基于锥形束计算机断层扫描的合成计算机断层扫描在笔形束扫描质子治疗自适应评估中的应用与陷阱

The Applications and Pitfalls of Cone-Beam Computed Tomography-Based Synthetic Computed Tomography for Adaptive Evaluation in Pencil-Beam Scanning Proton Therapy.

作者信息

Tsai Pingfang, Tseng Yu-Lun, Shen Brian, Ackerman Christopher, Zhai Huifang A, Yu Francis, Simone Charles B, Choi J Isabelle, Lee Nancy Y, Kabarriti Rafi, Lazarev Stanislav, Johnson Casey L, Liu Jiayi, Chen Chin-Cheng, Lin Haibo

机构信息

New York Proton Center, New York, NY 10035, USA.

Proton Center, Taipei Medical University, Taipei 11031, Taiwan.

出版信息

Cancers (Basel). 2023 Oct 22;15(20):5101. doi: 10.3390/cancers15205101.

DOI:10.3390/cancers15205101

PMID:37894469

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10605451/

Abstract

PURPOSE

The study evaluates the efficacy of cone-beam computed tomography (CBCT)-based synthetic CTs (sCT) as a potential alternative to verification CT (vCT) for enhanced treatment monitoring and early adaptation in proton therapy.

METHODS

Seven common treatment sites were studied. Two sets of sCT per case were generated: direct-deformed (DD) sCT and image-correction (IC) sCT. The image qualities and dosimetric impact of the sCT were compared to the same-day vCT.

RESULTS

The sCT agreed with vCT in regions of homogeneous tissues such as the brain and breast; however, notable discrepancies were observed in the thorax and abdomen. The sCT outliers existed for DD sCT when there was an anatomy change and for IC sCT in low-density regions. The target coverage exhibited less than a 5% variance in most DD and IC sCT cases when compared to vCT. The D of serial organ-at-risk (OAR) in sCT plans shows greater deviation from vCT than small-volume dose metrics (D0.1cc). The parallel OAR volumetric and mean doses remained consistent, with average deviations below 1.5%.

CONCLUSION

The use of sCT enables precise treatment and prompt early adaptation for proton therapy. The quality assurance of sCT is mandatory in the early stage of clinical implementation.

摘要

目的

本研究评估基于锥形束计算机断层扫描（CBCT）的合成CT（sCT）作为验证CT（vCT）的潜在替代方法，用于在质子治疗中加强治疗监测和早期适应性调整的效果。

方法

研究了七个常见的治疗部位。每个病例生成两组sCT：直接变形（DD）sCT和图像校正（IC）sCT。将sCT的图像质量和剂量学影响与同日的vCT进行比较。

结果

sCT在脑和乳腺等均匀组织区域与vCT一致；然而，在胸部和腹部观察到明显差异。当解剖结构发生变化时，DD sCT存在sCT异常值，而在低密度区域IC sCT存在异常值。与vCT相比，大多数DD和IC sCT病例中靶区覆盖的差异小于5%。sCT计划中系列危及器官（OAR）的剂量与vCT相比，显示出比小体积剂量指标（D0.1cc）更大的偏差。并行OAR的体积和平均剂量保持一致，平均偏差低于1.5%。