Validity and reproducibility of retinal arteriole and venule diameter measurements: ELSA-Brasil study. A cross-sectional study

ABSTRACT BACKGROUND: Investigation of alterations to retinal microvasculature may contribute towards understanding the role of such changes in the pathophysiology of several chronic non-communicable diseases. The objective here was to evaluate the validity and reproducibility of retinal arteriole and venule diameter measurements made by Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) graders. DESIGN AND SETTING: Cross-sectional study at six teaching and research institutions. METHODS: To evaluate validity, each of 25 retinal images from the University of Wisconsin (gold standard) was measured by five ELSA-Brasil graders. To evaluate reproducibility, 105 images across the spectrum of vessel diameters were selected from 12,257 retinal images that had been obtained between 2010 and 2012, and each image was reexamined by the same grader and by an independent grader. All measurements were made using the Interactive Vessel Analysis (IVAN) software. Bland-Altman plots, paired t tests and intraclass correlation coefficients (ICCs) were analyzed. RESULTS: Mean differences between ELSA-Brasil and gold-standard readings were 0.16 µm (95% CI -0.17-0.50; P = 0.31) for central retinal artery equivalent (CRAE), -0.21 µm (95% CI -0.56-0.14; P = 0.22) for central retinal vein equivalent (CRVE) and 0.0005 (95% CI -0.008-0.009; P = 0.55) for arteriole/venule ratio (AVR). Intragrader ICCs were 0.77 (95% CI 0.67-0.86) for CRAE, 0.90 (95% CI 0.780.96) for CRVE and 0.70 (0.55-0.83) for AVR. Intergrader ICCs were 0.75 (95% CI 0.64-0.85) for CRAE, 0.90 (95% CI 0.79-0.96) for CRVE and 0.68 (95% CI 0.55-0.82) for AVR. CONCLUSIONS: Retinal microvascular diameter measurements are valid and present moderate to high intra and intergrader reproducibility in ELSA-Brasil.

Teledermatology protocol for screening of Skin Cancer

BACKGROUND: Telemedicine refers to the use of technology as improvement of healthcare delivery to places where distance becomes an obstacle. Its use represents a great potential for dermatology, a specialty whose visual analysis phase is essential in diagnosis. OBJECTIVES: To analyze the compatibility index of skin cancer diagnoses between primary care and teledermatology, and to validate a protocol for standardization of digital imaging to obtain the reports in teledermatology. METHODS: An observational cross-sectional study developed through the census of 333 examination requests, received between January/2012 and July/2012, in the Center for Telemedicine and Telehealth of SES-SC. We used a protocol for photographic lesion standardization, consisting of three steps (panoramic photo, close-up with ruler and dermoscopy). After collection, the data were sent to a virtual site on the Internet, and recorded with the use of an electronic health record containing the images, the skin phototype and demographic characteristics. RESULTS: The level of compatibility between the diagnosis of skin cancer in Santa Catarina's primary care and the diagnosis proposed by teledermatology was 19.02%. Proportionally, it was 21.21% for BCC, 44.44% for SCC and 6.98% for MM. The protocol was statistically significant (p <0.05), with an OR of 38.77. CONCLUSION: The rate of diagnostic compatibility of skin cancer was low and the use of the protocol optimized the chance of validating requests for examination. .

Cribado de retinopatía diabética mediante retinografía midriática en atención primaria / Coverage and results of a screening program for diabetic retinopathy using mydriatic retinography in primary health care

