目的 应用SPECT肺灌注检查,探讨放疗计划功能剂量学参数与放射性肺损伤之间的关系,并探索运用SPECT优化放疗计划的优势.方法 2014—2015年入组23例NSCLC患者,全部患者放疗前行SPECT肺灌注检查,生成功能剂量体积直方图fDVH,对比fVx(接受≥xGy照射功能肺组织占全部功能肺组织体积百分比)与RP发生的相关性.优化放疗计划,对比优化后放疗计划与常规放疗计划中的剂量学参数.采用χ2检验、ROC曲线分析应用,常规放疗计划的DVH及fDVH参数与回顾性优化后放疗计划DVH参数采用配对t检验.结果 双肺fV13与≥2级RP发生率相关性最高.优化放疗方案后fV10、fV13、f V20、fV25、fV40明显降低(P=0006、0007、0010、0036、0035),CI较原放疗方案增加(P=0040).结论 SPECT可优化放疗计划,fV13可能与RP发生率和程度有关.%Objective To explore the relationship between functional dosimetric parameters of radiotherapy plans and radiation?induced lung injury using single?photon emission computed tomography ( SPECT) perfusion lung scintigraphy, and to investigate the advantages of SPECT in optimizing radiotherapy plans. Methods From 2014 to 2015, 23 patients with non?small cell lung cancer ( NSCLC) who received SPECT perfusion lung scintigraphy before radiotherapy were enrolled as subjects. The functional dose?volume histogram ( fDVH) was generated and the relationship between fVx ( the volume proportion of the functional lung tissue exposed to ≥x Gy of radiation in the whole functional lung tissue ) and radiation?induced pneumonitis (RP) was explored. The radiotherapy plans were optimized based on SPECT and the dosimetric parameters were then compared between the optimized and conventional radiotherapy plans. The SPSS 13 software was used for chi?square test and receiver operating characteristic curve analysis. Comparison of DVH and fDVH between conventional and optimized radiotherapy plans was made by paired t test. Results The fV13 value for both lungs was most correlated with the incidence of grade ≥2 RP. The fV10, fV13, f V20, fV25 , and fV40 values were significantly reduced and the conformity index was significantly improved after optimization ( P= 0006, 0007, 0010, 0036, 0035, 0040 ) . Conclusions SPECT can be used to optimize radiotherapy plans. The fV13 value may be correlated with the incidence and severity of RP.
展开▼
