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Purpose: This paper explores different machine learning (ML) algorithms for analyzing diffusion nuclear magnetic resonance imaging (dMRI) models when analytical fitting shows restrictions. It reviews various ML techniques for dMRI analysis and evaluates their performance on different b-values range datasets, comparing them with analytical methods. Materials and Methods: After standard fitting for reference, four sets of diffusion-weighted nuclear magnetic resonance images were used to train/test various ML algorithms for prediction of diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), and kurtosis (K). ML classification algorithms, including extra-tree classifier (ETC), logistic regression, C-support vector, extra-gradient boost, and multilayer perceptron (MLP), were used to determine the existence of diffusion parameters (D, D*, f, and K) within single voxels. Regression algorithms, including linear regression, polynomial regression, ridge, lasso, random forest (RF), elastic-net, and support-vector machines, were used to estimate the value of the diffusion parameters. Performance was evaluated using accuracy (ACC), area under the curve (AUC) tests, and cross-validation root mean square error (RMSECV). Computational timing was also assessed. Results: ETC and MLP were the best classifiers, with 94.1% and 91.7%, respectively, for the ACC test and 98.7% and 96.3% for the AUC test. For parameter estimation, RF algorithm yielded the most accurate results The RMSECV percentages were: 8.39% for D, 3.57% for D*, 4.52% for f, and 3.53% for K. After the training phase, the ML methods demonstrated a substantial decrease in computational time, being approximately 232 times faster than the conventional methods. Conclusions: The findings suggest that ML algorithms can enhance the efficiency of dMRI model analysis and offer new perspectives on the microstructural and functional organization of biological tissues. This paper also discusses the limitations and future directions of ML-based dMRI analysis.

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ABSTRACT Purpose: This study aimed to analyze the association between magnetic resonance imaging apparent diffusion coefficient map value and histopathological differentiation in patients who underwent eye enucleation due to retinoblastomas. Methods: An observational chart review study of patients with retinoblastoma that had histopathology of the lesion and orbit magnetic resonance imaging with apparent diffusion coefficient analysis at Hospital de Clínicas de Porto Alegre between November 2013 and November 2016 was performed. The histopathology was reviewed after enucleation. To analyze the difference in apparent diffusion coefficient values between the two major histopathological prognostic groups, Student's t-test was used for the two groups. All statistical analyses were performed using SPSS version 19.0 for Microsoft Windows (SPSS, Inc., Chicago, IL, USA). Our institutional review board approved this retrospective study without obtaining informed consent. Results: Thirteen children were evaluated, and only eight underwent eye enucleation and were included in the analysis. The others were treated with photocoagulation, embolization, radiotherapy, and chemotherapy and were excluded due to the lack of histopathological results. When compared with histopathology, magnetic resonance imaging demonstrated 100% accuracy in retinoblastoma diagnosis. Optic nerve invasion detection on magnetic resonance imaging showed a 66.6% sensitivity and 80.0% specificity. Positive and negative predictive values were 66.6% and 80.0%, respectively, with an accuracy of 75%. In addition, the mean apparent diffusion coefficient of the eight eyes was 0.615 × 103 mm2/s. The mean apparent diffusion coefficient value of poorly or undifferentiated retinoblastoma and differentiated tumors were 0.520 × 103 mm2/s and 0.774 × 103 mm2/s, respectively. Conclusion: This study revealed that magnetic resonance imaging is useful in the diagnosis of retinoblastoma and detection of optic nerve infiltration, with a sensitivity of 66.6% and specificity of 80%. Our results also showed lower apparent diffusion coefficient values in poorly differentiated retinoblastomas with a mean of 0.520 × 103 mm2/s, whereas in well and moderately differentiated, the mean was 0.774 × 103 mm2/s.

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ABSTRACT Optic neuritis is an important cause of decreased vision due to inflammation of the optic nerve. In view of its complex etiology, a thorough clinical evaluation is essential. Autoimmune optic neuropathy, a rare form of optic neuritis, is associated with progressive, painless, and severe visual loss. Severity depends on the inflammatory and ischemic components of the condition. Autoimmune optic neuropathy is ideally diagnosed with autoimmune disease markers (usually elevated levels of antinuclear antibodies). The treatment is immunosuppression with high doses of corticosteroids. Corticoid dependence is a characteristic of autoimmune optic neuropathy. In this report, we describe a patient with autoimmune optic neuropathy and discuss the importance of laboratory parameters and magnetic resonance imaging findings in the diagnosis of the disease.

RESUMO A Neurite óptica é uma importante causa de diminuição da visão devido à inflamação do nervo óptico. Por apresentar diversas etiologias faz-se necessário ampla investigação. A neuropatia óptica autoimune corresponde a uma doença rara que se manifesta com perda visual aguda, indolor e grave. A gravidade está associada a sua fisiopatogenia com componentes inflamatório e isquêmico. A positividade para marcadores de doenças autoimunes, mais comumente a elevação da titulação de anticorpos antinucleares, são fatores determinantes para o diagnóstico da neuropatia óptica autoimune. O tratamento é feito através de imunossupressão, com necessidade de altas doses de corticoide. Neste relato iremos descrever um paciente com neuropatia óptica autoimune. Discutiremos sobre a importância dos parâmetros laboratoriais e os achados de imagem da ressonância magnética para o diagnóstico.

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Background: Fatigue and cognitive complaints are the most frequent persistent symptoms in patients after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aimed to assess fatigue and neuropsychological performance and investigate changes in the thickness and volume of gray matter (GM) and microstructural abnormalities in the white matter (WM) in a group of patients with mild-to-moderate coronavirus disease 2019 (COVID-19). Methods: We studied 56 COVID-19 patients and 37 matched controls using magnetic resonance imaging (MRI). Cognition was assessed using Montreal Cognitive Assessment and Cambridge Neuropsychological Test Automated Battery, and fatigue was assessed using Chalder Fatigue Scale (CFQ-11). T1-weighted MRI was used to assess GM thickness and volume. Fiber-specific apparent fiber density (FD), free water index, and diffusion tensor imaging data were extracted using diffusion-weighted MRI (d-MRI). d-MRI data were correlated with clinical and cognitive measures using partial correlations and general linear modeling. Results: COVID-19 patients had mild-to-moderate acute illness (95% non-hospitalized). The average period between real-time quantitative reverse transcription polymerase chain reaction-based diagnosis and clinical/MRI assessments was 93.3 (±26.4) days. The COVID-19 group had higher total CFQ-11 scores than the control group (p < 0.001). There were no differences in neuropsychological performance between groups. The COVID-19 group had lower FD in the association, projection, and commissural tracts, but no change in GM. The corona radiata, corticospinal tract, corpus callosum, arcuate fasciculus, cingulate, fornix, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, superior longitudinal fasciculus, and uncinate fasciculus were involved. CFQ-11 scores, performance in reaction time, and visual memory tests correlated with microstructural changes in patients with COVID-19. Conclusions: Quantitative d-MRI detected changes in the WM microstructure of patients recovering from COVID-19. This study suggests a possible brain substrate underlying the symptoms caused by SARS-CoV-2 during medium- to long-term recovery.

