DOSIMETRIC IMPACT OF ONLINE CORRECTION VIA CONE-BEAM CT-BASED IMAGE GUIDANCE FOR STEREOTACTIC LUNG RADIOTHERAPY
DOSIMETRIC IMPACT OF ONLINE CORRECTION VIA CONE-BEAM CT-BASED IMAGE GUIDANCE FOR STEREOTACTIC LUNG RADIOTHERAPY
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DOI：
10.1016/j.ijrobp.2010.02.012
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发表时间：
2010-12-01
影响因子：
7
通讯作者：
Yan, Di
中科院分区：
文献类型：
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作者：
Galerani, Ana Paula;Grills, Inga;Yan, Di
目的评价在线锥束计算机断层扫描(CBCT)引导下肺立体定向全身放射治疗(SBRT)的剂量学影响。方法与材料分析2 0例接受肺立体定向全身放射治疗(SBRT)患者的2 0张计划图像和162张CBCT图像。将校正前CBCT(患者就诊后，不校正)注册为软组织计划CT，床位移位，第二次CBCT用于验证(校正后CBCT)靶点和正常结构在CBCT的大体肿瘤体积(GTV)、临床靶区体积(CTV)、索道、食道、肺、近端支气管树、结果在CBCT引导下，GTV D-99%、GTV D-95%、CTV D-99%和CTV D-95%的靶区剂量相对于治疗计划的平均值和标准差分别为-3.2%(49%)、-2.1%(4.4%)、-6.1%(10.7%)和-3.5%(7%)，正常器官最大剂量差值校正前为2.2%(6.5%)，矫治后为2.4%(59%)，脐带6.1%(14.1%)和3.8%(8.1%)，近端支气管树3.1%(17.5%)和6.2%(9.8%)。结论CBCT在线引导提高了肺SBRT靶区剂量投放的准确性，但无论校正与否，正常组织的治疗剂量可能不同，靶区配准时应考虑正常组织。
Purpose To evaluate the dosimetric Impact of online cone-beam computed tomography (CBCT) guided correction in lung stereotactic body radiation therapy (SBRT)Methods and Materials Twenty planning and 162 CBCT images from 20 patients undergoing lung SBRT were analyzed The precorrection CBCT (CBCT after patient setup, no couch correction) was registered to planning CT using soft tissue, couch shift was applied, with a second CBCT for verification (postcorrection CBCT) Targets and normal structures were delineated on CBCTs gross tumor volume (GTV), clinical target volume (CTV), cord, esophagus, lung, proximal bronchial tree, and aorta Dose distributions on all organs manifested on each CBCT were compared with those planned on the CTResults Without CBCT guided target position correction, target dose reduced with respect to treatment plan Mean and standard deviation of treatment dose discrepancy from the plan were -3 2% (49%), -2 1% (4 4%), -6 1% (10 7%), and -3 5% (7%) for GTV D-99%, GTV D-95%, CTV D-99%, and CTV D-95%, respectively With CBCT correction, the results were -0 4% (2 6%), 0 1% (1 7%), -0 3% (4 2%), and 0 5% (3%) Mean and standard deviation of the difference in normal organ maximum dose were 2 2% (6 5%) before correction and 2 4% (59%) after correction for esophagus, 6 1% (14 1%) and 3 8% (8 1%) for cord, 3 1% (17 5 %) and 6 2% (9 8%) for proximal bronchial tree, and 17 7% (19 5%) and 14 1% (17%) for aortaConclusion Online CBCT guidance improves the accuracy of target dose delivery for lung SBRT However, treatment dose to normal tissue can vary regardless of the correction Normal tissues should be considered during target registration, according to target proximity (C) 2010 Elsevier Inc