OBJETIVOS: Conocer la cobertura de un programa de cribado de retinopatía diabética en atención primaria y la concordancia entre médicos de familia (MF) y oftalmólogos. MATERIAL Y MÉTODOS: Estudio observacional transversal. Revisión de retinografías midriáticas de pacientes con diabetes mellitus tipo 2 (2007-2008) solicitadas por MF de tres centros de salud urbanos en Jaén,España. RESULTADOS: En total 296 retinografías (2007) y 380 (2008) (cobertura=26 por ciento±2.4).Retinografías patológicas: 181 MF (27 por ciento±1.3) y 59 (9 por ciento±0.3) oftalmólogos. Concordancia global moderada (kappa=0.408±0.039), que mejora del primer al segundo año (0.34 y 0.45; p<0.001, prueba χ2). La interpretación de los MF tiene sensibilidad, 97 por ciento, especificidad, 80 por ciento, VPP, 33 por ciento, VPN, 100 por ciento, cociente de probabilidad positivo, 4.88 y negativo, 0.04. Hay variabilidad en cobertura y concordancia entre centros de salud. CONCLUSIONES: La retinografía midriática realizada e interpretada por MF es útil como cribado de retinopatía en diabéticos. En el segundo año se mejora cobertura, valores predictivos y cocientes de probabilidad, aunque se debe homogeneizar la interpretación.

OBJECTIVE: To identify the coverage of a diabetic retinopathy screening program in primary health care and to assess agreement between ophthalmologists and family physicians (FP) regarding retinography evaluations of diabetic patients. MATERIALS AND METHODS: Cross-sectional observational study,with a review of diabetic patients' mydriatic retinographies (2007-2008) from three urban primary health centers (PHC)(Jaén-Spain). RESULTS: A total of 296 retinographies in 2007 and 380 in 2008 (coverage=26 percent±2,4) were reviewed. Pathological retinographies were identified by 181 FPs (27 percent±1,3) and 59 (9 percent±0,3) ophthalmologists.Total agreement was moderate (kappa=0,408±0,039).Agreement was better in the latter year (0,45 vs 0,34; p<0,001 test χ2). FP evaluations showed 97 percent sensitivity,80 percent specificity,33 percent positive predictive value, 100 percent negative predictive value, 4, 88 positive likelihood ratio and 0,04 negative likelihood ratio. We find variability in coverage and agreement between PHC. CONCLUSIONS: Mydriatic retinographies performed and evaluated by FPs are useful to retinopathy screening of diabetic patients. Coverage, predictive values and likelihood ratio were better in the latter year, although the interpretation should be homogenized.

Sistema automático para quantificação e visualização da aeração pulmonar em imagens de tomografia computadorizada de tórax: Sistema de Análise de Imagens Pulmonares – SAIP / Automatic system for quantification and visualization of lung aeration on chest computed tomography images: the Lung Image System Analysis – LISA

A tomografia computadorizada de alta resolução (TCAR) é o exame de escolha na avaliação diagnóstica de afecções do parênquima pulmonar. Neste particular, há um interesse crescente por sistemas computacionais capazes de analisar automaticamente a densidade radiológica dos pulmões. O principal objetivo deste trabalho é apresentar um sistema automático para quantificação e visualização do grau de aeração pulmonar (SAIP), em imagens de TCAR de pulmões com diferentes graus de alterações da aeração pulmonar. Como objetivo secundário comparar o SAIP ao sistema Osiris e a um algoritmo específico de segmentação pul­monar (SP), quanto à acurácia na segmentação do parênquima pulmonar. O SAIP disponibiliza atributos quantitativos extraídos automaticamente, tais como perímetro, área e volume da secção pulmonar, bem como o histograma de faixa de densidades ra­diológicas e acumulado, densidade pulmonar média (Dpm) em unidades Hounsfield (UH), área relativa dos voxels com densi­dade menor que –950 UH (RA950) e os valores de 15° percentil de baixa atenuação (PERC15). Além disso, é capaz de processar imagens por meio de uma ferramenta de máscara colorida, que aplica pseudo­cores no parênquima pulmonar, conforme faixas de densidade radiológicas pré­determinadas. Os resultados da segmentação pulmonar são comparados para um conjunto de 102 imagens de 8 voluntários saudáveis e 141 imagens de 11 pacientes com doença pulmonar obstrutiva crônica (DPOC). Quanto à segmentação, o SAIP se apresenta mais efetivo do que os outros dois métodos. O SAIP constitui uma ferramenta pro­missora no auxílio ao diagnóstico de enfisema em pacientes com DPOC, com grande potencial de aplicação nesta área e em outras doenças pulmonares.