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ABSTRACT Bladder cancer (BCa) is one of the most common cancers worldwide and is also considered to be one of the most relapsing and aggressive neoplasms. About 30% of patients will present with muscle invasive disease, which is associated with a higher risk for metastatic disease. The aim of this article is to review the state of art imaging in Radiology, while providing a complete guide to urologists, with case examples, for the rationale of the development of the Vesical Imaging Reporting and Data System (VI-RADS), a scoring system emphasizing a standardized approach to multiparametric Magnetic Resonance Imaging (mpMRI) acquisition, interpretation, and reporting for BCa. Also, we examine relevant external validation studies and the consolidated literature of mpMRI for bladder cancer. In addition, this article discusses some of the potential clinical implications of this scoring system for disease management and follow-up.

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ABSTRACT Background: the diagnosis of Parkinson's disease (PD) can be challenging, especially in the early stages, albeit its updated and validated clinical criteria. Recent developments on neuroimaging in PD, altogether with its consolidated role of excluding secondary and other neurodegenerative causes of parkinsonism, provide more confidence in the diagnosis across the different stages of the disease. This review highlights current knowledge and major recent advances in magnetic resonance and dopamine transporter imaging in aiding PD diagnosis. Objective: This study aims to review current knowledge about the role of magnetic resonance imaging and neuroimaging of the dopamine transporter in diagnosing Parkinson's disease. Methods: We performed a non-systematic literature review through the PubMed database, using the keywords "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". The search was restricted to articles written in English, published between January 2010 and February 2022. Results: The diagnosis of Parkinson's disease remains a clinical diagnosis. However, new neuroimaging biomarkers hold promise for increased diagnostic accuracy, especially in earlier stages of the disease. Conclusion: Future validation of new imaging biomarkers bring the expectation of an increased neuroimaging role in the diagnosis of PD in the following years.

RESUMO Antecedentes: O diagnóstico da doença de Parkinson (DP) pode ser desafiador, principalmente nas fases iniciais da doença, embora tenha critérios clínicos atualizados e validados. Os avanços recentes em neuroimagem na DP, além do seu papel já consolidado de excluir causas secundárias e outras causas neurodegenerativas de parkinsonismo, tem contribuído para uma maior confiabilidade no diagnóstico em diferentes estágios da doença. Nesta revisão, nós destacamos os principais avanços de ressonância magnética e imagem do transportador de dopamina em auxiliar o diagnóstico de DP. Objetivo: realizar uma revisão acerca do conhecimento atual sobre o papel da ressonância magnética e imagem do transportador de dopamina no diagnóstico de doença de Parkinson. Método: Realizamos uma revisão não sistemática da literatura através da base de dados PubMed, utilizando as palavras-chave "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". A busca foi restrita a artigos escritos em inglês, publicados entre janeiro de 2010 e fevereiro de 2022. Resultados: O diagnóstico de doença de Parkinson continua sendo um diagnóstico clínico, contudo, novos biomarcadores de neuroimagem são promissores para o aumento da acurácia diagnóstica, especialmente em fases mais precoces da doença. Conclusão: A validação futura de novos biomarcadores de imagem traz a expectativa de um maior papel da neuroimagem no diagnóstico de doença de Parkinson nos próximos anos.

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Abstract Background: Topographic patterns may correlate with causes of ischemic stroke. Objective: To investigate the association between diffusion-weighted imaging (DWI) and Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Methods: We included 1019 ischemic stroke patients. DWI were classified as: i) negative; ii) DWI single lesion (cortico-subcortical, cortical, subcortical ≥20 mm, or subcortical <20 mm); iii) scattered lesions in one territory (small scattered lesions or confluent with additional lesions); and iv) multiple lesions (multiple unilateral anterior circulation [MAC], multiple posterior circulation [MPC], multiple bilateral anterior circulation [MBAC], and multiple anterior and posterior circulations [MAP]). Results: There was a relationship between DWI patterns and TOAST classification (p<0.001). Large artery atherosclerosis was associated with small, scattered lesions in one vascular territory (Odds Ratio [OR] 4.22, 95% confidence interval [95%CI] 2.61-6.8), MPC (OR 3.52; 95%CI 1.54-8.03), and subcortical lesions <20 mm (OR 3.47; 95%CI 1.76-6.85). Cardioembolic strokes correlated with MAP (OR 4.3; 95%CI 1.64-11.2), cortico-subcortical lesions (OR 3.24; 95%CI 1.9-5.5) and negative DWI (OR 2.46; 95%CI 1.1-5.49). Cryptogenic strokes correlated with negative DWI (OR 4.1; 95%CI 1,84-8.69), cortical strokes (OR 3.3; 95%CI 1.25-8.8), MAP (OR 3.33; 95%CI 1.25-8.81) and subcortical lesion ≥20 mm (OR 2.44; 95%CI 1,04-5.73). Lacunar strokes correlated with subcortical lesions diameter <20 mm (OR 42.9; 95%CI 22.7-81.1) and negative DWI (OR 8.87; 95%CI 4.03-19.5). Finally, MBAC (OR 9.25; 95%CI 1.12-76.2), MAP (OR 5.54; 95%CI 1.94-15.1), and MPC (OR 3.61; 95%CI 1.5-8.7) correlated with stroke of other etiologies. Conclusions: A relationship exists between DWI and stroke subtype.

