School of Physics, University of Galway, Galway, Ireland.
Department of Medical Physics, Blackrock Health Galway Clinic, Galway, Ireland.
J Appl Clin Med Phys. 2023 Jun;24(6):e13932. doi: 10.1002/acm2.13932. Epub 2023 Feb 16.
ICRU 91, published in 2017, is an international standard for prescribing, recording, and reporting stereotactic treatments. Since its release, there has been limited research published on the implementation and impact of ICRU 91 on clinical practice. This work provides an assessment of the recommended ICRU 91 dose reporting metrics for their use in clinical treatment planning. A set of 180 intracranial stereotactic treatment plans for patients treated by the CyberKnife (CK) system were analyzed retrospectively using the ICRU 91 reporting metrics. The 180 plans comprised 60 trigeminal neuralgia (TGN), 60 meningioma (MEN), and 60 acoustic neuroma (AN) cases. The reporting metrics included the planning target volume (PTV) near-minimum dose ( ), near-maximum dose ( ), and median dose ( ), as well as the gradient index (GI) and conformity index (CI). The metrics were assessed for statistical correlation with several treatment plan parameters. In the TGN plan group, owing to the small targets, was greater than in 42 plans, whereas both metrics were not applicable in 17 plans. The metric was predominantly influenced by the prescription isodose line (PIDL). The GI was significantly dependent on target volume in all analyses performed, where the variables were inversely related. The CI was only dependent on target volume in treatment plans for small targets. The ICRU 91 and metrics breakdown in plans for small target volumes below 1 cm ; the Min and Max pixel should be reported in such cases. The metric is of limited use for treatment planning. Given their volume dependence, the GI and CI metrics could potentially serve as plan evaluation tools in the planning of the sites analyzed in this study, which would ultimately improve treatment plan quality.
ICRU91 于 2017 年发布，是规定、记录和报告立体定向治疗的国际标准。自发布以来，关于 ICRU91 在临床实践中的实施和影响的研究有限。这项工作评估了推荐的 ICRU91 剂量报告指标，以将其用于临床治疗计划。使用 ICRU91 报告指标对使用 CyberKnife（CK）系统治疗的 180 例颅内立体定向治疗计划进行了回顾性分析。这 180 个计划包括 60 例三叉神经痛（TGN）、60 例脑膜瘤（MEN）和 60 例听神经瘤（AN）病例。报告指标包括计划靶区（PTV）最小近点剂量（ ）、最大近点剂量（ ）和中位数剂量（ ），以及梯度指数（GI）和适形指数（CI）。评估了这些指标与多个治疗计划参数的统计学相关性。在 TGN 计划组中，由于靶区较小，有 42 个计划的 大于 ，而 17 个计划这两个指标均不适用。 指标主要受处方等剂量线（PIDL）的影响。GI 在所有分析中均显著依赖于靶区体积，其中变量呈反比关系。CI 仅在针对小靶区的治疗计划中依赖于靶区体积。在靶区体积小于 1cm 3 的小靶区计划中，ICRU91 和 指标存在差异；在这种情况下，应该报告最小和最大像素。 指标对于治疗计划的用处有限。鉴于它们的体积依赖性，GI 和 CI 指标可能成为本研究分析的部位的计划评估工具，这将最终提高治疗计划质量。
