提高肺SBRT精度的多窗位动态组合诊疗手段

Multi-window Dynamic Combination Diagnosis and Treatment Method to Improve the Accuracy of Lung Stereotactic Radiotherapy

目的研究不同窗位描绘肿瘤真实范围的能力以寻找最佳窗位组合。方法本研究提出三个指标(目标肿瘤可偏移空间、目标肿瘤体积一致性,目标肿瘤图像置信度)对115例肺立体定向放射治疗患者的MVCT图像进行评估。结果对于存在边缘晕征的肿瘤,调整窗位可以获得目标肿瘤更真实的范围,窗位值达到-612HU效果最佳;对于局部密度变化单一边缘清晰的病灶,窗位的调整带来的图像引导精度提高不明显;对于存在瘤周弥漫性炎症的病灶,窗位调整不适用,无法提高图像引导精度。结论多窗位动态组合可以获取更真实的肿瘤范围,有助于降低图像引导误差,提高肺立体定向放射治疗精度。

Objective Study the ability of different window levels to delineate the true range of tumors to find the optimal combination of window levels.Methods three metrics(target tumor deflectable space,target tumor volume consistency,target tumor image confidence)were proposed to evaluate the MVCT images of 115 patients with lung stereotactic radiosurgery.Results For tumors where the rim halo sign is present,adjusting the window levels can obtain a more realistic range of the target tumor,and the window levels value reaches-612HU with the best effect.For lesions with a single edge with a clear edge of local density change,the image guidance accuracy brought by the adjustment of window levels is not significantly improved.For lesions with peritumoral diffuse inflammation,window levels adjustment is not applicable and cannot improve image guidance accuracy.Conclusion Multi-window dynamic combination can obtain a more realistic tumor range,which is helpful to reduce image guidance error and improve the accuracy of lung stereotactic radiotherapy.