RESUMEN Antecedentes: Los patrones topográficos pueden correlacionarse con las causas del accidente cerebrovascular isquémico. Objetivo: Investigar la asociación entre imágenes ponderadas por difusión por resonancia nuclear magnética (dRNM) y el ensayo de Org 10172 en la clasificación de tratamiento agudo de accidentes cerebrovasculares (TOAST). Métodos: Fueron incluidos 1.019 pacientes con accidente cerebrovascular isquémico. Las dRNM fueron clasificadas como: i) negativa; ii) dRNM lesión única (cortico-subcortical, cortical, subcortical ≥20 mm, o subcortical <20 mm); iii) lesiones disgregadas un territorio vascular (pequeñas lesiones dispersas o confluentes con lesiones adicionales); y iv) lesiones múltiples (unilaterales de circulación anterior [MAC], de circulación posterior [MPC], bilaterales de circulación anterior [MBAC] y de circulación anterior y posterior [MAP]). Resultados: Existió relación entre los patrones de dRNM y la clasificación TOAST (p<0,001). La aterosclerosis de las arterias grandes se asoció con lesiones pequeñas y disgregadas en un territorio vascular (Odds Ratio [OR] 4,22, intervalo de confianza del 95% [IC95%] 2,61-6,8), MPC (OR 3,52; IC95% 1,54-8,03), y lesiones subcorticales <20 mm (OR 3,47; IC95% 1,76-6,85). Cardioembolias se relacionaron con MAP (OR 4,3; IC95% 1,64-11,2), lesiones cortico-subcorticales (OR 3,24; IC95% 1,9-5,5) y dRNM negativas (OR 2,46; IC95% 1,1-5,49). Los accidentes cerebrovasculares criptogénicos se relacionaron con dRNM negativas (OR 4,1; IC95% 1,84-8,69), accidentes cerebrovasculares corticales (OR 3,3; IC95% 1,25-8,8), MAP (OR 3,33; IC95% 1,25-8,81) y lesiones subcorticales ≥20 mm (OR 2,44; IC95% 1,04-5,73). Los accidentes cerebrovasculares lacunares se correlacionaron con lesiones subcorticales de diámetro <20 mm (OR 42,9; IC95% 22,7-81,1) y dRNM negativas (OR 8,87; IC95% 4,03-19,5). Finalmente, MBAC (OR 9,25; IC95% 1,12-76,2), MAP (OR 5,54; IC95% 1,94-15,1) y MPC (OR 3,61; IC95% 1,5-8,7) se relacionaron con accidentes cerebrovasculares de otras etiologías. Conclusiones: Existe relación entre dRNM y subtipo de accidente cerebrovascular.

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Resumen Introducción: La imagen ponderada en difusión es una técnica de imagen funcional que aporta información complementaria a las secuencias convencionales de resonancia magnética. El coeficiente de difusión aparente (CDA) se valora junto con la secuencia de difusión, calculando el logaritmo negativo de la proporción de intensidades de dos conjuntos de imágenes, lo que permite el análisis cuantitativo de la restricción a la difusión. Objetivo: Determinar si existe una diferencia significativa entre los valores de CDA de las lesiones musculoesqueléticas benignas y malignas, correlacionando los resultados con los hallazgos histológicos. Método: Estudio prospectivo, observacional y descriptivo. Se incluyeron en el trabajo pacientes con sospecha de lesiones tumorales del sistema musculoesquelético de cualquier edad y sexo, sin antecedentes de radioterapia previa o cirugía, evaluados con resonancia magnética y con posterior biopsia o cirugía. Resultados: Se incluyeron 170 pacientes, de los cuales 80 (44 benignos) eran hombres y 90 (43 benignos) eran mujeres. El total fue de 87 lesiones benignas y 83 lesiones malignas, con una media de CDA de 1,44 ± 0,55 × 10−3 mm2/s y de 0,96 ± 0,4 × 10−3 mm2/s, respectivamente, con una diferencia estadísticamente significativa (p < 0,001; 6,335; 168). Conclusiones: Los valores de difusión, y particularmente el CDA, han aportado información adicional en la caracterización de los tumores benignos y malignos, con diferencia significativa, estableciendo valores altos de CDA para los tumores benignos.

Abstract Introduction: Diffusion-weighted imaging is a functional imaging technique that provides complementary information to conventional magnetic resonance imaging sequences. The apparent diffusion coefficient (ADC) is evaluated together with the diffusion sequence, calculating the negative logarithm of the intensity ratio of two image sets, allowing the quantitative analysis of the diffusion. Objective: To determine if there is a statistical significance between the ADC values of benign and malignant musculoskeletal lesions, correlating the results with the histological findings. Method: Prospective, observational and descriptive study. Patients with suspected tumoral lesions of the musculoskeletal system of any age and sex, with no history of prior radiation therapy or surgery, evaluated with resonance with subsequent biopsy or surgery. Results: This study included 170 patients. Male patients were 80 (44 benign), and female patients were 90 (43 benign). The total was 87 benign lesions and 83 malignant lesions, with a mean ADC of 1.44 ± 0.55 × 10−3 mm2/s and 0.96 ± 0.4 × 10−3 mm2/s respectively, with a statistical significance (p < 0.001; 6.335; 168). Conclusions: Diffusion and, in particular, ADC values have provided additional information in the characterization of benign and malignant tumors, with a statistical significance, establishing high ADC values for benign tumors.

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Abstract Introduction: Posterior fossa tumors are common in the pediatric population and require adequate characterization by means of structural magnetic resonance imaging (MRI) and advanced MRI techniques to achieve an appropriate therapeutic approach. Objectives: To determine the usefulness of apparent diffusion coefficient (ADC) values for the differential diagnosis of posterior fossa tumors in the pediatric population treated at a reference hospital in Bogotá D.C., Colombia. Materials and methods: Diagnostic accuracy study carried out in 28 pediatric patients diagnosed with posterior fossa tumor between 2017 and 2019 at the Fundación Hospital de la Misericordia, a quaternary care institution. ADC values were measured and compared with histopathological diagnosis as gold standard, obtaining sensitivity, specificity, and positive and negative predictive values. Differences between medians were determined using the Kruskall-Wallis test. The p value between the quantitative ADC value and the gold standard was calculated using Pearson's chi-squared test, with a significance level of p<0.05. Results: The mean age of the participants was 83.9 months (SD=57 months), and 64.28% of them were boys. Medulloblastoma was the most frequent tumor (39.29%). For the diagnosis of medulloblastoma, an ADC value of 0.6210x10-3mm2/s was established, obtaining a sensitivity and specificity of 81.82% and 76.47%, respectively. For the diagnosis of pilocytic astrocytoma, an ADC of 1.03x10-3mm2/s was determined, with a sensitivity of 66.67% and a specificity of 89.40%. Conclusions: ADC value is useful to classify and differentiate posterior fossa tumors in the Colombian pediatric population, showing an inversely proportional relationship with the tumor grade.

