肺内孤立灶大体肿瘤体积CT不同扫描方式比较

A comparison of the different CT scanning modes on the GTV delineation of the solitary pulmonarylesion

目的比较cT不同扫描方式对肺内孤立病灶大体肿瘤体积（GTV）勾画影响，探讨螺旋扫描在CT模拟定位中的可行性。方法对16例周围型或转移性肺癌分别行轴位（A）、螺旋（S）CT扫描，比较GTV A、GTV S大小和位置差异（配对t检验），计算GTVA、GTV。匹配指数（MI）及与体积相关性（两变量相关分析）。结果GTV A 、GTV S大小分别为8．95、9．38cm^3（t=0．43，P=0．667）。GTVA、GTV。等中心点坐标值x轴分别为6．80、6．81cm（t=0．27，P=0．794），Y轴分别为36．19、36．05cm（t=0．37，P=0．717），z轴分别为4．99、4．96cm（t=0．65，P=0．526）。GTVA和GTV。等中心点至坐标原点距离相似（38．31am：38．23cm，t=0．47，P=0．646）。GTVA与GTV3的MI为0．36（0～0．77），MI与体积显著相关（r=0．587，P=0．017）。结论轴位与螺旋CT扫描方式确定肺内孤立灶GTV的MI与其有相关性，螺旋扫描速度更快，在肺内孤立灶CT模拟定位中具有可行性。

Objective To explore the influence of the CT scanning mode on the gross tumor volume （GTV） delineation of solitary pulmonary lesion （SPL） , and to evaluate the feasibility of the spiral CT scan in CT simulation. Methods Sixteen patients with SPL underwent axial scan, spiral scan during free breathing. Compare the target position, volume between GTV. and GTVA （paired t-test）. The matching index （MI） between GTVs and GTVA and correlations between MI and the tumor volume were calculated （ bivariate correlation analysis）. Results GTV. and GTVA volume was 8. 95 em3 and 9. 38 cm^3 （ t = 0.43, P =0. 667） , respectively. The eentroid position for GTVs and GTVA in x,y and z axises were 6. 80 cm and 6. 81 em （t =0. 27,P =0.794）, 36. 19 cm and 36.05 cm （t =0. 37,P =0.717） , and 4. 99 cm and 4. 96 cm （ t = 0. 65, P = 0. 526 ） , respectively. There were also no statistically significant difference in the distance between the centroidal position and origin of coordinates for GTV. and GTVA （38.31 em： 38. 23 cm, t = 0. 47 ,P = 0. 646）. MI between GTVs and GTVA was 0. 36 （range 0 -0. 77 ）, correlated with the tumor volume （ r = 0. 587, P = 0. 017 ）. Conclusions There was no significant difference between the axial scan and spiral scan in the GTV volume and position for SPL, but MI between GTV. and GTVa were small. A correlation was found for the MI between GTV. and GTVA with the tumor volume. Spiral CT scan was more timesaving, and was feasible in CT simulation scan.