High Resolution Computed Tomography (HRCT) is the exam of choice for the diagnostic evaluation of lung parenchyma diseases. There is an increasing interest for computational systems able to automatically analyze the radiological densities of the lungs in CT images. The main objective of this study is to present a system for the automatic quantification and visualization of the lung aeration in HRCT images of different degrees of aeration, called Lung Image System Analysis (LISA). The secondary objective is to compare LISA to the Osiris system and also to specific algorithm lung segmentation (ALS), on the accuracy of the lungs segmentation. The LISA system automatically extracts the following image attributes: lungs perimeter, cross sectional area, volume, the radiological densities histograms, the mean lung density (MLD) in Hounsfield units (HU), the relative area of the lungs with voxels with density values lower than –950 HU (RA950) and the 15th percentile of the least density voxels (PERC15). Furthermore, LISA has a colored mask algorithm that applies pseudo-colors to the lung parenchyma according to the pre-defined radiological density chosen by the system user. The lungs segmentations of 102 images of 8 healthy volunteers and 141 images of 11 patients with Chronic Obstructive Pulmonary Disease (COPD) were compared on the accuracy and concordance among the three methods. The LISA was more effective on lungs segmentation than the other two methods. LISA's color mask tool improves the spatial visualization of the degrees of lung aeration and the various attributes of the image that can be extracted may help physicians and researchers to better assess lung aeration both quantitatively and qualitatively. LISA may have important clinical and research applications on the assessment of global and regional lung aeration and therefore deserves further developments and validation studies.

Quantificaçäo das fibras musculares lisas penianas por histomorfometria computadorizada em pacientes com disfunçäo erétil grave / Computerized image analysis of penile smooth muscle fibers in severe erectile dysfunction patients

A fibra muscular lisa apresenta fundamental importância no mecanismo de ereção e alterações em sua função ou em sua quantidade podem estar associadas à disfunção erétil. O objetivo do estudo é analisar a proporção de fibras musculares lisas em 20 pacientes com disfunção erétil grave de acordo com o índice Internacional de Função Erétil e Teste de Ereção Fármaco-induzida divididos em dois grupos de 10 pacientes, sendo um com fluxo arterial normal (44 a 78 anos, média @ 63 anos) e o outro com fluxo arterial alterado (38 a 67 anos, média @ 56,2 anos) ao duplex ultra-som. Os resultados são comparados com um grupo formado por 10 cadáveres de 18 a 25 anos (média =- 21,6 anos) presumidamente potentes. A quantificação das fibras musculares lisas foi realizada a partir de estudo imunohistoquímico com anticorpo anti-actina e análise computadorizada da imagem pelo sistema HSL (matiz, saturação e luminosidade). A proporção de fibras musculares lisas encontradas foi de 41,15 por cento para o grupo controle. Os pacientes com disfunção erétil apresentaram 27,24 por cento de fibras musculares lisas para o grupo com fluxo arterial normal e 25,74 por cento para o grupo com fluxo arterial insuficiente. Com exceção de apenas um paciente (do grupo com fluxo arterial normal), 19 pacientes apresentavam ao menos uma doença crônica ou fator de risco para disfunção erétil, destacando-se diabetes mellitus, hipertensão arterial sistêmica e tabagismo, nesta ordem. Concluímos que nos pacientes com disfunção erétil grave o fluxo arterial isoladamente não apresenta interferência na proporção de fibras musculares lisas, pois os resultados foram semelhantes. Nestes pacientes com doença grave, a diminuição das fibras musculares lisas em relação ao grupo controle, pode decorrer das doenças crônicas e de seu potencial aterosclerótico