Resumen Introducción. Los tumores de la fosa posterior son frecuentes en población pediátrica y requieren de una adecuada caracterización mediante resonancia magnética (RM) estructural y técnicas avanzadas de RM para lograr un enfoque terapéutico apropiado. Objetivo. Determinar la utilidad de los valores del coeficiente de difusión aparente (ADC cuantitativo) en el diagnóstico diferencial de los tumores de la fosa posterior en población pediátrica de un hospital de referencia en Bogotá D.C., Colombia. Materiales y métodos. Estudio de validez de prueba diagnóstica realizado en 28 pacientes pediátricos diagnosticados con tumor de fosa posterior entre 2017 y 2019 en la Fundación Hospital Pediátrico de la Misericordia, hospital de IV nivel de complejidad. Se midieron los valores del ADC cuantitativo, los cuales fueron comparados con el diagnóstico histopatológico como estándar de oro, obteniendo datos de sensibilidad, especificidad, valores predictivos positivos y negativos. Las diferencias entre medianas fueron determinadas mediante la prueba de Kruskall-Wallis. El valor p entre el valor del ADC cuantitativo y el estándar de oro se calculó con la prueba X2 de Pearson, con un nivel de significancia de p<0.05. Resultados. La edad media fue 83.9 meses (DE=57 meses) y 64.28% fueron niños. El tumor más frecuente fue el meduloblastoma (39.29%). Para el diagnóstico de meduloblastoma se estableció un valor ADC cuantitativo de 0.6210x10-3mm2/s, obteniéndose una sensibilidad y especificidad de 81.82% y 76.47%, respectivamente, y para el diagnóstico de astrocitoma pilocítico, un ADC cuantitativo de 1.03x10-3mm2/s, con una sensibilidad de 66.67% y una especificidad de 89.40%. Conclusiones. El valor del ADC cuantitativo es útil para clasificar y diferenciar los tumores de la fosa posterior en población pediátrica colombiana, mostrando una relación inversamente proporcional con el grado tumoral.

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Bladder cancer (BCa) is one of the most common cancers worldwide and is also considered to be one of the most relapsing and aggressive neoplasms. About 30% of patients will present with muscle invasive disease, which is associated with a higher risk for metastatic disease. The aim of this article is to review the state of art imaging in Radiology, while providing a complete guide to urologists, with case examples, for the rationale of the development of the Vesical Imaging Reporting and Data System (VI-RADS), a scoring system emphasizing a standardized approach to multiparametric Magnetic Resonance Imaging (mpMRI) acquisition, interpretation, and reporting for BCa. Also, we examine relevant external validation studies and the consolidated literature of mpMRI for bladder cancer. In addition, this article discusses some of the potential clinical implications of this scoring system for disease management and follow-up.

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OBJECTIVES: The objective of this investigation was to assess the correlation between the mandible and cervical vertebrae bone marrow apparent diffusion coefficient (ADC), obtained by diffusion-weighted magnetic resonance imaging (DWI), with age; to verify the correlation between ADC values from the mandible and the cervical vertebrae; to describe and assess the differences between ADC values obtained from DWI examinations of distinct mandible areas as well as cervical vertebrae. METHODS: Thirty imaging examinations with DWI for that included the mandible and C1, C2, C3, and C4 vertebrae in the same examination were included. ADC values were collected from 7 distinct areas in the mandible and the cervical vertebrae. Differences between ADC values and non-parametric correlations were performed. RESULTS: A total of 270 regions were assessed. No significant difference was found between ADC values of all areas tested. An inverse correlation was found between C2, C3, and C4 vertebrae ADC values and age. The significant correlation of anatomic area ADC values and age were presented as graphics to verify if the linear trend of ADC values and age are in accordance with the literature CONCLUSIONS: The mandible area that most correlates with the cervical vertebrae, using ADC values, is the posterior trabecular area, below the inferior molars. Also, C2, C3, and C4 vertebrae ADC values inversely correlate with age, which demonstrates the bone qualitative changes in bone composition. ADC values may be useful for the qualitative assessment of bone quality to screen patients at osteoporosis risk.

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ABSTRACT Background: Among patients with acute ischemic stroke with a mismatch between deficit severity and infarct volume, thrombectomy performed within a 6-24 hours time window has efficacy and safety similar to treatment within 6 hours. However, whether magnetic resonance imaging with T2 diffusion-weighted imaging (DWI) is feasible remains to be validated. Objective: To investigate prognosis among stroke patients receiving endovascular treatment (EVT) within 6 hours and 6-24 hours using non-contrasted computed tomography (NCCT) and DWI. Methods: Overall, 209 anterior-circulation ischemic stroke patients with large-vessel occlusion who underwent EVT were divided into ≤ 6 hours and 6-24 hours groups. Patients presenting symptoms within 6 hours were treated if their NIHSS score was ≥ 7 and ASPECTS score was ≥ 5, whereas those with wake-up stroke (WUS) or presenting symptoms 6-24 hours after last seen well (WUS/late-presenting stroke, LPS) were managed if their NIHSS score was ≥ 7 and ASPECTS score was ≥ 5. Results: The percentages of patients undergoing intracranial stenting and intracranial ballooning without stenting significantly differed between two groups (p < 0.001). Grades 0, 1, 2a and 2b recanalization rates did not differ between the 6 hours and 6-24 hours groups (all p > 0.05). Grade 3 recanalization rate in the 6 hours group was significantly lower than in the 6-24 hours group (p = 0.043). The 3-month Rankin Scale score did not significantly differ between the two groups (p = 0.629). Conclusions: EVT is a safe and effective treatment for patients with WUS and LPS selected through NCCT and DWI-based simple imaging.

