宫颈癌危及器官MIM-Maestro和RayStation软件自动勾画优势对比研究

Comparative study of two software tools on the atlas-based auto-segmentation of organs-at-risk in cervical cancer

目的放射治疗过程中危及器官的勾画繁琐耗时,自动勾画软件的出现在一定程度上提高了勾画效率。本研究探讨基于Atlas实施宫颈癌危及器官自动勾画时不同软件对自动勾画结果的影响。方法分别基于MIM-Maestro6.6.5和RayStation 6.0软件建立入库病例数目为60例的宫颈癌Atlas模板库,该60例患者由中国人民解放军总医院放射治疗科2014-07-01-2016-12-31收治,随机选择Atlas库外10例宫颈癌患者,由中国人民解放军总医院放射治疗科2017-01-01-2017-04-30收治,临床医生手动勾画危及器官(膀胱、直肠和双侧股骨头),并定义为参考勾画(Vref)。分别运用2款软件对10例患者的CT图像进行自动勾画。采用勾画时间(T)、相似性系数(dice similarity coefficient,DSC)、敏感性指数(sensitivity index,SI)、包容性系数(inclusiveness index,IncI)、质心偏差(deviation of centroid,DC)、Jaccard系数(jaccard index,JAC)、Hausdorff距离(hausdorff distance,HD)评价勾画结果,并进行配对样本t检验。结果MIM软件的勾画时间为(1.89±0.09)min,小于RayStation软件的勾画时间(8.17±0.63)min,Z=-2.81,P=0.01。膀胱的勾画结果显示,除HD〔(2.92±1.17)cmvs(3.68±1.51)cm,Z=-1.07,P=0.29〕外均差异有统计学意义,MIM软件勾画结果优于RayStation软件。对于直肠,2款软件勾画结果的各评价参数差异均无统计学意义,均P>0.05;从均值分析,MIM软件的结果在体积(DSC:0.53±0.08;JAC:0.37±0.08)上优于RayStation软件(DSC:0.48±0.18;JAC:0.34±0.16),但在位置上MIM软件〔DC:(1.58±0.75)cm;HD:(3.54±0.89)cm〕略差于RayStation软件〔DC:(1.56±0.52)cm;HD:(3.40±1.0)cm〕。对于双侧股骨头,2款软件的勾画结果差异均无统计学意义,勾画结果均较为理想(DSC左侧股骨头0.86±0.04 vs 0.86±0.05,Z=-0.12,P>0.05;DSC右侧股骨头0.85±0.03 vs 0.85±0.04,Z=0.36,P>0.05)。结论基于Atlas实施危及器官自动勾画时,MIM软件勾画效率高于RayStation软件。2款软件对于双侧股骨头的勾画结果处于较好水平,但对于直肠的勾画结果都不理想,在膀胱的勾画中MIM软件优于RayStation软件。

OBJECTIVE The contouring of organs during radiotherapy is time-consuming,the emergence of autosegmentation software improves the efficiency of delineation to some extent.The aim of this study was to evaluate the effect of two software tools on the atlas-based auto-segmentation of organs-at-risk in cervical cancer.METHODS The atlas of cervical cancer(the cases were 60)was established in MIM-Maestro 6.6.5 and Ray Station 6.0 respectively,these cases of cervical cancer were collected in department of radiotherapy of PLA General Hospital from 2014-07-01 to2016-12-31.Another 10 patients of cervical cancer were randomly selected out of the atlas which were also collected in department of radiotherapy of PLA General Hospital from 2017-01-01 to 2017-4-30.An experienced radiation oncologist contoured 4 OARs(bladder,rectum and femoral heads)based on the published guidelines which were defined as the reference volumes(Vref).The OARs were auto-contoured by two sets of software respectively.The similarity of the ABAS and reference contours were assessed using dice similarity coefficient(DSC),sensitivity index(SI),inclusiveness index(IncI),deviation of centroid(DC),jaccard coefficient(JAC)and hausdorff distance(HD).The time for manual and auto-contouring were also recorded.The results were statistically evaluated using paired t-test.RESULTS The delineated time of MIM was significantly less than that of RayStation[(1.89±0.09)min vs(8.17±0.63)min,Z=-2.81,P<0.001].The results of bladder contouring in MIM showed better than those in RayStation except the value of HD[(2.92±1.17)cmvs(3.68±1.51)cm,Z=-1.07,P=0.29]significantly(P<0.05).For the rectum,there were no significant differences in the analysis parameters of two tools,but MIM had the advantage in volume[VMIM vs VRS:0.53±0.08 vs 0.48±0.18(DSC);0.37±0.08 vs 0.34±0.16(JAC)]instead of in position[VMIMvs VRS:(1.58±0.75)cmvs(1.56±0.52)cm(DC);(3.54±0.89)cmvs(3.40±1.00)cm(HD)]for the analysis of mean values.For the bilateral femoral heads,the contouring results were both well and there was no significant difference between two sets of software[DSC:0.86±0.04 vs 0.86±0.05,Z=-0.12(left femoral head);0.85±0.03 vs 0.85±0.04,Z=0.36(right femoral head);both P>0.05].CONCLUSIONS MIM is higher in efficiency than RayStation for processing atlas-based auto-segmentation.The auto-contouring in two sets of software for bilateral femoral heads are kept at the good level,except for the rectum.In addition,MIM is superior to RayStation in the delineation of bladder.