[Estimation of integral value of input function for the quantification of cerebral blood flow with 123I-IMP using one-point arterial blood sampling].
Cerebral blood flow (CBF) has been measured using a microsphere model with octanol-extracted radioactivity counts (integral value of input function). We developed a new method estimating the integral value of input function. First, we fitted the whole brain time-activity curves early after intravenous injection of N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) by the least-squares method. Second, we differentiated this equation. Third, we calibrated it using octanol-extracted radioactivity counts of the arterial blood sampled at 5 min. Finally, we integrated it. A significant correlation was found between the integral values obtained using a new method and those obtained using the continuous arterial blood sampling data (y = 1.048x-1206, r = 0.984). The errors between the CBF values obtained using a new method and those obtained using the 5-min continuous arterial blood sampling was 6.88 +/- 4.78%. Measurement of integral values of the input function using a new method with one-point arterial blood sampling is less invasive and convenient, and is not influenced by cardiopulmonary disease or smoking. Therefore, it would be useful for the routine measurement of CBF.
Fujioka
H
H
Department of Radiology, Matsuyama Shimin Hospital.
Murase
K
K
Inoue
T
T
Ishimaru
Y
Y
Akamune
A
A
Yamamoto
Y
Y
Tanada
S
S
Ikezoe
J
J
D000662:Amphetamines; D001800:Blood Specimen Collection; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D007457:Iodine Radioisotopes; D020367:Iofetamine; D008863:Microspheres; D008954:Models, Biological; D019275:Radiopharmaceuticals; D012588:Scintillation Counting
D000662:Amphetamines; D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D020367:Iofetamine