University of Kentucky.
J Appl Clin Med Phys. 2013 Sep 6;14(5):104-14. doi: 10.1120/jacmp.v14i5.4304.
The feasibility of delivering craniospinal irradiation (CSI) with TomoDirect is investigated. A method is proposed to generate TomoDirect plans using standard three-dimensional (3D) beam arrangements on Tomotherapy with junctioning of these fields to minimize hot or cold spots at the cranial/spinal junction. These plans are evaluated and compared to a helical Tomotherapy and a three-dimensional conformal therapy (3D CRT) plan delivered on a conventional linear accelerator (linac) for CSI. The comparison shows that a TomoDirect plan with an overlap between the cranial and spinal fields might be preferable over Tomotherapy plans because of decreased low dose to large volumes of normal tissues outside of the planning target volume (PTV). Although the TomoDirect plans were not dosimetrically superior to a 3D CRT linac plan, the patient can be easily treated in the supine position, which is often more comfortable and efficient from an anesthesia standpoint. TomoDirect plans also have only one setup position which obviates the need for matching of fields and feathering of junctions, two issues encountered with conventional 3D CRT plans. TomoDirect plans can be delivered with comparable treatment times to conventional 3D plans and in shorter times than a Tomotherapy plan. In this paper, a method is proposed for creating TomoDirect craniospinal plans, and the dosimetric consequences for choosing different planning parameters are discussed.
研究了使用 TomoDirect 进行颅脊髓照射（CSI）的可行性。提出了一种方法，即在 Tomotherapy 上使用标准的三维（3D）射束排列生成 TomoDirect 计划，并将这些射束连接起来，以最大限度地减少颅/脊髓交界处的热点或冷点。评估了这些计划，并与螺旋 Tomotherapy 和在常规线性加速器（linac）上进行的三维适形治疗（3D CRT）计划进行了比较。比较结果表明，由于颅部和脊髓部之间重叠的 TomoDirect 计划可能会降低计划靶区（PTV）外大体积正常组织的低剂量，因此优于 Tomotherapy 计划。尽管 TomoDirect 计划在剂量学上并不优于 3D CRT linac 计划，但患者可以在仰卧位接受治疗，从麻醉角度来看，这种体位通常更舒适和高效。TomoDirect 计划也只有一个设置位置，避免了常规 3D CRT 计划中遇到的场匹配和交界羽化问题。TomoDirect 计划的治疗时间与常规 3D 计划相当，比 Tomotherapy 计划短。在本文中，提出了一种创建 TomoDirect 颅脊髓计划的方法，并讨论了选择不同计划参数的剂量学后果。
