Consistent spatial lesion-symptom patterns: A comprehensive analysis using triangulation in lesion-symptom mapping in a cohort of stroke patients.

INTRODUCTION: The relationship between brain lesions and stroke outcomes is crucial for advancing patient prognosis and developing effective therapies. Stroke is a leading cause of disability worldwide, and it is important to understand the neurological basis of its varied symptomatology. Lesion-symptom mapping (LSM) methods provide a means to identify brain areas that are strongly associated with specific symptoms. However, inner variations in LSM methods can yield different results. To address this, our study aimed to characterize the lesion-symptom mapping variability using three different LSM methods. Specifically, we sought to determine a lesion symptom core across LSM approaches enhancing the robustness of the analysis and removing potential spatial bias. MATERIAL & METHODS: A cohort consisting of 35 patients with either right- or left-sided middle cerebral artery strokes were enrolled and evaluated using the NIHSS at 24 h post-stroke. Anatomical T1w MRI scans were also obtained 24 h post-stroke. Lesion masks were segmented manually and three distinctive LSM methods were implemented: ROI correlation-based, univariate, and multivariate approaches. RESULTS: The results of the LSM analyses showed substantial spatial differences in the extension of each of the three lesion maps. However, upon overlaying all three lesion-symptom maps, a consistent lesion core emerged, corresponding to the territory associated with elevated NIHSS scores. This finding not only enhances the spatial accuracy of the lesion map but also underscores its clinical relevance. CONCLUSION: This study underscores the significance of exploring complementary LSM approaches to investigate the association between brain lesions and stroke outcomes. By utilizing multiple methods, we can increase the robustness of our results, effectively addressing and neutralizing potential spatial bias introduced by each individual method. Such an approach holds promise for enhancing our understanding of stroke pathophysiology and optimizing patient care strategies.

Imagen del tensor de difusión de la vía corticoespinal y su asociación con el pronóstico del infarto cerebral agudo: experiencia de una cohorte en México / Diffusion tensor imaging of the corticospinal pathway and its association with the prognosis of acute cerebral infarction: experience with a cohort in Mexico

INTRODUCCIÓN: La imagen del tensor de difusión por resonancia magnética a través de la fracción de anisotropía permite evaluar la integridad de las vías motoras después de un infarto cerebral. OBJETIVO: Correlacionar la fracción de anisotropía con las escalas clínicas y el pronóstico del infarto cerebral. Sujetos y métodos: Estudio prospectivo de pacientes con infarto cerebral para comparar la fracción de anisotropía en diferentes regiones de interés con evaluaciones funcionales y con controles sin infarto. En un subgrupo con rehabilitación, se realizó una resonancia magnética inicial y a los tres meses, con un seguimiento clínico durante seis meses. RESULTADOS: Se incluyó a 38 pacientes consecutivos con infarto cerebral de la arteria cerebral media. Los valores de la fracción de anisotropía fueron menores en la vía corticoespinal ipsilateral que en la vía corticoespinal de los controles. Los valores de la fracción de anisotropía en la vía corticoespinal ipsilateral se asociaron con el valor de la escala funcional en el momento de su admisión. Los cambios en los valores de la fracción de anisotropía entre la resonancia magnética inicial y a los tres meses se correlacionaron con la puntuación en la escala funcional y en la escala de Rankin modificada a los tres y a los seis meses. CONCLUSIONES: El valor de la fracción de anisotropía en la cápsula interna ipsilateral se asocia a la presencia de lesión y a su presentación clínica. Los cambios en la fracción de anisotropía a los tres meses sugieren la recuperación clínica a largo plazo

INTRODUCTION: Magnetic resonance diffusion tensor imaging through the fraction of anisotropy allows evaluation of the integrity of the motor pathways after cerebral infarction. AIMS. To correlate the fraction of anisotropy with the clinical scales and the prognosis of cerebral infarction. SUBJECTS AND METHODS: Prospective study of patients with cerebral infarction to compare the fraction of anisotropy in different regions of interest with functional evaluations and with controls free of infarction. A subgroup of subjects with rehabilitation underwent an initial MRI scan and another at three months, with clinical follow-up for six months. RESULTS: Thirty-eight consecutive patients with middle cerebral artery infarction were included. The fraction of anisotropy values were lower in the ipsilateral corticospinal pathway than the fraction of anisotropy of the corticospinal pathway of the controls. The values of the fraction of anisotropy in the ipsilateral corticospinal pathway were associated with the value of the functional scale on admission. Changes in the fraction of anisotropy values between the initial MRI and the scan performed at three months correlated with the score on the functional scale and the modified Rankin scale at three and six months. CONCLUSIONS: The value of the fraction of anisotropy in the ipsilateral internal capsule is associated with the presence of a lesion and with its presenting symptoms. Changes in the fraction of anisotropy at three months suggest long-term clinical recovery

Novel Oral Anticoagulants as Treatment for Vertebral Artery Dissection: Case Report.

