Internal carotid artery bulb width: a novel potential parameter for the prediction of cerebral vascular diseases.

OBJECTIVE: To investigate the relationship between the width of the internal carotid artery (ICA) bulb and cerebral vascular diseases including stroke and intracranial aneurysms. MATERIAL AND METHODS: In total 300 patients who had supra-aortic computed tomography angiography (CTA) were enrolled in this study from 2015 to 2021. The study groups consisted of 100 ischemic stroke patients, 100 patients with intracranial aneurysms, and 100 control subjects. The intracranial aneurysm patient group was divided into two subgroups according to the presence of subarachnoid hemorrhage (SAH). The largest diameters of the ICA C1 (cervical) and C2 (petrous) segments in all individuals were measured bilaterally on CTA images. The ICA diameter ratios of the cases were measured using the formula C1-C2C1. The relationship between the age and ICA vessel analysis was evaluated as well. RESULTS: The mean ICA bulb width values in the ischemic stroke patient group and the intracranial aneurysm patient group were significantly higher than the control group (p < 0.001). The ICA C1 and C2 segment diameter values and ICA diameter ratio were smaller in the intracranial aneurysm patients with SAH than those who had not (p = 0.7). There was a statistically significant but weak relationship between the age and ICA diameter ratios in all study groups (R-squared value of 0.26, p = 0.03). CONCLUSION: ICA bulb width is a parameter that can be easily evaluated with neuroimaging modalities and is a successful method that may be used for predicting the risk of ischemic stroke or the presence of an intracranial aneurysm.

Lesiones inflamatorias del troncoencéfalo: claves diagnósticas en RM / Inflammatory lesions of the brainstem: Keys for the diagnosis by MRI

Objetivo: Describir los hallazgos en resonancia magnética (RM) de las principales enfermedades inflamatorias e inmunomediadas que afectan al troncoencéfalo. Conclusión: El diagnóstico diferencial de las lesiones inflamatorias localizadas en el troncoencéfalo es complicado debido al amplio espectro de enfermedades autoinmunes, infecciosas y síndromes paraneoplásicos que pueden causarlas. Conocer estas entidades, sus características clínicas y sus manifestaciones en RM, sobre todo en cuanto a número, morfología, extensión y apariencia en las diferentes secuencias, es útil a la hora de orientar el diagnóstico radiológico.(AU)

Objective: To describe the magnetic resonance imaging (MRI) findings for the most common inflammatory and immune-mediated diseases that involve the brainstem. Conclusion: Inflammatory lesions involving the brainstem are associated with a wide range of autoimmune, infectious, and paraneoplastic syndromes, making the differential diagnosis complex. Being familiar with these entities, their clinical characteristics, and their manifestations on MRI, particularly the number of lesions, their shape and extension, and their appearance in different sequences, is useful for orienting the radiological diagnosis.(AU)

Inflammatory lesions of the brainstem: Keys for the diagnosis by MRI.

OBJECTIVE: To describe the magnetic resonance imaging (MRI) findings for the most common inflammatory and immune-mediated diseases that involve the brainstem. CONCLUSION: Inflammatory lesions involving the brainstem are associated with a wide range of autoimmune, infectious, and paraneoplastic syndromes, making the differential diagnosis complex. Being familiar with these entities, their clinical characteristics, and their manifestations on MRI, especially the number of lesions, their shape and extension, and their appearance in different sequences, is useful for orienting the radiological diagnosis.

La enfermedad de Lhermitte-Duclos (ELD): Reporte del primer caso registrado en Paraguay con correlación radiológica-patológica

La enfermedad de Lhermitte-Duclos, o gangliocitoma displásico cerebeloso, es una rara entidad que se manifiesta como un proceso expansivo de crecimiento lento en la fosa posterior, específicamente en el cerebelo, con una patogenia no muy bien comprendida, que puede estar relacionada con anomalías congénitas y mutaciones del gen PTEN (fosfatasa y homólogo de tensina) sobre todo en la forma de presentación adulta. Los casos documentados de esta enfermedad son escasos, con alrededor de 230 registros en la literatura médica y una prevalencia menor a 1 por cada millón de personas. Presentamos el primer caso en Paraguay de Enfermedad de Lhermitte-Duclos en un paciente masculino de 44 años, sin antecedentes médicos o familiares relevantes, que fue intervenido quirúrgicamente por proceso expansivo de fosa posterior, con hallazgos característicos en la resonancia magnética, que permitió sospechar preoperatoriamente de la enfermedad, con diagnóstico diferencial de meduloblastoma, debido a restricciones observadas en la secuencia de Difusión. La resección fue completa con adecuada evolución y sin recaídas del proceso.

Lhermitte-Duclos disease, or cerebellar dysplastic gangliocytoma, is a rare entity that manifests as a slow-growing expansive process in the posterior fossa, specifically in the cerebellum, with a pathogenesis that is not well understood, which may be related to congenital anomalies and PTEN gene mutations (phosphatase and tensin homologue), especially in the form of adult presentation. Documented cases of this disease are scarce, with around 230 records in the medical literature and a prevalence of less than 1 per million people. We present the first case in Paraguay of dysplastic gangliocytoma or Lhermitte-Duclos disease in a 44-year-old male patient, with no relevant medical or family history, who underwent surgery due to an expansive process in the posterior fossa, with characteristic findings on magnetic resonance, which allowed preoperative suspicion of the disease, with differential diagnosis of medulloblastoma, due to restrictions observed in the Diffusion sequence. The resection was complete with adequate evolution and without relapses of the process. Keywords: Lhermitte- Duclos; Gangliocytoma; dysplastic; cerebellar; neuroradiology.

Recomendaciones para la coordinación de los servicios de Neurología y Neurorradiología en la atención a pacientes con esclerosis múltiple / Recommendations for the coordination of Neurology and Neuroradiology Departments in the management of patients with multiple sclerosis

Introducción: El uso de la resonancia magnética (RM) está ampliamente extendido en el diagnóstico y el seguimiento de los pacientes con esclerosis múltiple (EM). La coordinación entre los servicios de Neurología y Neurorradiología es clave para la realización e interpretación de estudios radiológicos de la manera más eficaz posible. Sin embargo, esta coordinación es susceptible de mejoras en una gran parte de los hospitales nacionales. Métodos: Un panel de 17 neurólogos y neurorradiólogos de 8 hospitales españoles, presencialmente y a través de comunicación online, consensuaron una guía de buenas prácticas en la coordinación en EM. La guía se estableció en 4 fases: 1) definición del alcance de la guía y metodología del estudio; 2) revisión bibliográfica sobre buenas prácticas o recomendaciones en el uso de la RM en EM; 3) discusión y búsqueda de consenso entre los expertos; y 4) formalización y validación de los contenidos para elaborar el documento de consenso. Resultados: Se consensuaron un total de 9 recomendaciones dirigidas a la mejora de la coordinación entre los servicios de Neurología y Neurorradiología, que se pueden resumir en: 1) estandarizar las solicitudes de RM, informes y planificación; 2) crear protocolos compartidos para los estudios de RM; 3) establecer comités multidisciplinares y sesiones de coordinación, y 4) generar canales de comunicación formales entre los profesionales de ambos departamentos. Conclusiones: Se espera que las recomendaciones consensuadas sirvan de guía para optimizar la coordinación entre neurólogos y neurorradiólogos y que repercutan en la mejora del diagnóstico y seguimiento de los pacientes con EM.(AU)

Introduction: Magnetic resonance imaging (MRI) is widely used for the diagnosis and follow-up of patients with multiple sclerosis (MS). Coordination between Neurology and Neuroradiology departments is crucial for performing and interpreting radiological studies as efficiently and as accurately as possible. However, improvements can be made in the communication between these departments in many Spanish hospitals. Methods: A panel of 17 neurologists and neuroradiologists from 8 Spanish hospitals held in-person and online meetings to draft a series of good practice guidelines for the coordinated management of MS. The drafting process included 4 phases: 1) establishing the scope of the guidelines and the methodology of the study; 2) literature review on good practices or recommendations on the use of MRI in MS; 3) discussion and consensus between experts; and 4) validation of the contents. Results: The expert panel agreed a total of 9 recommendations for improving coordination between neurology and neuroradiology departments. The recommendations revolve around 4 main pillars: 1) standardising the process for requesting and scheduling MRI studies and reports; 2) designing common protocols for MRI studies; 3) establishing multidisciplinary committees and coordination meetings; and 4) creating formal communication channels between both departments. Conclusions: These consensus recommendations are intended to optimise coordination between neurologists and neuroradiologists, with the ultimate goal of improving the diagnosis and follow-up of patients with MS.(AU)

Recommendations for the coordination of Neurology and Neuroradiology Departments in the management of patients with multiple sclerosis.

