Utilidad de la resonancia magnética en el diagnóstico del stroke agudo / Usefulness of magnetic resonance imaging in the diagnosis of acute stroke

Resumen El ataque cerebrovascular (ACV) es la primera causa de discapacidad y la tercera causa de muerte en la Argentina y en el mundo. La etiología del stroke es isquémica en su mayoría (más del 80% de los casos), siendo las causas más frecuentes las lesiones isquémicas de pequeños vasos de tipo lacunar y las tromboembólicas debido a ateroesclerosis de grandes arterias o cardioembolia. Las secuencias utilizadas en nuestro protocolo de estudio incluyen DWI, FLAIR, angio-RM 3D-TOF, SWI y FSE-T1 (tiempo aproximado de exploración de 13 minutos). Pueden observarse diferentes hallazgos en cada una de estas secuencias que son orientativos para determinar la etiología subyacente y estimar el tiempo de evolución de la lesión. En la actualidad, la trombectomía mecánica se ha convertido en el tratamiento de elección en pacientes seleccionados con accidente cerebral isquémico agudo. La transformación hemorrágica es la complicación más temida luego de la terapia de reperfusión intraarterial. La técnica de difusión de la resonancia magnética (RM) posee una mayor sensibilidad para detectar lesiones isquémicas, permite sospechar la etiología según el patrón lesional y aporta información valiosa para la selección de los pacientes candidatos a la reperfusión arterial.

Abstract Stroke or cerebrovascular attack (CVA) is the first cause of disability and the third cause of death in Argentina and in the world. The etiology of strokes is mostly ischemic (more than 80% of cases), with the most frequent causes being lacunar-type ischemic lesions of small vessels and thromboembolic lesions due to atherosclerosis of large arteries or cardioembolism. The sequences used in our study protocol include DWI, FLAIR, angio-RM 3D-TOF, SWI, and FSE-T1 (approximate scan time of 13 minutes). Different findings can be observed in each of these sequences that are indicative to determine the underlying etiology and estimate the time of evolution of the lesion. Currently, mechanical thrombectomy has become the treatment of choice in selected patients with acute ischemic stroke. Hemorrhagic transformation is the most feared complication after intra-arterial reperfusion therapy. The diffusion magnetic resonance technique is more sensitive for detecting ischemic lesions, allows one to suspect the etiology based on the lesion pattern, and provides valuable information for the selection of patients who are candidates for arterial reperfusion.

Diferenciación de la patología tumoral musculoesquelética benigna y maligna utilizando la técnica de difusión con resonancia magnética / Differentiation of benign and malignant musculoskeletal tumor pathology using the diffusion technique with magnetic resonance imaging

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.

Microeliminação da hepatite C na população carcerária: realmente possível? / Micro-elimination of hepatitis c in the incarcerated population: is it really possible?

ABSTRACT According to the World Health Organization, 71 million people live with chronic hepatitis C. The treatment of this disease requires assistance from specialized physicians and a highly complex health care system. The prison population has been recognized as being at a high risk of acquiring confinement-related infections, including viral hepatitis. Hepatitis C virus (HCV) infection is a primary cause of death owing to liver disease among liberty-deprived individuals. Generally, prisons do not have adequate isolation wards for persons with communicable diseases, and overcrowding is a risk factor for this population. Besides prison overcrowding, violence, poor sanitary conditions, low socioeconomic status, social isolation, and emotional instability are factors that can lead detainees to adopt unhealthy habits that make them more susceptible to infections, including HCV, and complicate effective treatment. The Criminal Execution Law 7, 210 of July 11, 1984, in Article 14, grants preventive and curative medical, dental, and pharmacological healthcare to detainees. However, adequate hepatitis C treatment is rarely provided at prisons owing to social stigma and lack of knowledge on the severity of this condition or because most detainees are unaware of their condition. Given the multiple limitations imposed by the prison system model, implementing measures to treat diseases effectively is challenging. However, it is possible to eliminate hepatitis C in prisons in the long term through the coordinated action of public health institutions and the prison system.

