摘要
目的探讨鼻咽癌放疗后颞叶放射性损伤组织水分子弥散能力的变化。方法选取60例志愿者作为正常对照组(Ⅰ组),30例鼻咽癌放疗后MRI无异常改变患者作为放疗后微观损伤组(Ⅱ组),30例鼻咽癌放疗后MRI有异常改变患者作为颞叶损伤组(Ⅲ组)。进行常规MRI T1WI、T2WI成像和弥散加权成像(diffusion weighted imaging,DWI),分别测量颞叶的表观扩散系数(ADC)值,然后进行比较。结果正常对照组、微观损伤组和颞叶损伤组的平均ADC值(ADCav)分别为(0.82±0.08)×10-3,(0.76±0.12)×10-3,(2.08±0.33)×10-3mm2/s。放疗后微观损伤组的AD-Cav值小于正常对照组,差异有显著性(P<0.05);颞叶损伤组的ADCav值分别大于正常对照组和放疗后微观损伤组,差异有显著性(P<0.0001)。结论鼻咽癌放疗后,尽管MRI显示颞叶正常,但ADCav值减小,反映受照区域水分子的弥散能力降低,可能与细胞毒性水肿有关。当出现放射性脑损伤后,ADCav值明显升高,反映损伤组织水分子的弥散能力增加。DWI成像既可以敏感地显示放射性颞叶损伤的出现,又可以通过测量ADCav值定量分析损伤的程度,为放射性脑病的早期发现和提前干预性治疗提供了可能。
Objective To explore the changes of diffusion of water molecules in temporal lobe radiation injury following radiotherapy for nasopharyngeal carcinoma. Methods Sixty healthy volunteers were selected as control group,30 cases of nasopharyngeal carcinoma（NPC） after radiotherapy but without temporal lobe abnormal changes on MRI served as micro-injury group and 30 cases of temporal lobe injury following radiotherapy served as injury group. All of them were examined with routine MRI and diffusion weighted imaging （DWI） and the apparent diffusion coefficient（ADC） values of temporal lobe were measured. The aver- age ADC values（ADCav）were compared between groups. Results The ADCav values of control group, micro-injury group and injury group were （0.82±0.08）×10^-3,（0.76±0.12）×10^-3,and （2.08±0.33）×10^-3mm^2/s respectively. The ADCav value in micro-injury group after radiotherapy was lower than that in control group and has statistically significant difference between them（ P 〈 0.05 ）. The ADCav value in injury group was higher than that in micro-injury group after radiotherapy and control group respectively and had statistically significant differences between them（P 〈 0.0001 ）. Conclusion After radiotherapy of nasopharyngeal carcinoma, the ADCav value of temporal lobe decreases, reflecting the water molecule diffusion reduction. It may be related to cytotoxic edema. After radiation injury appears, the ADCav values increase, reflecting the water molecule diffusion enhancement. Diffusion weighted imaging can sensitively display radiation injury of temporal lobe, and can quantitatively analyse damage degree by means of measuring ADC values,providing the possibility to detect radiation injuries in earlier period and management in time.
出处
《中国肿瘤临床与康复》
2007年第5期385-388,共4页
Chinese Journal of Clinical Oncology and Rehabilitation
关键词
鼻咽肿瘤
放射性损伤
颞叶
弥散
定量研究
Nasopharyngeal neoplasms
Radiation injury
Temporal lobe
Diffusion
Quantitative study