INTRODUCTION: Magnetic resonance imaging (MRI) is widely used for the diagnosis and follow-up of patients with multiple sclerosis (MS). Coordination between neurology and neuroradiology departments is crucial for performing and interpreting radiological studies as efficiently and as accurately as possible. However, improvements can be made in the communication between these departments in many Spanish hospitals. METHODS: A panel of 17 neurologists and neuroradiologists from 8 Spanish hospitals held in-person and online meetings to draft a series of good practice guidelines for the coordinated management of MS. The drafting process included 4 phases: 1) establishing the scope of the guidelines and the methodology of the study; 2) literature review on good practices or recommendations on the use of MRI in MS; 3) discussion and consensus between experts; and 4) validation of the contents. RESULTS: The expert panel agreed a total of 9 recommendations for improving coordination between neurology and neuroradiology departments. The recommendations revolve around 4 main pillars: 1) standardising the process for requesting and scheduling MRI studies and reports; 2) designing common protocols for MRI studies; 3) establishing multidisciplinary committees and coordination meetings; and 4) creating formal communication channels between both departments. CONCLUSIONS: These consensus recommendations are intended to optimise coordination between neurologists and neuroradiologists, with the ultimate goal of improving the diagnosis and follow-up of patients with MS.

Cronotaraxis como síntoma guía de un infarto talámico medial / Chronotaraxis as a harbinger of medial thalamic infarction

La cronotaraxis es una afectación de la percepción de la secuencia temporal. Esta alteración de la temporalidad se ha descrito asociada de forma característica a la afectación talámica, concretamente al núcleo dorsomediano. Casos clínicos. Presentamos los casos clínicos de dos pacientes con ictus isquémicos agudos de localización en dicho territorio, con una clínica basada en este síntoma y cuyo reconocimiento resultó esencial en el abordaje terapéutico. Tanto en el primero como en el segundo caso se describe cómo la percepción de la temporalidad fue esencial para el diagnóstico de la patología isquémica de ambos pacientes. Discusión. El conocimiento y la divulgación de esta asociación pueden resultar fundamentales en el manejo de los pacientes con alteraciones talámicas. Esto se debe a la posibilidad que surge de influir y modificar el abordaje inicial, puesto que el reconocimiento de un síntoma específico, como es la cronotaraxis, puede evitar la extensión del daño talámico, y prevenir de esta manera las secuelas, sobre todo cognitivas, que ocasiona a largo plazo.(AU)

Introduction: Chronotaraxis is an impairment of the perception of the sequencing of time. This alteration of temporality has been described as being characteristically associated with thalamic involvement, specifically in the dorsomedial nucleus. Case reports: We report the clinical cases of two patients with acute ischaemic strokes located in said territory, with a clinical presentation based on this symptom and the recognition of which was essential in the therapeutic approach. In the first and second cases, it is described how the perception of temporality was essential for the diagnosis of the ischaemic condition in both patients. Discussion: Awareness and dissemination of this association may be vital in the management of patients with thalamic disorders. This is due to the possibility of influencing and modifying the initial approach, since the recognition of a specific symptom, such as chronotaraxis, can prevent the spread of thalamic damage, in addition to the long-term sequelae that it causes, especially those of a cognitive nature.(AU)

Recommendations for the diagnosis and radiological follow-up of pituitary neuroendocrine tumours.

