MR弥散、灌注成像及1H-MRS在判断脑肿瘤放疗后坏死与肿瘤复发诊断中的应用

目的 :试探讨弥散、灌注成像及1H MRS在放射性坏死与脑肿瘤复发鉴别诊断中的作用。材料和方法 :对象 :肿瘤复发和放射性坏死的脑肿瘤患者 2 8例 ,男 17例 ,女 11例。年龄 12～ 6 6岁。检查方法 :MR弥散、灌注成像和1H MRS检查。结果 :脑肿瘤复发 16例 ,放射性坏死 12例。影像表现 :脑肿瘤复发 :弥散成像信号多样 ;灌注成像 :局部高信号 ;1H MRS :Cho上升 ,NAA下降 ,以Lip Lac波升高。放射性坏死 :弥散成像信号多样 ;灌注成像低信号 ;1H MRS :Cho、NAA、Cr均较低。结论 :MRI弥散、灌注成像及1H MRS对判断脑肿瘤放疗后坏死还是肿瘤复发有意义。

Combination of Perfusion, Diffusion MR Imaging, and 1HMRS in the Differentiation of Necrosis and Recurrence of Brain neoplasm after Radiotherapy

Purpose: To evaluate 1H Magnetic resonance spectroscopy ( 1HMRS) perfusion MR, and diffusion MR in the differentiation of necrosis and recurrence of brain neoplasm after radiotherapy. Materials and methods: 28 cases of patients suffered from brain neoplasm were selected, all of them had the indication of necrosis or recurrence after radiotherapy. In which, there were 17 male and 11 female, the age ranged from 12 to 66 years. Perfusion MR, diffusion MR, and 1HMRS were performed in all 28 cases. Results: There were 16 cases of recurrence of brain neoplasm, as well as 12 cases of necrosis after radiotherapy. 1. The imaging manifestation of neoplasm recurrence appeared as follow: Diverse intensities were present on diffusion imaging; whereas topical hyper intense were present on perfusion imaging. The rise of peak of choline, the fall of peak of N acetyiaspatate, as well as the sharp rise of peak of lipid lactate, in which was mainly composed of lipid were present in 1HMRS. 2. The imaging manifestation of neoplasm necrosis appeared as follow: Diverse intensities were present on diffusion imaging; whereas hypo intense was present on perfusion imaging; all of peaks of choline, N acetylaspartate, and creatine were descended. Conclusion: Combination of perfusion, diffusion, and 1HMRS is a helpful method to detemine recurence or necrosis of brain neoplasm after radiotherapy.