报告题目：Radioluminescence Imaging Based Spatiotemporal dosimetry and oximetry for FLASH radiotherapy
报 告 人：张荣晓/副研究员
报告时间：2021年1月20日（周三）上午9:30-11:30
报告地点：腾讯会议 ID: 925 189 211
主办单位：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 an essential component of cancer care and over 14 million people a year, which is 50% – 60% of total cancer patients. The capabilities available for clinicians to localize and deliver precise amounts of radiation to specific anatomies have improved dramatically over recent years, due to advances in imaging guidance, treatment planning and dose delivery technologies. However, we are now facing a long-lasting bottleneck to further improve the therapeutic ratio, i.e. tumor control vs. normal tissue toxicity. Recent advances in ultra-high dose radiotherapy, abbreviated as FLASH, have shown the potential for reduction in healthy tissue damage while preserving tumor control.
FLASH therapy relies on very high dose rate of > 40Gy/sec with sub-second temporal beam modulation, taking a seemingly opposite direction from the conventional paradigm of fractionated therapy. With this, FLASH brings unique challenges to its dosimetry. While spatial dose conformity delivered to a target volume has been pushed to its practical limits with advanced treatment planning and delivery, FLASH RT necessitates novel spatiotemporal dosimetry techniques. The FLASH effect has been reported mainly based upon phenomenological observations with tissue function assays, rather than mechanistic in situ measurements. There are several radiobiological hypotheses around the mechanisms for less damage, however to date none are directly proven, and indeed the data supporting any mechanism is glaringly absent. The central feature dominating most proposed mechanisms is linked to the fact that oxygen depletion, which is expected to occur rapidly at FLASH dose rates, via oxygen radical production with consumption from oxidation reactions.