BACKGROUND AND PURPOSE: Cervical artery dissections, which may be traumatic or spontaneous, account for a significant proportion of strokes in the young. Antithrombotic therapy is the mainstay of treatment, but new oral anticoagulants could be an alternative treatment to the optimal strategy of anticoagulation followed by antiplatelet drugs. SUMMARY OF CASE: We report the case of a 40-year-old patient with a spontaneous vertebral artery dissection who developed a cerebellar ischemic stroke, who had a favorable outcome and complete vessel recanalization after three months of treatment with the oral factor Xa inhibitor rivaroxaban. CONCLUSION: New oral anticoagulant could constitute an alternative and new therapeutic option in cervical artery dissections.

Intrathecal gadodiamide for identifying subarachnoid and ventricular neurocysticercosis.

OBJECTIVE: Some neurocysticercosis cysts may remain hidden despite novel MRI sequences. This study evaluates the diagnostic value of gadodiamide (GDD)-contrasted MRI cisternography in selected cases of neurocysticercosis. METHODS: We included patients aged 18-65 years with a probable diagnosis of subarachnoid cysticercosis in whom previous neuroimaging studies failed to demonstrate the presence of cysts. One millilitre of GDD was administered intrathecally as a contrast agent with subsequent performance of MRI. RESULTS: Fourteen patients were included. Optimal contrast diffusion was achieved in nine patients, and partial diffusion was achieved in 4. Intracranial vesicles were identified in 10 patients, with the presence of more than 60 basal subarachnoid vesicles being revealed in all, with five cysts in the fourth ventricle in four patients and a floating cyst in the lateral ventricle in one. In one case, intrathecal GDD demonstrated spinal cysticercosis. No adverse events were reported after intrathecal GDD administration. CONCLUSIONS: Intrathecal GDD administration is useful for the diagnosis of subarachnoid and intraventricular neurocysticercosis and can be used to improve diagnostic accuracy in selected cases.

Nocardia abscess during treatment of brain toxoplasmosis in a patient with aids, utility of proton MR spectroscopy and diffusion-weighted imaging in diagnosis.

We report the case of a 30-year-old man with known HIV-positive status who developed, 4 months prior to admission, recurrent left partial motor seizures followed by left hemiparesis. At another hospital, contrasted CT scan of the head revealed right frontal hypodense lesion with mass effect and focal contrast enhancement. A small left occipital lesion was also present. HIV-associated brain toxoplasmosis was considered and phenytoin, pyrimethamine, clindamycin and antiretrovirals were administered. Hemiparesis improved but, 3 weeks prior to admission, he developed progressive headache and bilateral visual defects. Upon admission to our center, he was found with left homonymous hemianopsia, right hemiparesis and a large hypodense left occipital lesion on a head CT scan. Proton MR spectroscopy showed lactate at 1.3ppm, amino acids at 0.9ppm, and diffusion-weighted imaging (DWI) revealed hyperintensity at the lesion, suggesting a pyogenic abscess. Aspiration yielded purulent material and Nocardia asteroides grew in culture. The patient was treated with trimethoprim-sulfametoxazole and recovered with a mild visual field residual defect.

Estudio de sensibilidad y especificidad de la biopsia por aspiración con aguja fina guiada por tomografía en tumores intracavitarios / Sensitivity and specificity study of fine needle aspiration biopsy by CT scan

Objetivo: Demostrar la utilidad de la tomografía computada como método guía en la biopsia por aspiración con aguja fina. Material y métodos: Estudio descriptivo-retrospectivo. Se incluyeron 30 procedimientos de biopsia por aspiración con aguja fina guiada por tomografía computada, en 28 pacientes con edades de entre 30 y 90 años, en tumores de órganos intracavitarios. Resultados: En el 80 por ciento de las muestras se obtuvo material adecuado; la especificidad para malignidad fue de 100 por ciento y la sensibilidad de 83 por ciento. Conclusiones: La tomografía computada es un método útil como guía en procedimientos no invasivos. La biopsia por aspiración con aguja fina permite distinguir entre lesiones neoplásicas y no neoplásicas, ayuda a proporcionar un tratamiento oportuno, dirigido, con menor costo y estancia hospitalaria. Tiene un bajo índice de complicaciones y una alta certeza diagnóstica.