Cone-beam CT based image-guidance for extracranial stereotactic radiotherapy of intrapulmonary tumors
Cone-beam CT based image-guidance for extracranial stereotactic radiotherapy of intrapulmonary tumors
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DOI：
10.1080/02841860600904839
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发表时间：
2006-09-01
期刊：
影响因子：
3.1
通讯作者：
Flentje, Michael
中科院分区：
文献类型：
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作者：
Guckenberger, Matthias;Meyer, Juergen;Flentje, Michael
对基于锥形束CT（CB - CT）的图像引导在肺内肿瘤的颅外立体定向放射治疗中的应用进行了评估。共有21例患者（25个病灶：原发性非小细胞肺癌6例；肺转移瘤19例）接受了立体定向放射治疗（1到8个分次）。在每次分次治疗前，在治疗位置获取CB - CT，测量并校正计划肿瘤位置与实际肿瘤位置之间的误差。研究了手动评估肿瘤位置误差的观察者内和观察者间变异性，并将这种手动方法与自动图像配准进行了比较。基于66次分次的CB - CT，计划肿瘤位置与实际肿瘤位置之间的差异（三维矢量）为7.7毫米±1.3毫米。相对于骨性解剖结构的肿瘤位置误差为5.3毫米±1.2毫米，骨性解剖结构与肿瘤位置之间的相关性较差。手动评估肿瘤位置误差的观察者内和观察者间变异性分别为0.9毫米±0.8毫米和2.3毫米±1.1毫米。自动图像配准显示出高度可重复性的结果（<1毫米）。然而，与手动配准相比，在主要的肿瘤呼吸运动方向上发现了一个系统误差（2.5毫米对1.4毫米）。使用CB - CT的图像引导在肺内肿瘤的高精度放射治疗中得到了验证。结果表明，计划参考和验证图像研究都必须考虑肿瘤的呼吸运动。
Cone-beam CT ( CB-CT) based image-guidance was evaluated for extracranial stereotactic radiotherapy of intrapulmonary tumors. A total of 21 patients (25 lesions: prim. NSCLC n = 6; pulmonary metastases n = 19) were treated with stereotactic radiotherapy (1 to 8 fractions). Prior to every fraction a CB-CT was acquired in treatment position, errors between planned and actual tumor position were measured and corrected. Intra- and inter-observer variability of manual evaluation of tumor position error was investigated and this manual method was compared with automatic image registration. Based on CB-CTs from 66 fractions the discrepancy (3-D vector) between planned and actual tumor position was 7.7 mm +/- 1.3 mm. Tumor position error relative to the bony anatomy was 5.3 mm +/- 1.2 mm, the correlation between bony anatomy and tumor position was poor. Intra- observer and inter-observer variability of manual evaluation of tumor position error was 0.9 mm +/- 0.8 mm and 2.3 mm +/- 1.1 mm, respectively. Automatic image registration showed highly reproducible results (< 1 mm). However, compared with manual registration a systematic error was found in direction of predominant tumor breathing motion (2.5 mm vs 1.4 mm). Image-guidance using CB-CT was validated for high precision radiotherapy of intrapulmonary tumors. It was shown that both the planning reference and the verification image study have to consider tumor breathing motion.