脑胶质瘤外科手术后辅助放疗的MR波谱随访研究

Follow-up MR spectroscopic study of adjuvant radiotherapy after surgery of brain glioma

目的:探讨脑胶质瘤外科手术后辅助放射治疗的MR波谱变化趋势和可能的病理学基础。方法:搜集23例经手术病理证实的胶质瘤患者,术后均接受辅助放射治疗,监测脑组织、部分病例的残留肿瘤及复发肿瘤的代谢物浓度的变化趋势,并与放疗结束时的自身数据进行比较。结果:放射野内脑组织NAA/Cr、Cho/Cr和NAA/Cho值逐步降低,至放疗结束后第3个月达最低水平,分别为1.83±0.16、1.27±0.10和1.02±0.15,然后逐渐升高至接近放疗前水平,分别为1.73±0.17、1.45±0.07和1.31±0.18,差异具有统计学意义(F值分别为305.20、50.62和266.68,P值均<0.01)。7例残留瘤体中5例未复发,3种代谢物比值放疗后有所降低并保持在一定水平,2例复发者放疗结束后第12个月NAA/Cr、Cho/Cr和NAA/Cho值分别为0.20±0.13、3.45±0.11和0.12±0.10,表明肿瘤细胞增值活跃,代谢旺盛,高度提示肿瘤复发,与第二次手术病理结果具有较好的一致性。结论:磁共振波谱通过监测代谢物浓度变化,能无创性反映胶质瘤术后放疗脑损伤的修复过程,监测残留瘤体放疗后的生物活性,可为诊断肿瘤复发提供有价值的信息。

Objective：To investigate the change of MRS and possible pathological basis of brain glioma after surgery in addition with adjuvant radiation therapy. Methods： 23 cases of glioma with surgery and pathology confirmed glioma of brain underwent adjuvant postoperative radiotherapy. MRS was used to monitor the metabolite changes of brain tissue, re- sidual tumor and recurrent tumor, and comparisons were made based on MRS data. Result： MRS showed that NAA/Cr, Cho/Cr and NAA/Cho values of brain tissue within radiation field reduced gradually,which reached the lowest point at the end of the first 3 months after radiotherapy,which were 1. 83±0.16,1.27±0.10,and 1.02±0.15 respectively. Then,in- creased gradually and almost reached the level before radiotherapy, which were 1.73 ±0.17,1.45 ± 0.07, and 1.31 ±0.18, respectively,with statistically significant difference （F value was 305.20,50.62 and 266.68 respectively,P〈0.01）. No re- currence was found in 5 of 7 cases with residual tumors the three metabolites ratio decreased after radiotherapy and maintain in a certain level;in 2 cases with recurrence,the NAA/Cr,Cho/Cr and NAA/Cho values were 0. 20±0.13,3. 45±0.11 ,and 0.12 ± 0.10, respectively at 12 months after radiotherapy,indicating that this tumor had active proliferation and high metab- olism,there was a good correlation with the pathology of second surgery. Conclusion： Via the monitoring of the change of metabolites, MRS can monitor the repair process of radiation injury of brain non-invasively after surgery treatment of glio- ma,which provides valuable information in the diagnosis of tumor recurrence.