1964 Volume 13 Issue 4 Pages 308-317
A new method for measurement of mean cerebral circulation time has been successfully tested in this study as follows.
When one of the scintillation detector head directs to the Willis' circle on the temporal area of human head and the other one directs to the cervical artery at the same side, two radioangiograms can be recorded.
Therefore on the curve of radiocraniogram, if one indicates by Ac and Dc the appearance time of tracer and the disapperance time of maximal bolus, these may be represented as the upstanding point and the initial point of semilogarithmic phase.
On the other hand, if Aa, Pa, Pv and Dv indicate the arterial appearance time, the arterial peak time, the venous peak time and the venous disappearance time on the cervical radioangiogram each other, and let Ma and Mv represent the mean point of arterial and venous tracer concentration, the following equation shall be obtained.
Mean sinus-jugular balb circulation time=Dv-Dc
Mean carotis-basilar artery circulation time=Ca-Pa
and mean cerebral circulation time (MCCT)
=Mv-Ma- { (Ca-Pa) + (Dv-Dc) }
where, (Ca-Pa) is negligible
Consequently MCCT≅Mv-Ma (Dv-Dc)
The actual data of MCCT which were measured by this method, were 6.7 sec (average) on normal adults, 7.6 sec on hypertensives, 7.8 sec on post-cerebrovascular accidents and 8.3 sec on cerebral arteriosclerosis.
The cerebral blood flow should significant reduction on the cases with cerebral vascular diseases which were observed the prolonged MCCT.