Pituitary neuroendocrine tumours (PitNETs) constitute a heterogeneous group of tumours with a gradually increasing incidence, partly accounted for by more sensitive imaging techniques and more extensive experience in neuroradiology in this regard. Although most PitNETs are indolent, some exhibit aggressive behaviour, and recurrence may be seen after surgical removal. The changes introduced in the WHO classification in 2017 and terminological debates in relation to neuroendocrine tumours warrant an update of the guidelines for the diagnosis, preoperative and postoperative management, and follow-up of response to treatment of PitNETs. This multidisciplinary document, an initiative of the Neuroendocrinology area of the Sociedad Española de Endocrinología y Nutrición [Spanish Society of Endocrinology and Nutrition] (SEEN), focuses on neuroimaging studies for the diagnosis, prognosis and follow-up of PitNETs. The basic requirements and elements that should be covered by magnetic resonance imaging are described, and a minimum radiology report to aid clinicians in treatment decision-making is proposed. This work supplements the consensus between the Neuroendocrinology area of the SEEN and the Sociedad Española de Anatomía Patológica [Spanish Society of Pathology] (SEAP) for the pathological study of PitNETs.

Recommendations for the coordination of Neurology and Neuroradiology Departments in the management of patients with multiple sclerosis. / Recomendaciones para la coordinación de los servicios de Neurología y Neurorradiología en la atención a pacientes con esclerosis múltiple.

INTRODUCTION: Magnetic resonance imaging (MRI) is widely used for the diagnosis and follow-up of patients with multiple sclerosis (MS). Coordination between Neurology and Neuroradiology departments is crucial for performing and interpreting radiological studies as efficiently and as accurately as possible. However, improvements can be made in the communication between these departments in many Spanish hospitals. METHODS: A panel of 17 neurologists and neuroradiologists from 8 Spanish hospitals held in-person and online meetings to draft a series of good practice guidelines for the coordinated management of MS. The drafting process included 4 phases: 1) establishing the scope of the guidelines and the methodology of the study; 2) literature review on good practices or recommendations on the use of MRI in MS; 3) discussion and consensus between experts; and 4) validation of the contents. RESULTS: The expert panel agreed a total of 9 recommendations for improving coordination between neurology and neuroradiology departments. The recommendations revolve around 4 main pillars: 1) standardising the process for requesting and scheduling MRI studies and reports; 2) designing common protocols for MRI studies; 3) establishing multidisciplinary committees and coordination meetings; and 4) creating formal communication channels between both departments. CONCLUSIONS: These consensus recommendations are intended to optimise coordination between neurologists and neuroradiologists, with the ultimate goal of improving the diagnosis and follow-up of patients with MS.

Effects of lumbar myelography on subarachnoid pressure and cardiorespiratory parameters in healthy sheep

ABSTRACT: The purpose of this study was to evaluate the effects of lumbar myelography on subarachnoid pressure, cardiorespiratory parameters and pressure-volume index in sheep. Eight sheep were evaluated. The animals were submitted to puncture of the cisterna magna for monitoring of subarachnoid pressure (SaP). Lumbar myelography was performed through applying Iohexol (0.4mL/kg). ToC, PAS, PAD, MAP, InspISO, FeISO, SaP and CPP were recorded immediately after anesthetic stabilization (M0), during lumbar puncture (M1), and two, four and six minutes after contrast application (M2, M3 and M4, respectively). Blood pressure initially increased, then decreased, returning to basal level, similarly observed for InspISo and FeISo. The SaP rose initially thereafter remaining stable. Despite of the effect on subarachnoid pressure, lumbar myelography can be considered safe in sheep.

RESUMO: O objetivo foi avaliar os efeitos da mielografia lombar na pressão subaracnóidea, parâmetros cardiorrespiratórios e índice pressão-volume em ovinos. Oito ovelhas foram avaliadas. Os animais foram submetidos à punção da cisterna magna para monitoramento da pressão subaracnoidea (SaP). A mielografia lombar foi realizada com a aplicação de Iohexol (0,4mL/kg). Os momentos estudados foram: imediatamente após a estabilização anestésica (M0), durante a punção lombar (M1), dois, quatro e seis minutos após a aplicação do contraste (M2, M3 e M4, respectivamente), para avaliar as seguintes variáveis: ToC, PAS, PAD, MAP, InspISO, FeISO, Sap e CPP. A pressão arterial aumentou inicialmente, depois diminuiu, retornando aos valores iniciais, padrão também observado para o InspISo e o FeISo. O SaP subiu inicialmente, posteriormente, permanecendo estável. A mielografia lombar, apesar de influenciar a pressão subaracnoidea, pode ser considerada segura em ovinos.