RESUMO Antecedentes: Entre pacientes com acidente vascular cerebral isquêmico (AVCI) agudo com divergência entre gravidade do déficit e volume do infarto, a trombectomia em 6 a 24 horas tem eficácia e segurança semelhantes ao tratamento em até 6 horas. Entretanto, a viabilidade da imagem ponderada em T2 com difusão (DWI) da ressonância magnética necessita validação. Objetivo: Investigar o prognóstico de pacientes com AVCI que recebem tratamento endovascular (EVT) em até 6 horas e de 6-24 horas usando tomografia computadorizada sem contraste (NCCT) e DWI. Métodos: Duzentos e nove pacientes com AVCI de circulação anterior submetidos a EVT foram divididos em ≤ 6 horas e 6-24 horas. Pacientes com sintomas até 6 horas foram tratados se NIHSS ≥ 7 e ASPECTS ≥ 5; aqueles com AVCI ao despertar (WUS) ou com sintomas entre 6-24 horas da última vez em que foram vistos bem (WUS/AVC de fase tardia, LPS) foram tratados se NIHSS ≥ 7 e ASPECTS ≥ 5. Resultados: As porcentagens de pacientes submetidos a implante de stent intracraniano e angioplastia intracraniana sem stent diferiram entre os dois grupos (p <0,001). As taxas de recanalização 0, 1, 2a e 2b não diferiram entre 6 horas e 6-24 horas (p> 0,05). A taxa de recanalização de grau 3 no grupo 6 horas foi menor do que 6-24 horas (p = 0,043). Pontuação na Escala Rankin (3 meses) não foi diferente (p = 0,629). Conclusões: EVT é um tratamento seguro e eficaz para pacientes com WUS e LPS selecionados por meio de imagens baseadas em NCCT e DWI.

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OBJECTIVE: To establish the diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) in discriminating malignant from non-malignant thoracic lymph nodes. MATERIALS AND METHODS: This was a meta-analysis involving systematic searches of the MEDLINE, EMBASE, and Web of Science databases up through April 2020. Studies reporting thoracic DWI and lymph node evaluation were included. The pooled sensitivity, specificity, diagnostic odds ratio, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated. RESULTS: We evaluated six studies, involving a collective total of 356 mediastinal lymph nodes in 214 patients. Thoracic DWI had a pooled sensitivity and specificity of 92% (95% confidence interval [95% CI]: 71-98%) and 93% (95% CI: 79-98%), respectively. The positive and negative likelihood ratios were 13.2 (95% CI: 4.0-43.8) and 0.09 (95% CI: 0.02-0.36), respectively. The diagnostic odds ratio was 149 (95% CI: 18-1,243), and the AUC was 0.97 (95% CI: 0.95-0.98). CONCLUSION: DWI is a reproducible technique and has demonstrated high accuracy for differentiating between malignant and benign states in thoracic lymph nodes.

OBJETIVO: Uma meta-análise foi realizada para estabelecer o desempenho diagnóstico da ressonância magnética com imagem ponderada em difusão (DWI) na discriminação de linfonodos torácicos malignos de benignos. MATERIAIS E MÉTODOS: MEDLINE, EMBASE e Web of Science foram sistematicamente pesquisados até abril de 2020. Foram incluídos estudos que relatavam o uso de DWI na avaliação de linfonodos torácicos. Sensibilidade, especificidade, razão de chances de diagnóstico, valores preditivos positivos e negativos e área sob a curva (AUC) foram calculados. RESULTADOS: Foram encontrados 356 linfonodos mediastinais de 214 pacientes nos seis estudos incluídos. DWI produziu sensibilidade e especificidade combinadas de 92% (intervalo de confiança 95% [IC 95%]: 71-98%) e 93% (IC 95%: 79-98%), respectivamente. A razão de verossimilhança positiva foi de 13,2 (IC 95%: 4,0-43,8), a razão de verossimilhança negativa foi de 0,09 (IC 95%: 0,02-0,36); A razão de chances de diagnóstico foi de 149 (IC 95%: 18-1.243). A DWI teve uma AUC de 0,97 (IC 95%: 0,95-0,98). CONCLUSÃO: DWI é uma técnica reprodutível que demonstrou alta acurácia na diferenciação de estados malignos e benignos nos linfonodos torácicos.

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Abstract Objective: To establish the diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) in discriminating malignant from non-malignant thoracic lymph nodes. Materials and Methods: This was a meta-analysis involving systematic searches of the MEDLINE, EMBASE, and Web of Science databases up through April 2020. Studies reporting thoracic DWI and lymph node evaluation were included. The pooled sensitivity, specificity, diagnostic odds ratio, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated. Results: We evaluated six studies, involving a collective total of 356 mediastinal lymph nodes in 214 patients. Thoracic DWI had a pooled sensitivity and specificity of 92% (95% confidence interval [95% CI]: 71-98%) and 93% (95% CI: 79-98%), respectively. The positive and negative likelihood ratios were 13.2 (95% CI: 4.0-43.8) and 0.09 (95% CI: 0.02-0.36), respectively. The diagnostic odds ratio was 149 (95% CI: 18-1,243), and the AUC was 0.97 (95% CI: 0.95-0.98). Conclusion: DWI is a reproducible technique and has demonstrated high accuracy for differentiating between malignant and benign states in thoracic lymph nodes.

Resumo Objetivo: Uma meta-análise foi realizada para estabelecer o desempenho diagnóstico da ressonância magnética com imagem ponderada em difusão (DWI) na discriminação de linfonodos torácicos malignos de benignos. Materiais e Métodos: MEDLINE, EMBASE e Web of Science foram sistematicamente pesquisados até abril de 2020. Foram incluídos estudos que relatavam o uso de DWI na avaliação de linfonodos torácicos. Sensibilidade, especificidade, razão de chances de diagnóstico, valores preditivos positivos e negativos e área sob a curva (AUC) foram calculados. Resultados: Foram encontrados 356 linfonodos mediastinais de 214 pacientes nos seis estudos incluídos. DWI produziu sensibilidade e especificidade combinadas de 92% (intervalo de confiança 95% [IC 95%]: 71-98%) e 93% (IC 95%: 79-98%), respectivamente. A razão de verossimilhança positiva foi de 13,2 (IC 95%: 4,0-43,8), a razão de verossimilhança negativa foi de 0,09 (IC 95%: 0,02-0,36); A razão de chances de diagnóstico foi de 149 (IC 95%: 18-1.243). A DWI teve uma AUC de 0,97 (IC 95%: 0,95-0,98). Conclusão: DWI é uma técnica reprodutível que demonstrou alta acurácia na diferenciação de estados malignos e benignos nos linfonodos torácicos.

