Makino K, Masuda Y, Gotoh S
Department of Neurosurgery, Asahikawa Red Cross Hospital.
Kaku Igaku. 1998 Jul;35(6):405-12.
A correction method was proposed for measurement of the regional cerebral blood flow using one-point arterial blood sampling and a microsphere model with N-isopropyl-p-(123I)iodoamphetamine (123I-IMP). Instead of using continuous arterial blood sampling octanol-extracted counts, one-point arterial sampling whole blood counts corrected by the whole brain count ratio using 1-minute planar SPECT images were employed. The experimental subjects were 189 patients with cerebrovascular disorders. 123I-IMP, 222 MBq, was administered by intravenous infusion. Continuous arterial blood sampling was carried out for 5 minutes, and arterial blood was also sampled once at 5 minutes after 123I-IMP administration. Then the whole blood count of the one-point arterial sampling was compared with the octanol-extracted count of the continuous arterial sampling. A positive correlation was found between the two values (r = 0.87, p < 0.001). The correction method was carried out by calculation as follows. The ratio of the continuous sampling octanol-extracted count (OC) to the one-point sampling whole blood count (TC5) was compared with the whole brain count ratio (5:29 ratio, Cn) using 1-minute planar SPECT images, centering on 5 and 29 minutes after 123I-IMP administration. Correlation was found between the two values (r = 0.72, p < 0.001). The following relationship was shown from the correlation equation. OC/TC5 = 0.390969 x Cn-0.08924. Based on this correlation equation, we calculated the theoretical continuous arterial sampling octanol-extracted count (COC). COC = TC5 x (0.390969 x Cn-0.08924). There was good correlation between the value calculated with this equation and the actually measured value (r = 0.94, p < 0.001). The coefficient improved to r = 0.94 from the r = 0.87 obtained before using the 5:29 ratio for correction. For 23 of these 189 cases, another one-point arterial sampling was carried out at 6, 7, 8, 9 and 10 minutes after the administration of 123I-IMP. The correlation coefficient was also improved for these other point samplings when this correction method using the 5:29 ratio was applied. It was concluded that it is possible to obtain highly accurate input functions, i.e., calculated continuous arterial sampling octanol-extracted counts, using one-point arterial sampling whole blood counts by performing correction using the 5:29 ratio.
提出了一种校正方法，用于使用单点动脉血样采集和带有N-异丙基-p-(123I)碘安非他明(123I-IMP)的微球模型来测量局部脑血流量。不是使用连续动脉血样采集的辛醇提取计数，而是采用通过使用1分钟平面SPECT图像的全脑计数比率校正的单点动脉血样采集全血计数。实验对象为189例脑血管疾病患者。通过静脉输注给予222 MBq的123I-IMP。进行5分钟的连续动脉血样采集，并且在给予123I-IMP后5分钟也采集一次动脉血。然后将单点动脉血样采集的全血计数与连续动脉血样采集的辛醇提取计数进行比较。发现这两个值之间存在正相关(r = 0.87，p < 0.001)。校正方法通过如下计算进行。将连续采样辛醇提取计数(OC)与单点采样全血计数(TC5)的比率与使用1分钟平面SPECT图像、以123I-IMP给药后5和29分钟为中心的全脑计数比率(5:29比率，Cn)进行比较。发现这两个值之间存在相关性(r = 0.72，p < 0.001)。从相关方程得出以下关系。OC/TC5 = 0.390969×Cn - 0.08924。基于此相关方程，我们计算了理论连续动脉采样辛醇提取计数(COC)。COC = TC5×(0.390969×Cn - 0.08924)。用该方程计算的值与实际测量值之间存在良好的相关性(r = 0.94，p < 0.001)。校正系数从使用5:29比率校正前获得的r = 0.87提高到了r = 0.94。在这189例病例中的23例中，在给予123I-IMP后6、7、8、9和10分钟进行了另一次单点动脉血样采集。当应用这种使用5:29比率的校正方法时，这些其他点采样的相关系数也得到了提高。得出的结论是，通过使用5:29比率进行校正，使用单点动脉血样采集全血计数有可能获得高度准确的输入函数，即计算出的连续动脉采样辛醇提取计数。
