用166Ho聚L-乳酸微球进行放射栓塞的剂量测量研究:死亡时间对预测功率的影响
Bartolomeo Cassano1, Ludovica Miseo2,3, Sara Ungania1
1Department of Research, Diagnosis and Innovative Technologies, Medical Physics Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy.
EJNMMI physics
|July 3, 2025
概括
死亡时间 (DT) 显著影响使用holmium-166 poly-L-乳酸 (Ho-PLLA) 微球进行放射性栓塞的剂量估计. 为DT进行校正可以提高吸收剂量计算的准确性,特别是在瘤中,这使得侦察剂的使用成为治疗剂的可靠预测剂.
科学领域:
- 核医学是一种核医学.
- 医学物理 医学物理
- 放射性药物疗法是一种放射性药物疗法.
背景情况:
- 在放射栓塞中,Ho-poly-L-乳酸 (Ho-PLLA) 微球为侦察和治疗管理 (SA和TA) 提供了双重用途.
- 在SPECT/CT成像中,量化和纠正死时间 (DT) 效应对于准确的吸收剂量 (AD) 估计至关重要.
研究的目的:
- 在Ho-PLLA放射栓塞中量化死时间 (DT) 对吸收剂量 (AD) 估计的影响.
- 通过比较AD值和分布来评估SA对TA的预测准确度.
- 为了评估TA剂量估计的不同DT校正方法.
主要方法:
- 在幻影中对Ho-PLLA活动源进行了成像,以评估随时间推移的DT效应.
- 对15名患者进行了SPECT/CT扫描,这些患者接受了166个Ho-PLLA的SA和TA,以检查肝病变.
- 使用局部能量沉积 (LED) 方法计算吸收剂量 (AD) 和分布,比较TA的三个DT校正策略.
主要成果:
- 对于超过250MBq的活动,死亡时间 (DT) 影响是显著的,导致过高估计.
- 在所有方法中,SA和TA AD值之间发现了强烈的线性相关性.
- DT校正,特别是针对瘤区域,显著改善了SA和TA吸收剂量之间的一致性,玛指数通过率达到92%的肝脏和87%的瘤.
结论:
- 死亡时间 (DT) 在Ho-PLLA放射栓塞中显著影响吸收剂量 (AD) 估计,特别是在瘤点中.
- 实施适当的DT校正方法可以提高TA的剂量测量评估的准确性.
- 精确的DT校正确保SA吸收剂量值能够准确预测TA吸收剂量值,从而验证SA的预测能力.
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