Extra-pituitary midline structural abnormalities associated with ectopic posterior pituitary detected on a new rapid MRI protocol (FAST1.2)

ABSTRACT Objective: Test if the MRI FAST1.2 protocol can detect extra-pituitary midline structural brain abnormalities in patients with ectopic posterior pituitary (EPP), and highlighting their radiological-laboratory correlations. Subjects and methods: Cross-sectional study of patients with EPP and control group. All individuals were submitted to FAST1.2, which combines the FAST1 protocol developed by our group with 3D T2DRIVE imaging. Results: We evaluated 36 individuals with EPP and 78 as control group. Pituitary stalk (PS) was identified in 7/36 patients in EPP group by FAST1, and in 24/36 patients in FAST1.2 (p < 0.001). FAST1 failed to detect PS in one individual in the control group, while the FAST1.2 defined the PS in all individuals. In EPP group, eleven had interhypothalamic adhesion (IHA), three septo-optic dysplasia, and one cerebellar malformation. We didn't observe higher frequency of panhypopituitarism or developmental delay in patients with IHA. In control group, three had pars intermedia cysts, one hydrocephalus, and one hypothalamic hamartoma. Conclusions: FAST1.2 allows confident recognition of midline structural abnormalities, including the pituitary stalk and IHA, thereby making MRI acquisition faster and with no need for contrast administration. IHA could be associated with defects in neuronal migration, as occur in patients with EPP, with no clinical significance.

Neurological imaging findings in hospitalized COVID-19 patients: a retrospective observational study in two Brazilian reference centers / Achados de neuroimagem em pacientes hospitalizados por COVID-19: um estudo retrospectivo e observacional em dois serviços brasileiros de referência

ABSTRACT Background: A variety of neurological manifestations have been attributed to COVID-19. Objective: To investigate the occurrence of neurological symptoms and neuroimaging findings in patients hospitalized in two Brazilian reference centers. Methods: We performed a retrospective cohort study of patients who had laboratory-confirmed COVID-19 presenting in two hospitals in Brazil between March 4 and July 7, 2020, who underwent brain imaging. Results: We recorded 1,359 patients with laboratory-confirmed COVID-19. Brain imaging was performed in 250 (18.4%) patients with neurological symptoms, and nine of them (3.6%) had acute or subacute ischemic stroke neuroimaging findings. Six of the nine patients initially presented with respiratory symptoms while the other three patients presented to the emergency room with acute stroke signs. Conclusions: We described the neuroimaging findings of patients infected with COVID-19 who presented with neurological symptoms in two major hospitals in Brazil. We reinforce the importance of being aware of cerebrovascular complications, both in severe hospitalized patients and in patients who present to the emergency room with acute neurological symptoms, even in the elderly.

RESUMO Introdução: Diversas manifestações neurológicas têm sido atribuídas à COVID-19. Objetivo: Investigar a ocorrência de sintomas neurológicos e achados de neuroimagem em pacientes internados em dois centros de referência brasileiros. Métodos: Estudo retrospectivo que avaliou pacientes internados em dois hospitais no Brasil entre 4 de março e 7 de julho de 2020, com confirmação laboratorial de infecção pelo COVID-19 e que foram submetidos a tomografia computadorizada ou ressonância magnética do crânio em razão de sintomas neurológicos. Resultados: Obtivemos 1.359 pacientes com confirmação laboratorial de infecção pelo COVID-19. Deles, 250 (18,4%) apresentaram sintomas neurológicos e foram submetidos a exames de imagem do crânio e nove (3,6%) demonstraram achados de neuroimagem compatíveis com acidente vascular cerebral (AVC) isquêmico agudo ou subagudo. Em seis dos nove pacientes, observaram-se inicialmente tosse e dispneia graves, enquanto outros três chegaram ao pronto-socorro com sinais de AVC agudo. Conclusões: Foram descritos os achados de neuroimagem em pacientes infectados com COVID-19 em dois grandes centros de referência brasileiros. Reforçamos a importância de estar atento aos quadros neurológicos, especialmente de AVC, tanto em pacientes graves hospitalizados quanto em pacientes que chegam ao pronto-socorro com sintomas neurológicos agudos, mesmo em idosos.

