Abstract：Objective To verify the effectiveness of application of six-point marking in improvement of placement accuracy for pelvic cancers in contrast with traditional three-point marking methodology. Methods Altogether 60 pelvic cancer patients were randomly and evenly divided into two groups: Three-Point Marking Group (30 cases) and Six-Point Marking Group (30 cases), which adopted the traditional three-point and new six-point marking methodology respectively for placement. With application of accelerators, the radiation field verification films were taken pre-operatively by EPID (Electronic Portal Imaging Device) for each group and compared with BEV (Beam-field Equation Vision) films generated by the planning system. The placement errors in directions of X (left and right), Y (head and feet) and Z (abdomen and back) were calculated. Results No statistically significant differences were seen in placement errors in the direction of Z between Three-Point Marking Group and Six-Point Marking Group (P>0.05), indicating that six-point marking methodology could not reduce the placement errors in the direction of back and abdomen. While, statistically significant differences existed in placement errors in the direction of X and Y between two groups (both P<0.05), indicating that six-point marking methodology could reduce the placement errors in the direction of the left side, right side, head and feet. Conclusion Six-point marking methodology demonstrated its easy-to-operate features in remarkable improvement of the accuracy of radiotherapy placement for pelvic cancers, which deserved wider clinical promotion.
李鹏，李长龙，张明涛，周鸣飞，黄衍兵，邱亮. 六点标记法对提高盆腔肿瘤摆位精度的临床价值[J]. 中国医疗设备, 2015, 30(8): 116-119.
LI Peng, LI Chang-long, ZHANG Ming-tao, ZHOU Ming-fei, HUANG Yan-bing, QIU Liang. Clinical Effectiveness of Application of Six-Point Marking in Improvement of Placement Accuracy for Pelvic Cancers. China Medical Devices, 2015, 30(8): 116-119.
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