Effects of lumbar myelography on subarachnoid pressure and cardiorespiratory parameters in healthy sheep / Efeitos da mielografia lombar na pressão subaracnoidea e nos parâmetros cardiorrespiratórios em ovelhas saudáveis

The purpose of this study was to evaluate the effects of lumbar myelography on subarachnoid pressure, cardiorespiratory parameters and pressure-volume index in sheep. Eight sheep were evaluated. The animals were submitted to puncture of the cisterna magna for monitoring of subarachnoid pressure (SaP). Lumbar myelography was performed through applying Iohexol (0.4mL/kg). ToC, PAS, PAD, MAP, InspISO, FeISO, SaP and CPP were recorded immediately after anesthetic stabilization (M0), during lumbar puncture (M1), and two, four and six minutes after contrast application (M2, M3 and M4, respectively). Blood pressure initially increased, then decreased, returning to basal level, similarly observed for InspISo and FeISo. The SaP rose initially thereafter remaining stable. Despite of the effect on subarachnoid pressure, lumbar myelography can be considered safe in sheep.(AU)

O objetivo foi avaliar os efeitos da mielografia lombar na pressão subaracnóidea, parâmetros cardiorrespiratórios e índice pressão-volume em ovinos. Oito ovelhas foram avaliadas. Os animais foram submetidos à punção da cisterna magna para monitoramento da pressão subaracnoidea (SaP). A mielografia lombar foi realizada com a aplicação de Iohexol (0,4mL/kg). Os momentos estudados foram: imediatamente após a estabilização anestésica (M0), durante a punção lombar (M1), dois, quatro e seis minutos após a aplicação do contraste (M2, M3 e M4, respectivamente), para avaliar as seguintes variáveis: ToC, PAS, PAD, MAP, InspISO, FeISO, Sap e CPP. A pressão arterial aumentou inicialmente, depois diminuiu, retornando aos valores iniciais, padrão também observado para o InspISo e o FeISo. O SaP subiu inicialmente, posteriormente, permanecendo estável. A mielografia lombar, apesar de influenciar a pressão subaracnoidea, pode ser considerada segura em ovinos.(AU)

A symptomatic large subependymoma with neuroradiological features mimicking a high-grade glioma: A case report.

A subependymoma is a benign primary brain tumor classified as a World Health Organization grade I tumor; it is asymptomatic in most cases. We present the case of a 66-year-old Japanese man with a complaint of recurrent vomiting that led to the discovery of a large mass with hemorrhage, peritumoral edema, and a midline shift in the posterior horn of the right lateral ventricle. The patient was pathologically diagnosed with subependymoma after undergoing total tumor resection; a year after the surgery, he was free from tumor recurrence. Although symptomatic subependymomas are rare, they tend to show hemorrhage with peritumoral edema on neuroradiological tests and tend to be confused with high-grade brain tumors. In the present case, we highlight the importance of the appropriate diagnosis for subependymomas showing neuroradiological features that mimic high-grade gliomas. This diagnosis will help in providing suitable treatment for subependymomas.

Membrana de Liliequist: avaliação radiológica e suas implicações clínicas e terapêuticas / Liliequist membrane: radiological evaluation, clinical and therapeutic implications

A membrana de Liliequist, de maneira simplista e sucinta, pode ser entendida como uma projeção formada pela aracnoide que se estende do dorso da sela turca aos corpos mamilares. Apesar de se tratar de uma estrutura anatômica bem conhecida pelos neurocirurgiões, muitos radiologistas não a conhecem ou não valorizam seu estudo. A avaliação por imagem desta membrana é factível e pode ser interessante para o melhor planejamento pré-operatório, avaliação pós-operatória de terceiro-ventriculostomias e entendimento dos cistos aracnoides suprasselares e hemorragias perimesencefálicas. Ilustramos neste artigo os aspectos anatômicos da membrana, sobretudo do ponto de vista de imagem, além de suas possíveis implicações clinicocirúrgicas.