Current uses of intracranial vessel wall imaging for clinical practice: a high-resolution MR technique recently available / Usos atuais do estudo de parede vascular intracraniana na prática clínica: uma técnica de RM de alta resolução recentemente disponível

ABSTRACT Intracranial vessel wall imaging plays an increasing role in diagnosing intracranial vascular diseases. With the growing demand and subsequent increased use of this technique in clinical practice, radiologists and neurologists should be aware of the choices in imaging parameters and how they affect image quality, clinical indications, methods of assessment, and limitations in the interpretation of these images. Due to the improvement of the MRI techniques, the possibility of accurate and direct evaluation of the abnormalities in the arterial vascular wall (vessel wall imaging) has evolved, adding substantial data to diagnosis when compared to the indirect evaluation based on conventional flow analyses. Herein, the authors proposed a comprehensive approach of this technique reinforcing appropriated clinical settings to better use intracranial vessel wall imaging.

RESUMO O estudo angiográfico intracraniano não invasivo está sendo amplamente utilizado no diagnóstico de doenças vasculares intracranianas. Com a crescente demanda e o aumento subsequente do uso dessa técnica na prática clínica, radiologistas e neurologistas devem estar cientes das opções nos parâmetros de imagem e como estes afetam a qualidade da imagem, as indicações clínicas, os métodos de avaliação e as limitações na interpretação dessas imagens. Devido ao aprimoramento das técnicas de imagem por RM, a possibilidade de avaliação precisa e direta das anormalidades na parede vascular arterial (vessel wall imaging) evoluiu, agregando dados substanciais ao diagnóstico quando comparados à avaliação indireta baseada em análises de fluxo convencionais. Neste artigo, os autores discorrem sobre a avaliação e interpretação dos achados de imagem desta nova técnica e suas aplicações clínicas.

Improving acute demyelinating lesion detection: which T1-weighted magnetic resonance acquisition is more sensitive to gadolinium enhancement? / Aumento da detecção das placas desmielinizantes agudas: qual aquisição de ressonância magnética ponderada em T1 é a mais sensível em demonstrar impregnação pelo gadolínio?

ABSTRACT Because of the need for a standardized and accurate method for detecting multiple sclerosis (MS) inflammatory activity, different magnetic resonance (MR) acquisitions should be compared in order to choose the most sensitive sequence for clinical routine. Objective To compare the sensitivity of a T1-weighted image to a single dose of gadolinium (Gd) administration both with and without magnetization transfer to detect contrast enhancement in active demyelinating focal lesions. Methods A sample of relapsing-remitting MS patients were prospectively examined separately by two neuroradiologists using a 1.5 Tesla scanner. The outcome parameters were focused on Gd-enhancement detection attributed to acute demyelination. All MR examinations with at least one Gd-enhancing lesion were considered positive (MR+) and each lesion was analyzed according to its size and contrast ratio. Results Thirty-six MR examinations were analyzed with a high inter-observer agreement for MR+ detection (k coefficient > 0.8), which was excellent for the number of Gd-enhancing lesions (0.91 T1 spin-echo (SE), 0.88 T1 magnetization transfer contrast (MTC) sequence and 0.99 magnetization-prepared rapid acquisition with gradient-echo (MPRAGE). Significantly more MR+ were reported on the T1 MTC scans, followed by the T1 SE, and MPRAGE scans. Confidently, the T1 MTC sequence demonstrated higher accuracy in the detection of Gd-enhancing lesions, followed by the T1 SE and MPRAGE sequences. Further comparisons showed that there was a statistically significant increase in the contrast ratio and area of Gd-enhancement on the T1 MTC images when compared with both the SE and MPRAGE images. Conclusion Single-dose Gd T1 MTC sequence was confirmed to be the most sensitive acquisition for predicting inflammatory active lesions using a 1.5 T magnet in this sample of MS patients.

