[Magnetic resonance imaging with spectroscopy, perfusion and cerebral diffusion in the diagnosis of brain tumours]. / Resonancia magnética con espectroscopia, perfusión y difusión cerebral en el diagnóstico de los tumores cerebrales.

AIM: We review three of the most important functional techniques in magnetic resonance imaging, it means spectroscopy, perfusion and diffusion; we do emphasize in its applications, particularly in the diagnostic and treatment of brain tumors. First, we discuss the physical principles and results interpretation of each technique. After that, we discuss its major applications. DEVELOPMENT AND CONCLUSIONS: Choline containing compounds using contralateral creatine and choline for normalization or ipsilateral N-acetyl-aspartate appeared to correlate best with the degree of tumor infiltration, regardless o tumor histological grade. Magnetic resonance spectroscopy imaging (MRSI) seems more accurate than conventional magnetic resonance imaging (MRI) in defining indistinct tumor boundaries and quantifying the degree of tumor infiltration. MRSI is the choice of site within a lesion for biopsy and use in image-guided therapy, including definition of radiation ports. Angiogenesis, and increased vascular permeability, are characteristic of cerebral neoplasms; these processes can be imaged using perfusion MRI. Most commonly, tumor perfusion is measured using rapid gradient T2-weighted imaging during bolus injection of gadolinium dimeglumine gadopentetate. Care has to be taken to avoid blood-brain barrier leakage affecting perfusion results. Pharmacokinetic models are available for estimation of blood-brain permeability. Cerebral blood volume increases with tumor grade, and maybe helpful in identifying tumor recurrence, and peri-tumoral edema, and distinguishing malignant from benign lesions.

Tuberculosis diseminada con afectación grave del sistema nervioso central poco sintomática / Almost symptom free disseminated tuberculosis severely affecting the central nervous system

No disponible

Resonancia magnética con espectroscopia, perfusión y difusión cerebral en el diagnóstico de los tumores cerebrales / Magnetic resonance imaging with spectroscopy, perfusion and cerebral diffusion in the diagnosis of brain tumours

Objetivo. Se revisan las técnicas de espectroscopia, perfusión y difusión por resonancia magnética (RM), haciendo particular énfasis en sus aplicaciones para el diagnóstico y tratamiento de los tumores cerebrales. Se discuten los principios físicos de cada técnica y el significado e interpretación de sus resultados, dejando en última instancia sus principales aplicaciones. Desarrollo y conclusiones. Las lesiones que contienen colina relacionadas con la creatina y con la colina del hemisferio contralateral, así como el N-acetil-aspartato ipsilateral, tienen buena correlación con el grado de infiltración o grado histológico tumoral. La espectroscopia por RM es más precisa que la RM convencional para definir los márgenes tumorales y cuantificar el grado de infiltración tumoral. La espectroscopia por RM está indicada para seleccionar el lugar donde se debe realizar la biopsia o biopsia estereotáxica, así como para definir la zona a irradiar. La angiogénesis y el incremento dela permeabilidad vascular son característicos de las neoplasias cerebrales; esto se puede reproducir con la utilización de la perfusión por RM. Habitualmente, la perfusión tumoral se mide usando imágenes rápidas en gradiente T2 durante el paso de un bolo de contraste paramagnético intravenoso. Los resultados pueden verse afectados si existe una ruptura de la barrera hematoencefálica. Pueden utilizarse modelos farmacocinéticos para estimar la permeabilidad de la barrera. El volumen sanguíneo cerebral se incrementa con el grado tumoral, pudiendo servir de ayuda para identifica recidivas tumorales o el edema perilesional y diferenciar lesiones malignas de benignas (AU)

Aim. We review three of the most important functional techniques in magnetic resonance imaging, it means spectroscopy, perfusion and diffusion; we do emphasize in its applications, particularly in the diagnostic and treatment of brain tumors. First, we discuss the physical principles and results interpretation of each technique. After that, we discuss its major applications. Development and conclusions. Choline containing compounds using contralateral creatine and choline for normalization or ipsilateral N-acetyl-aspartate appeared to correlate best with the degree of tumor infiltration, regardless o tumor histological grade. Magnetic resonance spectroscopy imaging (MRSI) seems more accurate than conventional magnetic resonance imaging (MRI) in defining indistinct tumor boundaries and quantifying the degree of tumor infiltration. MRSI is the choice of site within a lesion for biopsy and use in image-guided therapy, including definition of radiation ports. Angiogenesis,and increased vascular permeability, are characteristic of cerebral neoplasms; these processes can be imaged using perfusion MRI. Most commonly, tumor perfusion is measured using rapid gradient T2-weighted imaging during bolus injection ofgadolinium dimeglumine gadopentetate. Care has to be taken to avoid blood-brain barrier leakage affecting perfusion results. Pharmacokinetic models are available for estimation of blood-brain permeability. Cerebral blood volume increases with tumor grade, and maybe helpful in identifying tumor recurrence, and peri-tumoral edema, and distinguishing malignant from benign lesions (AU)

Arteritis sifilítica cerebral: remisión completa tras tratamiento adecuado / Syphilitic cerebral arteritis. Complete remission after adequate treatment

No disponible