锝-99m-六甲基丙二胺肟在人脑内的动力学行为及使用动态单光子发射计算机断层扫描定量脑血流量

Kinetic behavior of technetium-99m-HMPAO in the human brain and quantification of cerebral blood flow using dynamic SPECT.

作者信息

Murase K, Tanada S, Fujita H, Sakaki S, Hamamoto K

机构信息

Deparment of Radiology and Neurosurgery, Ehime University School of Medicine, Japan.

出版信息

J Nucl Med. 1992 Jan;33(1):135-43.

PMID:1730979

Abstract

The kinetic behavior of 99mTc-hexamethylpropyleneamine oxime (HMPAO) in the human brain was investigated in 11 patients with various brain diseases (176 regions), using dynamic SPECT and a four-compartment model with five parameters (K1: rate constant for the transport of HMPAO from blood to brain, K2: backdiffusion from brain to blood, K3: conversion to a hydrophilic form in the brain, K5: conversion to a nondiffusible form in the blood, and fa: fraction of radioactivity attributable to the vascular compartment). Although K1 correlated well with cerebral blood flow (CBF) measured by the 133Xe inhalation method (Xe-CBF) (r = 0.888), its value was underestimated by 28.9% +/- 11.9%, indicating a low extraction fraction (E) for HMPAO. From E = K1/CBF, a regression equation of E = 0.857 - 0.00335. Xe-CBF was obtained. Significant correlations were observed for K2 versus Xe-CBF (r = 0.679), for K3 versus Xe-CBF (r = 0.483), for K3/(K2 + K3) versus Xe-CBF (r = -0.487), for K3/K2 versus Xe-CBF (r = -0.501), and for K2 + K3 versus Xe-CBF (r = 0.655), but not for K1/K2 versus Xe-CBF (r = 0.005). Thus, this model was useful for elucidating the kinetic behavior of HMPAO in the human brain, and correction for E appears to be indispensable for accurate CBF quantification using HMPAO.

摘要

采用动态单光子发射计算机断层扫描（SPECT）和具有五个参数的四室模型（K1：99m锝-六甲基丙烯胺肟（HMPAO）从血液到脑的转运速率常数；K2：从脑到血液的反向扩散；K3：在脑内转化为亲水性形式；K5：在血液中转化为非扩散性形式；fa：归因于血管腔室的放射性分数），对11例患有各种脑部疾病的患者（176个区域）的人脑内99mTc-HMPAO的动力学行为进行了研究。尽管K1与通过吸入133氙方法（Xe-CBF）测量的脑血流量（CBF）具有良好的相关性（r = 0.888），但其值被低估了28.9%±11.9%，表明HMPAO的提取分数（E）较低。根据E = K1/CBF，得到回归方程E = 0.857 - 0.00335·Xe-CBF。观察到K2与Xe-CBF之间存在显著相关性（r = 0.679），K3与Xe-CBF之间存在显著相关性（r = 0.483），K3/(K2 + K3)与Xe-CBF之间存在显著相关性（r = -0.487），K3/K2与Xe-CBF之间存在显著相关性（r = -0.501），以及K2 + K3与Xe-CBF之间存在显著相关性（r = 0.655），但K1/K2与Xe-CBF之间不存在显著相关性（r = 0.005）。因此，该模型有助于阐明HMPAO在人脑中的动力学行为，并且对于使用HMPAO进行准确的CBF定量而言，对E进行校正似乎是必不可少的。