死时间损失对锝-99m六甲基丙烯胺肟定量测量脑血流量的影响。

Effect of deadtime loss on quantitative measurement of cerebral blood flow with technetium-99m hexamethylpropylene amine oxime.

作者信息

Inoue Y, Momose T, Ohtake T, Asai S, Yoshikawa K, Nishikawa J, Sasaki Y

机构信息

Department of Radiology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.

出版信息

Eur J Nucl Med. 1997 Nov;24(11):1418-21. doi: 10.1007/s002590050169.

DOI:10.1007/s002590050169

PMID:9371876

Abstract

Deadtime count loss may cause error in quantitative measurements with a gamma camera. We evaluated the effect of deadtime loss on the measurement of cerebral blood flow (CBF). Radionuclide angiography with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was performed in 20 patients. A reference source was placed on the periphery of the detector to monitor deadtime loss, and CBF was calculated based on the data of radionuclide angiography with and without deadtime correction. In ten patients injected with 1110 MBq of the tracer, the CBF value without correction was 9.9%+/-1.8% higher than that with correction. This shows that deadtime loss may cause significant overestimation. The difference between CBF values obtained with and without correction was smaller in ten patients with an injected dose of 370 MBq (3.0%+/-1.2%). These results suggest a substantial effect of deadtime loss on CBF as measured by radionuclide angiography and 99mTc-HMPAO.

摘要

死时间计数损失可能会导致γ相机定量测量出现误差。我们评估了死时间损失对脑血流量（CBF）测量的影响。对20例患者进行了锝-99m六甲基丙烯胺肟（99mTc-HMPAO）放射性核素血管造影。在探测器周边放置一个参考源以监测死时间损失，并根据有无死时间校正的放射性核素血管造影数据计算CBF。在注射1110MBq示踪剂的10例患者中，未校正的CBF值比校正后的高9.9%±1.8%。这表明死时间损失可能会导致显著高估。在注射剂量为370MBq的10例患者中，校正前后CBF值的差异较小（3.0%±1.2%）。这些结果表明，死时间损失对放射性核素血管造影和99mTc-HMPAO测量的CBF有实质性影响。