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OBJECTIVES: Studies performed in the medical area have shown that an indirect diagnosis of bone mineral density (BMD) is feasible by assessing the amount of bone marrow fat with non-ionizing magnetic resonance imaging (MRI). In dentistry, radiographic methods are still the most used for alveolar bone diagnosis. The present literature review aimed at addressing the role of MRI in assessing BMD in medicine and dentistry. METHODS: MEDLINE and EMBASE databases were searched for articles published up to 2019. RESULTS: A total of 428 potentially eligible papers were screened. Of these, 397 were excluded after title, abstract and keyword assessment, yielding 31 papers that potentially met the inclusion criteria. Eleven studies were then excluded because their full texts did not discuss the role of MRI in the indirect diagnosis of BMD. As a result, a total of 20 studies were finally identified as eligible for inclusion in this literature review. Most studies found satisfactory accuracy of MRI for indirectly assessing BMD by quantifying bone mineral fat (BMF). However, only one of these studies was on dentistry. CONCLUSION: Within the limitations of this study, the present findings suggest that MRI is accurate to indirectly estimate bone density by assessing BMF, and could be clinically relevant during dental treatment planning.

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OBJECTIVE: This study sought to evaluate the role of diffusion-weighted imaging (DWI) in differentiation between obstructed and unobstructed bile ducts in patients undergoing magnetic resonance imaging (MRI). METHODS: Eighty-four patients, 40 males and 44 females (mean age: 56.4 ± 15.1 years), undergoing MRI with DWI (0-50-500-700) were evaluated and divided into two groups: 58 with abnormal laboratory tests (obstructed group) and 26 with normal laboratory values (unobstructed group). Laboratory tests were total bilirubin, alkaline phosphatase, and gamma-glutamyltransferase. Median ADC values were calculated and correlated with laboratory tests and degree of bile-duct dilatation (absent, moderate, or severe). The persistence of signal on DWI (b500 and b700) in the biliary tract was evaluated. Bilirubin values were tested for correlation with bile-duct ADC values and persistence of b700 signal. For statistical analysis, Student t test, chi-square test and Wilcoxon-Mann-Whitney test were used. ADC maps were plotted for three levels of the biliary tree, and a receiver operating characteristic (ROC) curve was calculated. RESULTS: In the obstructed group, 15 patients had severe dilatation, 24 had moderate dilatation, and 19 had no appreciable dilatation; 38 patients had persistent signal on b700 images. In the unobstructed group, 23 patients had no dilatation and 3 had moderate dilatation; 4 patients had persistent signal on b700 images. Correlation was found between degree of bile-duct dilatation, bilirubin levels, persistence of b700 signal, and ADC map values. The calculated ADC map cutoff value (353 10-6 mm2/s) was able to differentiate the obstructed and unobstructed groups with 92.3% sensitivity, 81% specificity, and 91.9% accuracy. CONCLUSIONS: DWI is able to distinguish patients with obstructed versus unobstructed bile ducts, regardless of the degree of dilatation, correlating with clinical and laboratory findings.

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ABSTRACT Objective: Evaluation of enlarged mediastinal lymph nodes is crucial for patient management. Malignant lymphoma and sarcoidosis are often difficult to differentiate. Our objective was to determine the diagnostic accuracy of MRI for differentiating between sarcoidosis and malignant lymphoma. Methods: This was a retrospective study involving 47 patients who underwent chest MRI and were diagnosed with one of the diseases between 2017 and 2019. T1, T2, and diffusion-weighted signal intensity were measured. Apparent diffusion coefficients (ADCs) and T2 ratios were calculated. The diagnostic performance of MRI was determined by ROC analysis. Results: Mean T2 ratio was significantly lower in the sarcoidosis group than in the lymphoma group (p = 0.009). The T2-ratio cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 7.1, with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 58.3%, 95.6%, 76.5%, 93.3%, and 68.7%, respectively. The mean ADC was significantly lower in the lymphoma group than in the sarcoidosis group (p = 0.002). The ADC cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 1.205, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 87.5%, 82.6%, 85.1%, 84.0% and 86.3%, respectively. No significant differences were found between the two groups regarding T1 signal intensity, T2 signal intensity, and lymph node diameter. Conclusions: MRI parameters such as ADC, diffusion, and T2 ratio can be useful in the differentiation between sarcoidosis and lymphoma in the evaluation of enlarged lymph nodes.

RESUMO Objetivo: A avaliação de linfonodomegalias mediastinais é crucial para o manejo dos pacientes. O linfoma maligno e a sarcoidose costumam ser difíceis de diferenciar. Nosso objetivo foi determinar a precisão diagnóstica da RMN para diferenciar sarcoidose de linfoma maligno. Métodos: Estudo retrospectivo com 47 pacientes submetidos a RMN de tórax e diagnosticados com uma das doenças entre 2017 e 2019. Foi medida a intensidade do sinal em T1, T2 e difusão. Foram calculados o coeficiente de difusão aparente (ADC, do inglês apparent diffusion coefficient) e a razão T2. O desempenho diagnóstico da RMN foi determinado pela análise da curva ROC. Resultados: A média da razão T2 foi significativamente menor no grupo sarcoidose que no grupo linfoma (p = 0,009). A razão T2 = 7,1 foi o melhor valor de corte para diferenciar linfonodomegalias relacionadas com linfoma daquelas relacionadas com sarcoidose, com sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e precisão de 58,3%, 95,6%, 76,5%, 93,3% e 68,7%, respectivamente. A média do ADC foi significativamente menor no grupo linfoma que no grupo sarcoidose (p = 0,002). O ADC = 1,205 foi o melhor valor de corte para diferenciar linfonodomegalias relacionadas com linfoma daquelas relacionadas com sarcoidose, com sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e precisão de 87,5%, 82,6%, 85,1%, 84,0% e 86,3%, respectivamente. Não houve diferença significativa entre os grupos quanto à intensidade do sinal em T1, intensidade do sinal em T2 e diâmetro dos linfonodos. Conclusões: Parâmetros de RMN como ADC, difusão e razão T2 podem ser úteis na diferenciação entre sarcoidose e linfoma na avaliação de linfonodomegalias.

