Treatment planning of intracranial targets on MRI derived substitute CT data
Treatment planning of intracranial targets on MRI derived substitute CT data
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DOI：
10.1016/j.radonc.2013.04.028
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发表时间：
2013-07-01
影响因子：
5.7
通讯作者：
Nyholm, Tufve
中科院分区：
文献类型：
--
作者：
Jonsson, Joakim H.;Johansson, Adam;Nyholm, Tufve
背景资料：磁共振成像（MRI）作为计算机断层扫描（CT）的补充，在放射治疗的目标定义程序的使用正在增加。为了消除由于图像配准引起的系统不确定性，完全基于MRI的工作流程可能是优选的。在目前的试点研究中，我们调查的剂量计算精度自动生成的替代CT（S-CT）图像的头部MRI的基础上。我们还产生数字重建X线片（DRR）从S-CT数据，以评估患者定位的可行性MR images.Methods和材料的基础上：5例患者被纳入本研究。对未经不均匀性校正的CT、s-CT、s-CT数据和体密度指定的MRI图像进行剂量计算。使用点剂量和剂量体积直方图（DVH）的比较，和伽马指数evaluation.Results：结果表明，S-CT图像提高剂量计算的准确性相比，非均匀性校正的剂量计算的方法（平均改善2.0%点），它执行几乎相同的堆密度分配的方法。的S-CT为基础的DRR似乎是足够的病人定位颅内目标，虽然需要进一步调查，在这个subject.Conclusion：的S-CT方法是非常快的，并产生的数据，可用于治疗计划，而不会牺牲准确性。(C)2013爱思唯尔爱尔兰有限公司版权所有。
Background: The use of magnetic resonance imaging (MRI) as a complement to computed tomography (CT) in the target definition procedure for radiotherapy is increasing. To eliminate systematic uncertainties due to image registration, a workflow based entirely on MRI may be preferable. In the present pilot study, we investigate dose calculation accuracy for automatically generated substitute CT (s-CT) images of the head based on MRI. We also produce digitally reconstructed radiographs (DRRs) from s-CT data to evaluate the feasibility of patient positioning based on MR images.Methods and materials: Five patients were included in the study. The dose calculation was performed on CT, s-CT, s-CT data without inhomogeneity correction and bulk density assigned MRI images. Evaluation of the results was performed using point dose and dose volume histogram (DVH) comparisons, and gamma index evaluation.Results: The results demonstrate that the s-CT images improve the dose calculation accuracy compared to the method of non-inhomogeneity corrected dose calculations (mean improvement 2.0% points) and that it performs almost identically to the method of bulk density assignment. The s-CT based DRRs appear to be adequate for patient positioning of intra-cranial targets, although further investigation is needed on this subject.Conclusion: The s-CT method is very fast and yields data that can be used for treatment planning without sacrificing accuracy. (C) 2013 Elsevier Ireland Ltd. All rights reserved.