~1H magnetic resonance spectroscopy (~1H MRS) in the initially differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis / 中华放射学杂志

ABSTRACT

Objective To evaluate 1*"H magnetic resonance spectroscopy (1H MRS) in the differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis. Methods Fifteen patients who had clinical and CT, MRI changes that suggested a diagnosis of delayed cerebral necrosis or recurrent brain tumor after radiation therapy and 5 patients who had a definite clinical diagnosis of delayed cerebral necrosis underwent single voxel MR spectroscopy simultaneously both in the lesion′s region and the contralateral side. Results Of the former 15 cases who proved by surgicopathology, 14 cases were gliomas,1case was delayed cerebral necrosis, and their etiologic diagnoses of 1*"H MRS were correct. (1)1H MRS in 14 cases with gliomas exhibited specific spectral peaks including prominent choline-containing compounds (Cho), decreased or absent acetylaspartate(NAA) and total creatine (Cr),and the metabolic ratios showed significantly increased Cho/Cr, decreased NAA/Cr. Twelve cases showed abnormal lactate (Lac). (2)Among 6 cases with delayed cerebral necrosis, 5 cases exhibited decreased or absent Cho, NAA, Cr, and abnormal Lipid, 1 case showed absent Cho, NAA, and Cr with a flat curve without Lac. Conclusion 1H MRS was positively claimed for differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis.