Abstract：Objective To explore the effect of calculating grid size on cervical cancer case optimization when using volumetric
modulated arc therapy (VMAT) plan in Monaco planning system. Methods CT images of 15 cervical patients who received
radiotherapy in our hospital in Monaco system were selected, and the plan was optimized using the rotational treatment method of
VMAT in Monaco planning system. The planned results were obtained by only changing the grid size (2, 3, 4, 5, 6, 7, 8 mm) in the
planning design parameters. The target area and organs at risk were analyzed. Results Using 2 mm calculation grid size as reference,
the D98, Dmean, D2 and homogeneity index (HI) of PTV were statistically significant differences when the calculation grid was 3 mm
(P<0.05). As the calculation grid increased, the difference of Dmean, D2 and HI were still statistically significant (P<0.05). When the
calculation grid increased to 5 mm, for organs at risk, there was significant difference between the V40 of the small intestine and the
V30 and V40 of the colon (P<0.05). When the calculation grid was 4 mm, the V45 of the bladder had significant difference (P<0.05).
When the calculation grid was 8 mm, the left femoral head was significantly difference (P<0.05). Conclusion In Monaco planning
system, the mesh size of 3 mm is an appropriate choice for cervical cancer patients, which can provide a certain reference for the
design of clinical planning. This will not only improve the efficiency of treatment, but also satisfy the therapeutic effect.
魏敏，陈长建，葛双，郗会珍，程锦绣，魏鹏，朱培军，叶书成. VMAT计划中计算网格尺寸对宫颈癌放疗剂量的影响[J]. 中国医疗设备, 2022, 37(11): 43-46.
WEI Min, CHEN Changjian, GE Shuang, XI Huizhen, CHENG Jinxiu, WEI Peng, ZHU Peijun, YE Shucheng. Effect of Calculation Grid Size on Radiotherapy Dose of Cervical Cancer in VMAT Planning. China Medical Devices, 2022, 37(11): 43-46.
