[Normal CBF values by the ARG method using IMP SPECT: comparison with a conventional microsphere model method].
N-isopropyl-p[123I]iodoamphetamine (IMP) has been used as a flow tracer for SPECT, and measurement of cerebral blood flow (CBF) using IMP has been performed by conventional microsphere model method (MS method). Recently, the ARG method for measuring CBF by using IMP with one SPECT scan and one point blood sampling has been developed. This method was based on two-compartment model. In the present study, normal CBF values were measured in ten male healthy subjects (mean age +/- S.D.: 29.8 +/- 6.01, age range: 23-41) by the ARG and the MS methods. The mean CBF values (+/- S.D.) for the ARG method in which the Vd value was assumed to be 50 ml/ml were 41.7 +/- 9.4, 31.1 +/- 5.0, 40.7 +/- 9.7, 41.5 +/- 10.0, 38.2 +/- 9.2, 39.0 +/- 9.4, 41.9 +/- 10.6, 38.7 +/- 8.0 and 30.0 +/- 7.7 ml/100 ml/min in the cerebellum, pons, thalamus, basal ganglia, frontal, temporal, parietal, occipital lobe cortex and centrum semiovale, respectively. The mean CBF values for the MS method were 46.8 +/- 8.4, 37.5 +/- 5.6, 45.8 +/- 8.6, 46.5 +/- 8.9, 43.7 +/- 8.3, 44.4 +/- 8.7, 46.8 +/- 9.3, 44.3 +/- 7.3 and 36.3 +/- 8.1 ml/100 ml/min, respectively. The mean CBF values in the cerebral cortex region for the ARG method were lower than those previously reported by PET. This would be caused by low first-pass extraction fraction of IMP compared with oxygen-15 labeled water. The mean CBF values for the MS method were higher than those for the ARG method against previous studies. As reasons for this, errors in estimation of the SPECT brain counts at 8 min in the MS method were considered.
Ito
H
H
Department of Nuclear Medicine and Radiology, Tohoku University, Miyagi, Japan.
Ishii
K
K
Kinoshita
T
T
Koyama
M
M
Kawashima
R
R
Ono
S
S
Fukuda
H
H
D000328:Adult; D000662:Amphetamines; D001921:Brain / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D006801:Humans; D007457:Iodine Radioisotopes; D020367:Iofetamine; D008297:Male; D008863:Microspheres; D012016:Reference Values; D015899:Tomography, Emission-Computed, Single-Photon
D000662:Amphetamines; D007457:Iodine Radioisotopes; D020367:Iofetamine