Treatment Planning using Physiologic MRI Data

该应用程序要求支持将生理磁共振成像（MRI）方法整合到 更好地描述和描述多形性胶质母细胞瘤（GBM）脑肿瘤，为放射治疗做准备 我们假设使用这些成像方法将导致更精确的治疗。 放射治疗计划。拟议的研究是基于广泛的初步数据 表明化学位移成像（CSI）、灌注和扩散成像以及基于MR的缺氧标测增加了 关于肿瘤生理学的附加信息，其可以被并入治疗计划，目标是 降低肿瘤复发率。虽然T2 MRI上的异常区域与 显微镜下可见肿瘤扩散，部分异常表现为水肿，无恶性细胞， 其它区域可能含有高浓度的恶性细胞， 治疗加强量。虽然大多数恶性脑肿瘤在放射治疗区域内复发，但20- 25%的复发发生在这些领域之外。因此，我们预计至少有25%的患者 将存在> 10%的增压体积差异。我们预计，至少有一些外地， 通过使用成像技术可以预测复发。因此，成像技术将是 用于识别每个肿瘤内的“高风险子体积”，这些子体积可能具有高复发风险。后 完成放疗后，患者将接受系列生理MRI扫描;研究终点为 第一次复发。具体目标是： 1)使用血氧水平依赖（BOLD）MRI创建单个肿瘤内的缺氧图 再加上碳源呼吸 2)使用化学位移成像（CSI）探测肿瘤的增殖潜力。 3)使用对比增强灌注MRI评估肿瘤的血管生成特征。 4)使用弥散加权MRI评估肿瘤的细胞构成。 5)比较AIMS 1-4中创建的地图的位置和区域。 6)从AIM 5定义的区域生成临床靶体积（CTV）。

This application requests support to integrate physiologic magnetic resonance imaging (MRI) methods to better describe and delineate glioblastoma multiforme (GBM) brain tumors in preparation for radiation therapy treatment.We hypothesize that the use of these imaging methods will result in more precise radiotherapy treatment planning. The proposed research is based upon extensive preliminary data indicating chemical shift imaging (CSI), perfusion and diffusion imaging and MR-based hypoxia mapping add additional information about tumor physiology that can be incorporated into a treatment plan with the goal of decreasing the rate of tumor recurrence. Although regions of abnormality on T2 MRI are known to correlate with microscopic spread of tumor, some of this abnormality represents edema without malignant cells while other areas may contain a high concentration of malignant cells that should be incorporated into the treatment boost volume. While most malignant brain tumors recur within the radiation treatment fields, 20- 25% of recurrencesoccur outside of these fields. For this reason, we expect that in at least 25% of patients there will be a boost volume discrepancy > 10%. We anticipate that at least some of these out-of-field recurrences could be predicted by the use of the imaging techniques. Thus, the imaging techniques will be used to identify "high-risk subvolumes" within each tumor, which may be at high risk of recurrence. After completing radiotherapy, patients will be followed with serial physiologic MRI scans; the study endpoint being the first recurrence.The SPECIFIC AIMS are: 1) Create maps of hypoxia within individual tumors using blood oxygen level dependent (BOLD) MRI combined with carbogen breathing. 2) Probe the proliferative potential of tumors using chemical-shift imaging (CSI). 3) Assess the angiogenic features of a tumor using contrast enhanced perfusion MRI. 4) Assess the cellularity of a tumor using diffusion-weighted MRI. 5) Compare the locations and areas of maps created in AIMS 1-4. 6) Generate clinical target volumes (CTV's) from the regions defined by AIM 5.