RESUMO De acordo com a Organização Mundial da Saúde, 71 milhões de pessoas vivem com hepatite C crônica. O tratamento dessa doença requer assistência de médicos especializados e um sistema de saúde de alta complexidade. A população carcerária tem sido reconhecida como sendo de alto risco de adquirir infecções relacionadas às condições de confinamento, incluindo hepatites virais. O vírus da hepatite C (VHC) é uma causa primária de morte por doença hepática em pessoas privadas de liberdade. Geralmente, as prisões não possuem locais adequados para isolamento de pessoas com doenças transmissíveis e a superlotação é um fator de risco para essa população. Além da superlotação das prisões, violência, más condições sanitárias, baixo nível socioeconômico, isolamento social e instabilidade emocional são motivos adicionais que induzem os detidos a praticar hábitos não saudáveis, que os tornam mais suscetíveis a certas infecções (incluindo VHC) e complicam o tratamento específico. A Lei de Execução Penal n. 7.210, de 11 de julho de 1984, em seu artigo 14, garante assistência preventiva e curativa à saúde, incluindo assistência médica, farmacêutica e odontológica aos detidos. No entanto, o tratamento adequado da hepatite C é raramente fornecido nas prisões devido estigma social ou falta de conhecimento de sua condição ou porque a maioria dos detidos não tem conhecimento de sua condição. Devido a múltiplas limitações impostas pelo modelo prisional, a implementação de medidas para o tratamento eficaz de doenças é desafiadora. No entanto, é possível eliminar a hepatite C em um ambiente prisional de longa permanência através de ações coordenadas de instituições de saúde pública e o sistema prisional.

Extracerebral Pterional Metastasis from Malignant Meningioma: A Case Report

Anaplastic or malignant meningiomas that are classified as World Health Organization (WHO) grade III account for less than 1% of all meningiomas diagnosed. Despite the aggressive course, distant metastases are a rarity, occurring in only 0.1% to 0.2% of cases. We report the case of a 56-year-old woman who presented with parasagittal benign meningioma that underwent malignant transformation along with metastasis into the right orbitosphenoid region. The clinical, radiological, and histopathological aspects are highlighted, with an emphasis on the natural history of meningiomas.

Characterization of electrocorticographic, electromyographic and electrocardiographic recordings after the use of caffeine in Wistar rats / Caracterização dos registros eletrocorticográficos, eletromiográficos e eletrocardiográficos após uso de cafeína em ratos Wistar

ABSTRACT Objective: To describe electrocorticographic, electromyographic and electrocardiographic profiles to report the electrophysiological effects of caffeine in Wistar rats. Methods: Male adult Wistar rats weighing 230g to 250g were used. Rats were allocated to one of two groups, as follows: Group 1, Control, intraperitoneal injection of 0.9% saline solution (n=27); and Group 2, treated with intraperitoneal injection of caffeine (50mg/kg; n=27). The rats were submitted to electrocorticographic, electromyographic and electrocardiographic assessment. Results: Brain oscillations (delta, theta, alpha, beta and gamma) in the frequency range up to 40Hz varied after caffeine administration to rats. Powers in delta and theta oscillations ranges were preponderant. The contractile force of the skeletal striated and cardiac muscles increased. Electrocardiogram analysis revealed shorter RR, QRS and QT intervals under the effect of caffeine. Conclusion: In the central nervous system, there was an increase in the delta, theta and alpha amplitude spectrum, which are related to memory encoding and enhanced learning. With regard to skeletal muscle, increased contraction of the gastrocnemius muscle was demonstrated, a clear indication of how caffeine can be used to enhance performance of some physical activities. Electrocardiographic changes observed after caffeine administration are primarily related to increased heart rate and energy consumption.

RESUMO Objetivo: Descrever os perfis eletrocorticográficos, eletromiográficos e eletrocardiográficos para relatar os efeitos eletrofisiológicos da cafeína em ratos Wistar. Métodos: Foram utilizados ratos Wistar, machos, adultos, pesando de 230g a 250g. Os animais foram divididos nos seguintes grupos: Grupo 1, Controle com solução fisiológica 0,9% por via intraperitoneal (n=27), e Grupo 2, Tratado com Cafeína (50mg/kg intraperitoneal; n=27). Foram realizadas avaliações por eletrocorticograma, eletromiograma e eletrocardiograma. Resultados: Houve variações nas oscilações cerebrais (delta, teta, alfa, beta e gama) na faixa de frequência de até 40Hz após a aplicação de cafeína em ratos. Observou-se que as potências nas faixas das oscilações delta e teta foram preponderantes. A força de contração nos músculos estriado esquelético e cardíaco aumentou. A avaliação do eletrocardiograma demonstrou que a duração dos intervalos RR, QRS e QT foram menores na presença da cafeína. Conclusão: No sistema nervoso central, houve aumento dos espectros de amplitude delta, teta e alfa, que auxiliam na codificação das memórias e estão relacionados à melhora do aprendizado. Em relação à musculatura esquelética, demonstrou-se aumento da contração do músculo gastrocnêmio, uma clara indicação de como a cafeína pode ser usada para aumentar o desempenho em algumas atividades físicas. As alterações eletrocardiográficas observadas após a administração de cafeína estiveram relacionadas principalmente ao aumento da frequência cardíaca e do consumo de energia.

