Phosphorus magnetic resonance spectroscopy in malformations of cortical development

Abstract

Introduction:Malformations of cortical development (MCD) result from disruptions in the dynamic process of cerebral corticogenesis and are important causes of epilepsy, motor deficits and cognitive impairment. Objectives: The aim of this study was to evaluate phospholipids metabolism in vivo in a series of patients with epilepsy and MCD. Methods: Thirty-seven patients with MCD and 31 control subjects were studied using three-dimensional phosphorus magnetic resonance spectroscopy ( 31 P-MRS) at a 3.0 T scanner. Quantification methods were applied to the following resonances: phosphoethanolamine (PE), phosphocholine (PC), glycerophosphoethanolamine (GPE), glycerophosphocholine (GPC), inorganic phosphate (Pi), phosphocreatine (PCr), and a-, b-, and g-adenosine triphosphate (ATP). The magnesium (Mg 2+ ) levels and pH were calculated based on PCr, Pi and b-ATP chemical shifts. Results: Compared to controls, the MCD lesions exhibited lower pH values and higher Mg 2+ levels (p<0.05). The lesions also presented significant reduction of GPC and PDE, and an increased PME/PDE ratio. The otherwise normal appearing parenchyma also demonstrated lower pH values in the frontoparietal cortex and bilateral centrum semiovale. Conclusions: Our data support the idea that metabolic impairments occur in the lesions of MCD, with propagation to remote normal appearing parenchyma. The results also suggest that there are membrane turnover disturbances in MCD lesions.

PCr/ATP ratio mapping of the human head by simultaneously imaging of multiple spectral peaks with interleaved excitations and flexible twisted projection imaging readout trajectories at 9.4 T

“…The average PCr/γ‐ATP ratios over the entire brain region for each of the three volunteers are 1.46 ± 0.27, 1.43 ± 0.26, and 1.46 ± 0.31, respectively. These ratios are in general agreement with literature values considering that the large voxel size permits partial volume effects across muscle‐brain boundaries (6, 19). Figure 4f shows the superposition of the partially transparent PCr/γ‐ATP ratio (red) over the corresponding 23 Na images.…”

Brain aging: Evaluation of pH using phosphorus magnetic resonance spectroscopy

“…In the group of young people, it was 7.09 ± 0.11, and in the older group pH was 7.03 ± 0.05. These average pH values for both groups are consistent with previous studies that found that the brain pH in a healthy person is in the range of 6.96–7.11 …”

“…These average pH values for both groups are consistent with previous studies that found that the brain pH in a healthy person is in the range of 6.96-7.11. 8,12 Similar results were obtained by Forester et al and Murashita et al 5,6 In both studies, it was found that the brain acidity increases with age (pH decreases). Forester et al examined people aged 21-84 years and showed that the concentration of H + ions in the brain grows at the rate of 0.53% per decade, so the brain pH decreases by 2.41 × 10 −3 per decade which, over the decades, can result in a significant change in pH.…”

Variabilidad clínica de la polimicrogiria: a propósito de 35 nuevos casos y revisión de la bibliografía

“…Pese a no poder establecer una sospecha fundamentada en los criterios de Barkovich, el diagnóstico se confirmó mediante análisis histológico, prueba que sigue siendo la única que establece el diagnóstico definitivo cuando es posible realizarla [5,6,[35][36][37]. En un futuro no muy lejano, la implementación sistematizada de la tractografía (incorporando la medición de la fracción de anisotropía y el cálculo de la difusividad media), la incorporación de los equipos de 3 T (en un futuro, 7 T), así como el uso de otras técnicas de medicina nuclear, nos permitan aumentar la sensibilidad para realizar el diagnóstico de polimicrogiria en vida [33,[38][39][40][41].…”