectively. The results show that this method not only realizes the joint segmentation of cup and disc, but also improves the segmentation accuracy effectively, which could be helpful for the promotion of large-scale early glaucoma screening.

Caracterización de indicadores de detección de glaucoma con los equipos OCT Spectralis y campímetro Humphrey II en pacientes altos miopes y altos miopes glaucomatosos del Hospital Clínico Universidad de Chile / Characterization of glaucoma detection indicators with OCT Spectralis equipment and Humphrey II campimeter in patients with high myopia and high myopia glaucomatous at the Hospital Clínico Universidad de Chile

Purpose: Characterize and describe glaucoma index parameters of the results of visual exams, Optical Coherence Tomography and Visual Field, in high myopic subjects with and without the pathology. Method: Cross sectional and observational study of 39 eyes, 15 high myopic with glaucoma y 24 high myopic without it. Visual Field (VF) were performed, where the global index between both groups were analyzed; Mean Deviation (MD), Model Standard Deviation (MSD) and Visual Field Index (VFI), beside Optical Coherence Tomography (OCT), in which the thickness of the ganglion cells layer (GCL) inside 3 central mm was compared. Results: The results were satisfactory, demonstrating different characteristics between the high myopic group with glaucoma and without it, both in VF and OCT exams. It was obtained in the VF analysis difference in average MD of -4,92 dB + 3,71 (p<0,05); difference in average DSM of 2,01 dB + 2,85 (p>0,05) and VFI with Friedman Test 10,29 (p>0,05). The statistical OCT analysis, when comparing GCL, observed that the Temporary sector (T) had a statistically significant decrease (p<0,05). Conclusions: To continue studies in this investigative line, can expand the knowledge in this area, mainly in the study of the GCL. (AU)

Angiografía por tomografía de coherencia óptica: una nueva herramienta diagnóstica / Optical coherence tomography angiography: a new diagnostic tool

Objetivo: Realizar una revisión de la literatura sobre angiografía por tomografía de coherencia óptica (OCT-A), sus principales características y potenciales usos como herramienta diagnostica en oftalmología. Diseño del estudio: Revisión de la literatura. Método: Búsqueda de la literatura electrónica en PUBMED, Scopus y Google Scholar. Conclusión: La tomografía de coherencia óptica (OCT) ha revolucionado el manejo tanto de la patología retiniana como el diagnóstico del glaucoma. La angiografía por OCT (OCT-A), es una técnica de no contacto, no invasiva que utiliza múltiples algoritmos para la detección del flujo sanguíneo permitiendo la visualización en alta resolución de imágenes angiográficas volumétricas de la retina. Esta revisión, resalta las características diferenciales existentes entre los distintos métodos de angiografía disponibles en la actualidad y realiza una revisión de la literatura disponible sobre sus aplicaciones como: retinopatía diabética (RD), degeneración macular relacionada con la edad (DMRE), oclusiones vasculares retinianas (OVR) y glaucoma.

Purpose: To perform a review of the available literature on angiography by optical coherence tomography (OCT-A) its main characteristics and potential uses as a diagnostic tool in ophthalmology. Study Design: Literature Review. Method: A literature search was made in PUBMED, Scopus and Google Scholar. Conclusion: Optical coherence tomography (OCT) has transformed the approach to diagnosis and management of retinal pathology and glaucoma. Recently this technology has also been the object of constant improvement, therefore OCT (OCT-A) angiography can now be performed, which is a noninvasive technique that uses multiple algorithms of fl ow detection allowing the visualization of volumetric images of the retina. The differential characteristics existing between the angiographic methods currently available are denoted below. A review of the available literature on the subject and its applications in ophthalmic pathologies of the retina such as: diabetic retinopathy (RD), age-related macular degeneration (AMD), retinal vascular occlusions (OVR), and glaucoma.

Uso clínico del tomógrafo de coherencia óptica Spectralis en la evaluación del glaucoma / Use of the Spectralis optical coherence tomography scanner to evaluate glaucoma

La evolución reciente de las herramientas de imagen ha mejorado notablemente la determinación objetiva y cuantitativa de los cambios estructurales en el glaucoma. El tomógrafo de coherencia óptica de dominio espectral, disponible comercialmente, y su módulo Glaucoma Premium Edition recientemente incorporado, ofrece beneficios en la evaluación del glaucoma, por presentar una mayor resolución axial, velocidades de exploración más rápidas, reproducibilidad mejorada, compensación de movimientos oculares, supresión de interferencia y algoritmos avanzados de segmentación. La presente revisión describe las características técnicas, los parámetros de fiabilidad, los protocolos de estudio, la interpretación de los resultados y los principales artefactos que afectan sus medidas. Esta información permite a la comunidad médica realizar un uso y una evaluación adecuada de esta tecnología, y en consecuencia ajustar la gestión clínica según sea necesario(AU)

The recent evolution of imaging tools has notably improved the objective, quantitative determination of structural changes in the glaucoma. The spectral domain optical coherence tomography scanner, commercially available, and its recently incorporated Glaucoma Module Premium Edition, facilitate evaluation of the glaucoma, due to their greater axial resolution, faster exploration speeds, improved reproducibility, eye movement compensation, interference suppression, and advanced segmentation algorithms. The present review describes the technical features, reliability parameters, study protocols, interpretation of results and main artifacts affecting its measurements. Such information will make it possible for the medical community to adequately use and evaluate this technology, adjusting clinical management as required(AU)