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Os métodos de imagem são de fundamental importância para o manejo de pacientes com câncer de mama, especialmente no diagnóstico precoce de lesões mamárias não-palpáveis. Os principais exames de imagem utilizados neste contexto são a mamografia (MMG), ultrassonografia (US) e ressonância magnética (RM). Para as lesões classificadas como baixo, médio ou intermediário potencial de malignidade, métodos mais avançados como a RM têm permitido melhores resultados na especificidade para lesões malignas. O objetivo principal deste trabalho foi avaliar a taxa de malignidade e características de imagem das lesões mamárias classificadas na categoria BI-RADS® 4 pela RM, a fim de criar um modelo para subcategorizar estas lesões nas categorias 4A, 4B e 4C, de acordo com o risco de malignidade pelos critérios do Léxico BI-RADS®. Foi realizado um estudo observacional, com a avaliação das lesões mamárias com indicação de biópsia percutânea ou cirúrgica em exames de RM realizados no período de 2016 e 2017 no Departamento de Imagem do A.C.Camargo Cancer Center. Para avaliação da validade diagnóstica o resultado histológico foi considerado comopadrão-ouro e, nos casos negativos para malignidade, foi realizado acompanhamento por pelo menos 2 anos. Foram incluídas 166 pacientes com 199 lesões classificadas com BI-RADS®4. 14 (7,5%) não foram biopsiadas, porém apresentaram estabilidade por pelo menos 2 anos ou não se confirmaram em exames subsequentes, inferindo benignidade. Foram avaliadas por biópsia 185 lesões resultando em 140 (75,6%) lesões benignas e 45 (24,3%) lesões malignas. Apresentaram associação estatisticamente significativa com maior risco de malignidade na análise univariada: composição da mama, realce de fundo do parênquima, morfologia, margens e curva cinética (fases inicial e tardia) das lesões nodulares e na análise multivariada, para os realces nodulares apenas o realce de fundo do parênquima, as margens e a curva cinética (fase inicial) confirmaram significância estatística. Os VPP das classificações subjetiva e objetiva foram, respectivamente, para BI-RADS 4 A 0,0% e 4,3%, 4B 11,8% e 21,4% e 4C 62,2% e 78,9%. Nossos resultados afirmam que a subclassificação pode ajudar a diferenciar as lesões quanto a suspeição de malignidade e demonstrou ser viável, tanto através da avaliação subjetiva dos avaliadores, como através da avaliação objetiva utilizando o modelo desenvolvido a partir do valor preditivo positivo dos diferentes descritores utilizados.

Imaging methods are of fundamental importance for the management of patients with breast cancer, especially in the early diagnosis of non-palpable breast lesions. The main imaging tests used in this context are mammography (MMG), ultrasonography (US) and magnetic resonance imaging (MRI). For lesions classified as low, mild or intermediate malignancy potential, more advanced methods such as MRI have allowed better results in specificity for malignancy. The main objective of this study was to evaluate the malignancy rate and imaging characteristics of breast lesions classified in category BI-RADS® 4 by MRI, in order to create a model to subcategorize these lesions into categories 4A, 4B and 4C, according to the risk of malignancy by the criteria of the BI-RADS® Lexicon. An observational study was carried out, with the evaluation of breast lesions with indication for percutaneous or surgical biopsy in the MRI examination carried out in the period of 2016 and 2017 at the Imaging Department of the ACCamargo Cancer Center. To assess the diagnostic validity, the histological result was considered as the gold standard and in cases negative for malignancy, it was followed for at least 2 years. A total of 166 patients with 199 lesions classified as BI-RADS® 4 were included.14 (7.5%) were not biopsied but were stable for at least 2 years or were not confirmed in subsequent examinations, inferring benignity. 185 lesions were evaluated by biopsy resulting in 140 (75.6%) benign lesions and 45 (24.3%) malignant lesions. They presented a statistically significant association with higher risk of malignancy in the univariate analysis: breast composition, background parenchymal enhancement, morphology, margins and kinetic curve (early and late stages) of nodular lesions and in the multivariate analysis, for nodular enhancements only the enhancement of the parenchyma background, the margins and the kinetic curve (initial phase) confirmed statistical significance. The PPV of the subjective and objective classifications were, respectively, for BI-RADS 4A 0.0% and 4.3%, 4B 11.8% and 21.4% and 4C 62.2% and 78.9%. Our results affirm that the subclassification can help to differentiate the lesions as the suspicion of malignancy and it proved to be feasible, both through the subjective evaluation of the evaluators, as through the objective evaluation using the model developed from the positive predictive value of the different descriptors used.

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OBJECTIVE: To determine whether evaluating the mean apparent diffusion coefficient (ADC) together with capsular contact (CC) adds value in the prediction of microscopic extracapsular extension (ECE) of prostate cancer. MATERIALS AND METHODS: Between January 2012 and December 2016, 383 patients underwent multiparametric magnetic resonance imaging (mpMRI) of the prostate. A total of 67 patients were selected for inclusion. Two radiologists (observers 1 and 2), working independently, performed qualitative and quantitative analyses of ECE, macroscopic ECE, and microscopic ECE. A third radiologist assessed the correlation with the clinical data, and two experienced pathologists reviewed all histopathological findings. RESULTS: Among the 67 patients, mpMRI showed lesions that were confined to the capsule in 44 (66.7%), had microscopic ECE in 12 (17.9%), and had macroscopic ECE in 11 (16.4%). There were no significant differences, in terms of the diagnostic accuracy, as measured by determining the area under the curve (AUC), of CC on T2-weighted images (CCT2), CC on diffusion-weighted imaging (CCDWI), and the mean ADC for the prediction of microscopic ECE, between observer 1 (AUC of 0.728, 0.691, and 0.675, respectively) and observer 2 (AUC of 0.782, 0.821, and 0.799, respectively). Combining the mean ADC with the CCT2 or CCDWI did not improve the diagnostic accuracy for either observer. There was substantial interobserver agreement for the qualitative evaluation of ECE, as demonstrated by the kappa statistic, which was 0.77 (0.66-0.87). The diagnostic accuracy (AUC) of the qualitative assessment for predicting microscopic ECE was 0.745 for observer 1 and 0.804 for observer 2, and the difference was less than significant. In a multivariate analysis, none of clinical or imaging parameters were found to be associated with ECE. CONCLUSION: For the detection of microscopic ECE on mpMRI, CC appears to have good diagnostic accuracy, especially if the observer has considerable experience. Adding the mean ADC to the CCT2 or CCDWI does not seem to provide any significant improvement in that diagnostic accuracy.

