报告题目：Radioluminescence Imaging Based Spatiotemporal dosimetry and oximetry for FLASH radiotherapy
报 告 人：张荣晓
报告时间：2021年1月20日9:30-11:30
报告地点：腾讯会议925 189 211
主办单位：校科协、材料科学与技术学院
报告人简介：
张荣晓，美国达特茅斯学院副研究员。2015年博士毕业于美国达特茅斯学院，2015-2018年在哈佛大学完成住院医学物理师培训。2018年，埃默里大学质子中心担任助理教授、医学物理师，2020年至今在达特茅斯学院副研究员、临床物理师。主要从事基于光学的剂量测量与质量保证、蒙特卡罗模拟、人工智能在医学图像中的应用、光动力治疗等研究，致力于开展临床科学研究不断提升放射治疗疗效。目前已发表80余篇国际学术会议论文/摘要，60余篇学术期刊论文。
报告摘要：
Radiation therapy is anessential component of cancer care and over 14 million people a year, which is50% – 60% of total cancer patients. The capabilities available for cliniciansto localize and deliver precise amounts of radiation to specific anatomies haveimproved dramatically over recent years, due to advances in imaging guidance,treatment planning and dose delivery technologies. However, we are now facing along-lasting bottleneck to further improve the therapeutic ratio, i.e. tumorcontrol vs. normal tissue toxicity. Recent advances in ultra-high doseradiotherapy, abbreviated as FLASH, have shown the potential for reduction inhealthy tissue damage while preserving tumor control. FLASH therapy relies on very highdose rate of > 40Gy/sec with sub-second temporal beam modulation, taking aseemingly opposite direction from the conventional paradigm of fractionatedtherapy. With this, FLASH brings unique challenges to its dosimetry. Whilespatial dose conformity delivered to a target volume has been pushed to itspractical limits with advanced treatment planning and delivery, FLASH RTnecessitates novel spatiotemporal dosimetry techniques. The FLASH effect hasbeen reported mainly based upon phenomenological observations with tissuefunction assays, rather than mechanistic in situ measurements. There areseveral radiobiological hypotheses around the mechanisms for less damage, howeverto date none are directly proven, and indeed the data supporting any mechanismis glaringly absent. The central feature dominating most proposed mechanisms islinked to the fact that oxygen depletion, which is expected to occur rapidly atFLASH dose rates, via oxygen radical production with consumption from oxidationreactions.