In a simplistic and succinct way, Liliequist membrane may be understood as a projection formed by an arachnoid membrane extending from the dorsum sellae to the mammillary bodies. In spite of being well known to neurosurgeons, many radiologists neither know this anatomical structure nor give importance to its study. The imaging evaluation of this membrane is feasible and may be interesting for a better preoperative planning; postoperative evaluation of third ventriculostomies; and understanding of suprasellar arachnoid cysts and perimesencephalic hemorrhage. The present article illustrates the anatomy of the membrane, with emphasis on imaging findings, besides describing its possible clinical and surgical implications.

Histopathological and immunohistochemical profile in anaplastic gangliogliomas.

BACKGROUND: The anaplastic ganglioglioma (AG) is the high-grade counterpart of ganglioglioma, a rare mixed tumor composed of neuronal/ganglion and glial cells. MATERIALS AND METHODS: We describe the histopathology and immunohistochemistry in 7 cases of AG and correlate them with the clinical and radiological features. RESULTS: Our AG patients correspond to 2.5% of the central nervous system tumor patients evaluated in our institution. The mean age at presentation was 25.7 years, with a male predominance. The most common clinical presentation was generalized tonic-clonic seizures (3/7 cases), in correlation with frequent cortical/subcortical location (6/7 cases). Histopathologically, all our cases showed high-grade features in glial (glial fibrillary acid protein-positive) and neuron-ganglion cells (synaptophysin, PGP-9.5, neurofilament, NSE and CD56-positive), as well as moderate cellularity, frequent mitotic figures and a Ki-67 labeling index >5%. All our patients had poor survival. CONCLUSION: We found that a typical histopathological and immunohistochemical profile is constant and can be useful in early diagnosis of these aggressive neoplasms.

Raupp: 50 years of neuroradiology / Raupp: 50 anos de neurorradiologia

OBJECTIVE: Evaluate the laboral and intellectual contributions of a founder of Brazilian Neuroradiology to the development of specialty. METHOD: Interviews were conducted with Dr. Raupp and contemporary doctors. Then we made a literature review with the Raupp search term aiming to identify those papers which included major changes in the diagnostic and therapeutic neurosurgical. RESULTS: The colleagues consulted were unanimous in recognizing the work of avant-garde and the importance of Dr. Raupp to the development of neuroradiological methods, especially in the pre-computed tomography fase. CONCLUSION: The work of Dr. Raupp was fundamental for the consolidation of Brazilian Neuroradiological School over the past five decades. He developed diagnostic and therapeutic techniques in congruence with the practices of the specialty on the global stage and he promoted education through medical residency programs.

OBJETIVO: Avaliar a contribuição laboral e intelectual de um dos fundadores da Neurorradiologia Brasileira para o desenvolvimento da especialidade. MÉTODO: Foram realizadas entrevistas com o Dr. Raupp e com médicos contemporâneos. Em seguida, foi feita uma revisão de literatura com o termo Raupp com o objetivo de identificar os trabalhos que definiram mudanças importantes na avaliação diagnóstica e terapêutica neurocirúrgica. RESULTADOS: Os colegas consultados foram unânimes no reconhecimento do trabalho de vanguarda e da importância do Dr. Raupp no desenvolvimento das técnicas neurorradiológicas, especialmente na fase pré-tomografia computadorizada. CONCLUSÃO: O trabalho do Dr. Raupp foi fundamental para a consolidação da Escola Neurorradiológica Brasileira ao longo das últimas cinco décadas. Ele desenvolveu técnicas diagnóstica e terapêutica em congruência com as práticas da especialidade no cenário mundial e promoveu o ensino através dos programas de residência médica.

Sinais em neurorradiologia: parte 1 / Signs in neuroradiology: part 1

O uso de sinais ou analogias na interpretação de imagens na radiologia médica é prática comum e antiga entre os radiologistas. Comparação entre achados de imagem com animais, alimentos ou objetos se faz de modo natural. Muitos sinais são bastante específicos e em alguns casos patognomônicos. Independentemente do grau de especificidade, sinais auxiliam a prática radiológica. Vários sinais já foram descritos em neurorradiologia. Neste artigo os autores demonstrarão 15 sinais neurorradiológicos. Serão abordados as principais características de cada um, a sua importância na prática clínica e os seus achados de imagem.