Hemifacial Spasm Associated with Chiari Type I Malformation: Surgical Considerations and Case Report

Hemifacial spasm (HS) is a movement disorder characterized by paroxysmal and irregular contractions of the muscles innervated by the facial nerve. Chiari malformation type I (CM I) is a congenital disease characterized by caudal migration of the cerebellar tonsils, and surgical decompression of foramen magnum structures has been used for treatment. The association of HS with CM I is rare, and its pathophysiology and therapeutics are speculative. There are only a few cases reported in the literature concerning this association. The decompression of the posterior fossa for the treatment of CM I has been reported to relieve the symptoms of HS, suggesting a relation between these diseases. However, the possible complications of posterior fossa surgery cannot be underrated. We report the case of a 66-year-old patient, in ambulatory follow-up due to right HS, no longer responding to botulinum toxin treatment. Magnetic resonance imaging (MRI) of the skull revealed compression of the facial nerve and CM I. The patient underwent surgery for HS by neurovascular microdecompression of the facial nerve via right lateral suboccipital craniectomy, but presented significant clinical worsening in the postoperative period even though the cerebellum edema related to surgical manipulation was mild. Due to the clinical worsening, the patient underwent a median suboccipital craniectomy with decompression of the foramenmagnum structures. After this second surgery, the patient had progressive improvement and was discharged from the hospital for ambulatory care.

Rupturas agudas de ligamento cruzado anterior. ¿Existe la cicatrización espontánea? / Anterior cruciate ligament acute ruptures. Is there spontaneous healing?

OBJETIVOS: Identificar pacientes que, con diagnóstico de ruptura aguda y completa del LCA, cicatrizaron espontáneamente; y si esta curación tiene relación con la edad, sexo, tipo de ruptura, tiempo de reposo y mecanismos del trauma. MATERIALES Y MÉTODOS: Se evaluaron 30 pacientes con ruptura aguda completa del LCA mediante diagnóstico clínico e imagenológico con resonancia magnética nuclear (RMN). Se utilizó para valoración subjetiva test de Lysholm e IKDC 2000. RESULTADOS: Todos los pacientes mejoraron de la primera a la segunda consulta, con resultados: Lachman (p<0.0406), pivot shift (p=0.071) y cajón anterior (p<0.001). En la segunda RMN de control, se observó el LCA con signos de cicatrización en la totalidad de los pacientes. Podría inferirse, con un seguimiento promedio de 12 meses para hombres (IC95% 6-17) y de 13 meses para las mujeres (IC95% 31max), una recuperación clínica prácticamente completa, así como también que la cicatrización se produciría independientemente de variables como la edad, sexo o tratamiento específico (p=0.795 y p=0.841). CONCLUSIÓN: A pesar de la limitación del tamaño del presente estudio, los objetivos planteados fueron alcanzados. Existiría la cicatrización espontánea del LCA y la misma no estaría asociada a la edad, sexo, ni a tratamientos específicos de fisioterapia o al uso de inmovilizadores; aunque sí, al reposo durante los primeros 3 meses post lesión. Tipo de estudio: Retrospectivo. Nivel de evidencia: IV.

OBJECTIVES: To identify patients who, with a diagnosis of acute and complete ACL rupture, healed spontaneously, and determine whether such healing is related to age, sex, type of rupture, resting time, and mechanisms of trauma. MATERIALS AND METHODS: Thirty patients with complete acute ACL rupture were evaluated by clinical diagnosis and Magnetic Resonance Image (MRI). Both Lysholm test and IKDC 2000 were used for subjective evaluation. RESULTS: All patients improved from the first to the second consultation, with results: Lachman (p <0.0406), pivot shift (p = 0.071), and anterior drawer (p <0.001). In the second control MRI, ACL with signs of healing in all patients were observed. With an average follow-up of 12 months for men (95% CI 6-17) and 13 months for women (95% CI 31max), a practically complete clinical recovery could be inferred, as well as healing taking place independently of variables such as age, sex, or specific treatment (p = 0.795 and p = 0.841). CONCLUSION: Despite the size limitation for the present study, the objectives set were achieved. There would be spontaneous ACL healing associated with a 3-month-post-injury resting time, but dissociated from age, sex, specific physiotherapy treatments, or the use of immobilizers. Type of study: Retrospective. Level of evidence: IV.