OBJETIVO: Avaliar se o coeficiente de difusão aparente (apparent diffusion coefficient - ADC) médio tem valor incremental ao contato capsular (CC) na predição da extensão extracapsular (EEC) do câncer de próstata. MATERIAIS E MÉTODOS: De janeiro de 2012 a dezembro de 2016, 383 pacientes realizaram ressonância magnética multiparamétrica de próstata. Após os critérios de inclusão e exclusão, 67 pacientes foram selecionados para avaliação qualitativa e quantitativa, por dois radiologistas independentes, da EEC, EEC grosseira e EEC microscópica. Um terceiro observador coletou dados clínicos e dois patologistas experientes revisaram os achados histopatológicos. RESULTADOS: Dos 67 pacientes selecionados, 44 apresentaram lesões restritas à cápsula (66,7%), 12 com EEC microscópica (17,9%) e 11 com EEC grosseira (16,4%). Não houve diferença significativa entre a acurácia diagnóstica, medida pela área sob a curva, entre o CC na ponderação T2 (CCT2), CC-difusão e ADC para predição da EEC microscópica para ambos os observadores (0,728, 0,691 e 0,675, respectivamente, para o observador 1, e 0,782, 0,821 e 0,799, respectivamente, para o observador 2). A associação dos valores médios do ADC ao CCT2 e ao CC-difusão não promoveu melhora da acurácia diagnóstica. A concordância interobservador para a avaliação qualitativa da EEC mostrou coeficiente kappa de 0,77 (0,66-0,87), inferindo concordância substancial. A acurácia da avaliação qualitativa para EEC microscópica foi de 0,745 e 0,804 para os observadores 1 e 2, respectivamente, diferença não significativa. Na análise multivariada, nenhum parâmetro clínico ou de imagem foi associado a EEC. CONCLUSÃO: O CC mostrou boa acurácia diagnóstica para a detecção de EEC microscópica, especialmente para o observador mais experiente. A inclusão dos valores médios de ADC não melhorou a acurácia do CC para predição de EEC microscópica.

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Abstract Objective: To determine whether evaluating the mean apparent diffusion coefficient (ADC) together with capsular contact (CC) adds value in the prediction of microscopic extracapsular extension (ECE) of prostate cancer. Materials and Methods: Between January 2012 and December 2016, 383 patients underwent multiparametric magnetic resonance imaging (mpMRI) of the prostate. A total of 67 patients were selected for inclusion. Two radiologists (observers 1 and 2), working independently, performed qualitative and quantitative analyses of ECE, macroscopic ECE, and microscopic ECE. A third radiologist assessed the correlation with the clinical data, and two experienced pathologists reviewed all histopathological findings. Results: Among the 67 patients, mpMRI showed lesions that were confined to the capsule in 44 (66.7%), had microscopic ECE in 12 (17.9%), and had macroscopic ECE in 11 (16.4%). There were no significant differences, in terms of the diagnostic accuracy, as measured by determining the area under the curve (AUC), of CC on T2-weighted images (CCT2), CC on diffusion-weighted imaging (CCDWI), and the mean ADC for the prediction of microscopic ECE, between observer 1 (AUC of 0.728, 0.691, and 0.675, respectively) and observer 2 (AUC of 0.782, 0.821, and 0.799, respectively). Combining the mean ADC with the CCT2 or CCDWI did not improve the diagnostic accuracy for either observer. There was substantial interobserver agreement for the qualitative evaluation of ECE, as demonstrated by the kappa statistic, which was 0.77 (0.66-0.87). The diagnostic accuracy (AUC) of the qualitative assessment for predicting microscopic ECE was 0.745 for observer 1 and 0.804 for observer 2, and the difference was less than significant. In a multivariate analysis, none of clinical or imaging parameters were found to be associated with ECE. Conclusion: For the detection of microscopic ECE on mpMRI, CC appears to have good diagnostic accuracy, especially if the observer has considerable experience. Adding the mean ADC to the CCT2 or CCDWI does not seem to provide any significant improvement in that diagnostic accuracy.

Resumo Objetivo: Avaliar se o coeficiente de difusão aparente (apparent diffusion coefficient - ADC) médio tem valor incremental ao contato capsular (CC) na predição da extensão extracapsular (EEC) do câncer de próstata. Materiais e Métodos: De janeiro de 2012 a dezembro de 2016, 383 pacientes realizaram ressonância magnética multiparamétrica de próstata. Após os critérios de inclusão e exclusão, 67 pacientes foram selecionados para avaliação qualitativa e quantitativa, por dois radiologistas independentes, da EEC, EEC grosseira e EEC microscópica. Um terceiro observador coletou dados clínicos e dois patologistas experientes revisaram os achados histopatológicos. Resultados: Dos 67 pacientes selecionados, 44 apresentaram lesões restritas à cápsula (66,7%), 12 com EEC microscópica (17,9%) e 11 com EEC grosseira (16,4%). Não houve diferença significativa entre a acurácia diagnóstica, medida pela área sob a curva, entre o CC na ponderação T2 (CCT2), CC-difusão e ADC para predição da EEC microscópica para ambos os observadores (0,728, 0,691 e 0,675, respectivamente, para o observador 1, e 0,782, 0,821 e 0,799, respectivamente, para o observador 2). A associação dos valores médios do ADC ao CCT2 e ao CC-difusão não promoveu melhora da acurácia diagnóstica. A concordância interobservador para a avaliação qualitativa da EEC mostrou coeficiente kappa de 0,77 (0,66-0,87), inferindo concordância substancial. A acurácia da avaliação qualitativa para EEC microscópica foi de 0,745 e 0,804 para os observadores 1 e 2, respectivamente, diferença não significativa. Na análise multivariada, nenhum parâmetro clínico ou de imagem foi associado a EEC. Conclusão: O CC mostrou boa acurácia diagnóstica para a detecção de EEC microscópica, especialmente para o observador mais experiente. A inclusão dos valores médios de ADC não melhorou a acurácia do CC para predição de EEC microscópica.