A model for regional cerebral oxygen distribution during continuous inhalation of 15O2, C15O, and C15O2.
A model for regional cerebral oxygen distribution during continuous inhalation of 15O2, C15O, and C15O2.
复制标题
连续吸入 15O2、C15O 和 C15O2 期间的局部脑氧分布模型。
DOI：
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发表时间：
1978
影响因子：
9.3
通讯作者：
J. Taveras
中科院分区：
文献类型：
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作者：
R. Subramanyam;N. Alpert;B. Hoop;G. Brownell;J. Taveras
在持续吸入C15O、C15O2和15O2的过程中进行平衡正电子脑部扫描。吸入C15O标记了血红蛋白，而C15O2瞬间将稳定的水标记为H215O。在持续吸入15O2的过程中，身体组织根据局部新陈代谢的比例从血液中提取15O2，最终转化为代谢水。在吸入6-8分钟后，建立了一个稳定的平衡状态，示踪剂的流入被放射性衰变(T1/2=2分钟)和生物去除所导致的消失所平衡。推导了C15O、C15O2/H_215O和150/H_215O稳态分布的数学模型。主要结果是：a)C15O的稳态分布对血流量的变化不敏感，本质上是测量血容量。B)吸入C15O2过程中H_215O的分布与血流量有关，尽管是非线性的。吸入15O2过程中H_(15)O的分布与吸氧分数呈线性关系，与血流量呈非线性关系。D)通过用C15O2图像逐点分割15O2图像，可以消除对15O2稳态图像中血流的依赖。
Equilibrium positron brain scans were obtained during continuous inhalation of C15O, C15O2, and 15O2. Inhalation of C15O labels hemoglobin, whereas C15O2 instantaneously labels stable water to H215O. During the continuous inhalation of 15O2, body tissues extract it from the blood in proportion to local metabolism and ultimately convert it to water of metabolism. After 6-8 min of inhalation, a steady-state equilibrium is established in which the inflow of tracer is balanced by its disappearance due to radioactive decay (T1/2 = 2 min) and biologic removal. Mathematical models of the steady-state distributions of C15O, C15O2/H215O, and 15O/H215O are derived. The major results are: a) The steady-state distribution of C15O is insensitive to variations in blood flow and essentially measures blood volume. b) The distribution of H215O during inhalation of C15O2 is dependent, though nonlinearly, on blood flow. c) The distribution of H215O during inhalation of 15O2 depends linearly on the oxygen extraction fraction and nonlinearly on blood flow. d) The dependence on blood flow in the 15O2 steady-state image can be removed by the division, point by point, of the 15O2 image by the C15O2 image.