RESUMO No que se refere à necessidade de um método preciso e padronizado para a detecção de atividade inflamatória em esclerose múltipla (EM), diferentes aquisições de RM devem ser comparadas com objetivo de escolher a sequência mais sensível para a rotina clínica. Objetivo Comparar a sensibilidade das sequências ponderadas em T1 após a administração endovenosa de uma única dose de gadolínio, com e sem a adição da transferência de magnetização, para detectar a impregnação das lesões desmielinizantes focais agudas. Métodos Uma amostra de pacientes com EM-RR foi prospectivamente avaliada separadamente por dois neurorradiologistas em um equipamento de RM de 1,5 Tesla. Os parâmetros de desfecho foram direcionados para a avaliação da detecção de impregnação pelo Gd atribuída à desmielinização aguda. Todos os exames de RM que demonstraram ao menos uma lesão com impregnação pelo Gd foram considerados positivos (RM+) e cada lesão foi analisada de acordo com suas dimensões e contraste. Resultados Trinta e seis exames de RM foram analisados. Os avaliadores demonstraram elevada concordância para a detecção de RM+ (coeficiente> 0,8), sendo excelente quanto ao número de lesões com impregnação pelo Gd (0,91 SE, 0,88 T1 MTC e 0,99 MPRAGE). A sequência T1 MTC apresentou número significativamente maior de RM+, seguida pelas sequências T1 SE e MPRAGE. De forma análoga, a sequência T1 MTC demonstrou maior acurácia na detecção de lesões com impregnação pelo Gd, seguida pelas sequências T1 SE e MPRAGE. As demais comparações demonstraram aumento estatisticamente significativo na relação de contraste e na área de impregnação pelo Gd nas imagens T1 MTC quando comparadas às imagens SE e MPRAGE. Conclusão A sequência T1 MTC com uma única dose de Gd confirmou ser a sequência mais sensível em demonstrar lesões inflamatórias agudas em equipamento de 1,5 T nessa coorte de pacientes com EM.

Modern techniques of magnetic resonance in the evaluation of primary central nervous system lymphoma: contributions to the diagnosis and differential diagnosis

Abstract In addition to findings from conventional magnetic resonance imaging, modern magnetic resonance imaging techniques have provided important information about tumor metabolism, in vivo metabolite formation, water molecule diffusion, microvascular density, and blood-brain barrier permeability, all of which have improved the in vivo diagnostic accuracy of this method in the evaluation of primary central nervous system lymphoma. These nonconventional magnetic resonance techniques are useful in the clinical practice because they enhance conventional magnetic resonance imaging by reinforcing the possibility of a diagnosis and by allowing the early detection of disease recurrence. This report is a review of the most relevant contributions of nonconventional magnetic resonance techniques to the imaging diagnosis of primary central nervous system lymphoma, the differential diagnosis of this disease, and the prognosis of patients. This paper aims to describe a wide range of presentations of primary central nervous system lymphoma, their appearance in imaging, and the differential diagnoses of this disease.

Dementia in motor neuron disease: reviewing the role of MRI in diagnosis / Demência em doença do neurônio motor: revisão do papel da RM no diagnóstico

ABSTRACT The superimposed clinical features of motor neuron disease (MND) and frontotemporal dementia (FTD) comprise a distinct, yet not fully understood, neurological overlap syndrome whose clinicopathological basis has recently been reviewed. Here, we present a review of the clinical, pathological and genetic basis of MND-FTD and the role of MRI in its diagnosis. In doing so, we discuss current techniques that depict the involvement of the selective corticospinal tract (CST) and temporal lobe in MND-FTD.

RESUMO As características clínicas sobreposta da doença do neurônio motor (DNM) e demência frontotemporal (DFT) compreendem um distinto ainda não totalmente compreendido, base neurológica síndrome de sobreposição clínico-patológico foi recentemente revisto. Aqui, apresentamos uma revisão das bases clínicas, patológicas e genética de DNM-DFT e o papel da ressonância magnética no diagnóstico STI. Ao fazê-lo, discutimos as técnicas atuais que retratam o envolvimento do trato corticoespinhal seletiva (TCS) e lobo temporal em DNM-DFT.