The use of signs or analogies for interpretation and description of medical images is an old and common practice among radiologists. Comparison of findings with animals, food or objects is not unprecedented and routinely performed. Many signs are quite specific and, in some cases, pathognomonic. Indeed, notwithstanding their degree of specificity, signs may help in the characterization of certain diseases. Several neuroradiological signs have been already described. The authors will present 15 neuroradiology signs in the present essay, approaching their main characteristics, the significance of their role in the clinical practice, as well as their respective imaging findings.

Sinais em neurorradiologia: parte 2 / Signs in neuroradiology: part 2

O uso de sinais na interpretação de imagens na neurorradiologia é extremamente útil. Muitos sinais são bastante específicos e em alguns casos, patognomônicos. Nesta segunda parte os autores descreverão 15 sinais neurorradiológicos adicionais. Serão novamente abordadas as principais características de imagem de cada um e sua importância na prática clínica.

The use of signs for interpretation of images in neuroradiology is extremely useful. Some signs are quite specific and, in some cases, pathognomonic. In this second part of their essay, the authors describe 15 additional neuroradiological signs. Main characteristics of imaging findings will be approached and the significance of their role in the clinical practice will be discussed.

Meios contínuos em neurocirurgia vascular e neurorradiologia intervencionista. Parte I / Mechanics of continuous media in vascular neurosurgery and endovascular neuroradiological procedures

Os aneurismas e as placas de ateroma compartem não somente um elevado índice de morbimortalidade, como também sua localização. Isso sugere que fatores hemodinâmicos contribuam no seu desenvolvimento. A quantificação de forças hemodinâmicas é complicada, especialmente em vasos intracranianos; porém, avanços recentes em mecânica computacional têm permitido calcular sua magnitude e distribuição em modelos arteriais com ajuda de técnicas de dinâmica de fluidos computacionais. No entanto, a compreensão desses modelos e a verificação de sua validade e limitações dependem do conhecimento de seu desenho e dos parâmetros hemodinâmicos utilizados. Por outro lado, a determinação das propriedades mecânicas das paredes arteriais é crucial, não somente para a compreensão das alterações do sistema cardiovascular no tempo e das causas responsáveis que dão origem às lesões vasculares, bem como para a realização da angioplastia, o planejamento de pontes arteriais e a seleção de próteses endovasculares. Dessa forma, a mais importante contribuição que podemos obter do conhecimento da biomecânica, em geral, e da mecânica dos meios contínuos, em particular, se encontra no melhor entendimento da fisiologia. Nesta revisão, passamos pelos conceitos fundamentais utilizados na formulação dos problemas da mecânica dos meios contínuos, com ênfase na pesquisa biomecânica das lesões vasculares, no intuito de oferecer algumas definições que promovam a análise crítica dos resultados nesse campo.

Cerebral aneurysms and atherosclerosis share not only a high rate of morbidity and mortality, but also its location. It suggests that hemodynamic factors contribute to their development. Quantification of hemodynamic forces is complicated, especially in intracranial arteries. However, recent advances in computational mechanics have allowed calculating the magnitude and distribution of these forces in arterial models with the help of techniques of computational fluid dynamics. However, the understanding of these models and verification of their validity and limitations depend on the knowledge of its design and hemodynamic parameters. Furthermore, the determination of mechanical properties of the arterial walls is crucial, not only for the understanding of the changes of the cardiovascular system in time and the causes of the injuries that they develop, as well as to the realization of angioplasty, planning of arterial bypass or the selection of endovascular prosthesis, for example. Thus, concepts on mechanics of continuous media are needed in the body of knowledge of all interested in cerebrovascular disease. In this review, we look the fundamental concepts used in the formulation of the problems of the mechanics of continuous media, focusing on biomechanics research of vascular lesions, in order to provide some definitions that promote the critical analysis of the results in this . The most important contribution that we can get from the knowledge of biomechanics, in general, and from the mechanics of continuous media, in particular, is a better understanding of physiology.

Advances in neuroimaging of stroke

This article reviews the recent advances in the neuroradiological diagnosis of acute stroke, highlighting the perspectives for the next 10 years. Key words: Brain infarction; cerebral hemorrhage; early diagnosis; neuroimaging.

O artigo sumaria os avanços recentes no diagnóstico neuroradiológico do acidente vascular cerebral isquêmico e hemorrágico, discutindo as perspectivas para a próxima década.