Daniel G B, Bahr A, Dykes J A, DeNovo R, Young K, Smith G T
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville 37901-1071, USA.
J Nucl Med. 1996 Nov;37(11):1846-9.
Quantitative hepatobiliary scintigraphy aids in the diagnosis of hepatic disease. Two scintigraphic parameters that have great value in discriminating between hepatocellular and biliary disease are hepatic extraction fraction (HEF), which is a measure of the hepatic extraction efficiency (HEE), and hepatic excretion rate. It is generally accepted that hepatic extraction fraction is normally 100%, but a review of the literature provided little information on the actual HEF of 99mTc-mebrofenin.
We determined the HEE of 99mTc-mebrofenin in nine normal dogs after direct injection into the afferent hepatic vasculature using a two-compartment model. The forward and reverse rate constants for the two-compartment model were solved by a simple graphic approach and a more complex numerical approach using a nonlinear least squares algorthm. The HEEs were determined using both methods.
The HEE for the graphic and numerical methods of analysis were not significantly different and were calculated to be 92.2 +/- 4.75% (mean +/- s.d.) and 91.2 +/- 4.44% (mean +/- s.d.) by each method, respectively. The half-time clearance of 99mTc-mebrofenin was 19.10 +/- 4.86 min (mean +/- s.d.).
This study validates the assumption that the normal HEE of 99mTc-mebrofenin is nearly 100%, barring species differences.
定量肝胆闪烁扫描术有助于肝病的诊断。在区分肝细胞性疾病和胆汁性疾病方面具有重要价值的两个闪烁扫描参数是肝摄取分数（HEF），它是肝摄取效率（HEE）的一种度量，以及肝排泄率。一般认为肝摄取分数正常情况下为100%，但对文献的回顾几乎没有提供关于99mTc - 美罗芬宁实际肝摄取分数的信息。
我们使用双室模型，将99mTc - 美罗芬宁直接注入九条正常犬的肝传入血管后，测定其肝摄取效率。双室模型的正向和反向速率常数通过简单的图形法和使用非线性最小二乘法的更复杂的数值法求解。两种方法都用于测定肝摄取效率。
图形分析方法和数值分析方法的肝摄取效率无显著差异，每种方法计算得出的肝摄取效率分别为92.2±4.75%（平均值±标准差）和91.2±4.44%（平均值±标准差）。99mTc - 美罗芬宁的半衰期清除时间为19.10±4.86分钟（平均值±标准差）。
本研究验证了这样一个假设，即99mTc - 美罗芬宁的正常肝摄取效率接近100%，排除物种差异。