Multidetector computed tomography angiography in clinically suspected hyperacute ischemic stroke in the anterior circulation: an etiological workup in a cohort of Brazilian patients / Angiotomografia computadorizada multidetectores na avaliação da suspeita clínica de acidente vascular encefálico isquêmico hiperagudo da circulação anterior: determinação etiológica precoce em um grupo de pacientes brasileiros

Objective The potential of computed tomography angiography (CTA) was assessed for early determination of stroke subtypes in a Brazilian cohort of patients with stroke. Method From July 2011 to July 2013, we selected patients with suspected hyperacute stroke (< 6 hours). Intracranial and cervical arteries were scrutinized on CTA and their imaging features were correlated with concurrent subtype of stroke. Results Stroke was documented in 50/106 selected patients (47.2%) based on both clinical grounds and imaging follow-up (stroke group), with statistically significant arterial stenosis and vulnerable plaques on CTA. Intracranial large artery disease was demonstrated in 34% of patients in the stroke group. Partial territorial infarct prevailed (86%) while artery-to-artery embolization was the most common stroke mechanism (52%). Conclusion Multidetector CTA was useful for the etiologic work-up of hyperacute ischemic stroke and facilitated the knowledge about the topographic pattern of brain infarct in accordance with its causative mechanism. .

Objetivo Avaliar o potencial da angiotomografia computadorizada multidetectores (ATCM) na determinação etiológica precoce do acidente vascular encefálico (AVE) e correlacionar o mecanismo causal com o padrão de infarto. Método De Julho de 2011 a Julho de 2013, foram selecionados os pacientes com suspeita clínica de AVE hiperagudo. Os achados da ATCM dos vasos intracranianos e cervicais foram correlacionados com a etiologia final do evento. Resultados AVE foi confirmado em 50/106 pacientes (47,2%). Estes apresentaram alterações angiográficas estatisticamente mais relevantes. Aterosclerose dos grandes vasos intracranianos esteve presente em 34% destes pacientes. O padrão radiológico topográfico de infarto mais comum foi o infarto territorial parcial (86%). A embolização arterio-arterial foi o mecanismo mais prevalente (52%). Conclusão A utilização da ATCM traz benefícios na detecção etiológica precoce dos pacientes com suspeita de AVE hiperagudo, além de possibilitar o entendimento do padrão radiológico topográfico de acordo com o mecanismo causal do evento isquêmico. .

Active extravasation of contrast within the hemorrhage (spot sign): a multidetector computed tomography finding that predicts growth and a worse prognosis in non-traumatic intracerebral hemorrhage / Extravasamento ativo de contraste no interior da hemorragia (spot sign): um achado de TCMD que prediz crescimento e pior prognostico nas hemorragias intraparenquimatosas cerebrais nao traumaticas

Intracerebral hemorrhage (ICH) causes high rates of disability and neurological sequelae Objective To evaluate spot signs as predictors of expansion and worse prognosis in non-traumatic ICH in a Brazilian cohort. Method We used multidetector computed tomography angiography to study 65 consecutive patients (40 men, 61.5%), with ages varying from 33 to 89 years (median age 55 years). Clinical and imaging findings were correlated with the findings based on the initial imaging. Results Of the individuals who presented a spot sign, 73.7% died (in-hospital mortality), whereas in the absence of a spot sign the mortality rate was 43.0%. Although expansion of ICH was detected in 75% of the patients with a spot sign, expansion was observed in only 9.0% of the patients who did not present a spot sign. Conclusions The spot sign strongly predicted expansion in non-traumatic ICH and an increased risk of in-hospital mortality. .

A hemorragia intraparenquimatosa cerebral (HIC) apresenta altas taxas de incapacidade e sequela neurológica. Objetivo Avaliar a presença de spot sign como preditor de expansão e pior prognóstico no follow-up de HIC não-traumática em brasileiros. Método Usamos a ângio-tomografia para estudar prospectivamente 65 pacientes consecutivos (40 homens 61,5%), com idades variando de 33 a 89 anos (mediana 55 anos). Evolução clínica e achados de imagem foram correlacionados com a interpretação dos achados do exame inicial. Resultados 73,7% dos indivíduos com spot sign no estudo tomográfico inicial evoluíram para óbito e, na sua ausência, a taxa de mortalidade foi 43,0%. Enquanto a expansão da HIC foi detectada em 75% dos pacientes com spot sign, ela foi notada em 9% daqueles sem este sinal. Conclusão O spot sign mostrou-se forte preditor de expansão da HIC não traumática e representa maior risco de morte hospitalar nesta coorte de pacientes. .