Glaucoma secundario a presión venosa epiescleral elevada en síndrome de Crest / Secondary glaucoma as elevated episcleral venous pressure in Crest syndrome

El glaucoma secundario a presión venosa epiescleral elevada asociada a enfermedad de Crest es una entidad rara, frecuentemente refractaria a la terapia médica y quirúrgica. Debemos ser exhaustivos en la anamnesis, en la exploración y en la solicitud de exámenes de imagen en aras de encontrar la posible causa para lograr un manejo exitoso del paciente con esta enfermedad, tanto desde el punto de vista sistémico como oftalmológico. La cirugía antiglaucomatosa puede ser complicada en estos casos(AU)

Secondary glaucoma as elevated episcleral venous pressure associated to Crest syndrome is a rare condition often refractory to clinical or surgical therapy. Exhaustive anamnesis, exploration and imaging should be conducted to find the possible cause and thus implement successful management of the sufferer, both systemically and ophthalmologically. Glaucoma surgery may be complicated in these cases(AU)

Secondary glaucoma induced by bilateral acute depigmentation of the iris / Glaucoma secundário à despigmentação bilateral aguda da íris

Abstract We report a case of a middle-aged woman who developed acute, bilateral, symmetrical, slightly transilluminating depigmentation of the iris and pigment discharge into the anterior chamber following the use of oral moxifloxacin for bacterial sinusitis. She had been misdiagnosed as having autoimmune uveitis, treated with steroids and tropicamide, and underwent severe ocular hypertension and glaucoma despite posterior correct diagnosis.

Resumo Relato de um caso de uma paciente do sexo feminino de meia idade que desenvolveu despigmentação bilateral simultânea aguda com dispersão de pigmentos na câmara anterior e discreta transiluminação após o uso de moxifloxacino oral para tratamento de sinusite bacteriana. Ela Havia sido diagnosticada com uveite autoimune e tratada com corticosteroide tópico e tropicamida e evoluiu com hipertensão ocular grave e glaucoma apesar de ,posteriormente, o diagnóstico ter sido correto.

Comparison of linear measurements of optic cup-to-disk ratio obtained with RTVue OCT and digital retinography / Comparação entre as medidas lineares da relação escavação/disco óptico obtidas com o OCT RTVue e a retinografia digital

ABSTRACT Purpose: To compare the linear measurements of the optic disk cup obtained using RTVue optical coherence tomography (OCT) with those obtained using digital retinography. Methods: This is a cross-sectional study performed with digital retinography and RTVue OCT images from patients with glaucoma or patients suspected of glaucoma. In color retinography, the greatest horizontal and vertical diameters of the optic disk starting from the inner edge of the Elschnig ring were obtained using a pachymeter with a grade of 0.01 mm. In OCT, the delineation of the optic nerve was obtained automatically from the horizontal and vertical cup results. Results: One hundred eyes from 100 subjects with a mean age of 60.1 ± 15.7 years were included. Of these, 79 were the right eye and 21 the left eye, with 61 men and 39 women. The mean horizontal cup obtained with OCT was 0.91 ± 0.10, while that obtained with retinography was 0.79 ± 0.11 (p<0.01). Conclusions: There was poor agreement between the evaluated methods in the measurements of optic disk cup excavations. Measurements obtained automatically with OCT RTVue were higher but were significantly correlated with measurements obtained manually with digital retinography. Poor agreement of the optic disk parameters between the two imaging devices was noted.

RESUMO Objetivo: Comparar as medidas lineares da escavação do disco óptico, obtidas com o OCT RTVue com as obtidas pela retinografia digital. Métodos: Trata-se de um estudo transversal. Utilizou-se imagens de retinografia digital e exames de OCT obtidos pelo aparelho RTVue de pacientes suspeitos ou com glaucoma. Na retinografia colorida, foram obtidos os maiores diâmetros horizontal e vertical do disco óptico, a partir da borda interna do Anel de Elschnig através de paquímetro com graduação de 0,01 mm. No OCT, a delineação do nervo óptico foi obtida automaticamente e a partir dos resultados foi registrado o diâmetro horizontal e vertical da escavação. Resultados: Foram incluídos 100 olhos de 100 indivíduos, com idade média de 60,1 ± 15,7 anos. Desses, 79 foram do olho direito e 21 do olho esquerdo, sendo 61 homens e 39 mulheres. Verificou-se que as médias das escavações horizontais obtidas com o OCT foram de 0,91 ± 0,10, enquanto que as obtidas pela retinografia foram 0,79 ± 0,11 (p<0,01). Conclusões: Nota-se fraca concordância entre os métodos avaliados para quantificar as medidas das escavações do disco óptico. As medidas obtidas automaticamente pelo OCT RTVue foram maiores, porém correlacionadas com as medidas obtidas manualmente pela retinografia digital. Além disso, notou-se fraca concordância nos parâmetros do disco óptico entre os dois dispositivos de imagens.