Error Analysis for the Determination of Cerebral Blood Flow with the Continuous Inhalation of 15O-Labeled Carbon Dioxide and Positron Emission Tomography

1982 ◽  
Vol 6 (1) ◽  
pp. 116-124 ◽  
Author(s):  
Stephen C. Jones ◽  
Joel H Greenberg ◽  
Martin Reivich
1995 ◽  
Vol 15 (1) ◽  
pp. 111-114 ◽  
Author(s):  
Eku Shimosegawa ◽  
Iwao Kanno ◽  
Jun Hatazawa ◽  
Hideaki Fujita ◽  
Hidehiro Iida ◽  
...  

To investigate the effect of the level of baseline cerebral blood flow (CBF) on local CBF augmentation by activation, we have used positron emission tomography to measure regional CBF (rCBF) in 12 normal volunteers with and without photic stimulation during hypocapnia, normocapnia, and hypercapnia. The increase in rCBF in the primary visual cortex by photic stimulation was 10.8 ± 3.1, 18.6 ± 9.3, and 19.5 ± 6.1 ml 100 ml−1 min−1 in hypo-, normo-, and hypercapnia, respectively. The increase was significantly smaller in hypocapnia than in normocapnia ( p < 0.005). The fractional CBF increase caused by the photic stimulation was the same in all breathing conditions. This result indicates that the magnitude of the CBF increase induced by neuronal activity correlates proportionally with the level of baseline CBF.


PEDIATRICS ◽  
1983 ◽  
Vol 72 (5) ◽  
pp. 589-601 ◽  
Author(s):  
Joseph J. Volpe ◽  
Peter Herscovitch ◽  
Jeffrey M. Perlman ◽  
Marcus E. Raichle

Of all patients with intraventricular hemorrhage, those with hemorrhagic intracerebral involvement exhibit the highest rates of mortality and neurologic morbidity and, indeed, account for the vast majority of all neurologic impairment in infants with intraventricular hemorrhage. Insight into the basic nature of the critical cerebral involvement requires determination of regional cerebral blood flow, previously not possible. Positron emission tomography (PET) now provides the capability of measuring regional cerebral blood flow with high resolution and little risk. In this study, we utilized PET in six premature infants (920 to 1,200 g) with major intraventricular hemorrhage and hemorrhagic intracerebral involvement to measure regional cerebral blood flow during the acute period (5 to 17 days of age). Cerebral blood flow was determined after intravenous injection of H2O, labeled with the positron-emitting isotope, 15O (oxygen 15). Findings were similar and dramatic in all six infants. In the area of hemorrhagic intracerebral involvement, little or no cerebral blood flow was detected. However, in addition, surprisingly, a marked two- to fourfold reduction in cerebral blood flow was observed throughout the affected hemisphere, well posterior and lateral to the intracerebral hematoma, including cerebral white matter and, to a lesser extent, frontal, temporal, and parietal cortex. In the one infant studied a second time, ie, at 3 months of age, the extent and severity of the decreased cerebral blood flows in the affected hemisphere were similar to those observed on the study during the neonatal period. At the three autopsies, the affected left hemisphere showed extensive infarction, corroborating the PET scans. These observations, the first demonstration of the use of PET in the determination of regional cerebral blood flow in the newborn, show marked impairments in regional cerebral blood flow in the hemisphere containing an apparently restricted intra cerebralhematoma, indicating that the hemorrhagic intracerebral involvement is only a component of a much larger lesion, ischemic in basic nature, ie, an infarction. This large ischemic lesion explains the poor neurologic outcome in infants with intraventricular hemorrhage and hemorrhagic intracerebral involvement.


1999 ◽  
Vol 11 (3) ◽  
pp. 97-102
Author(s):  
N. Van Eyken ◽  
H. D'haenen

SummaryPositron emission tomography is one of the most important techniques of functional imaging in psychiatry. This paper gives a synopsis of the findings in mood disorders: determination of brain glucose metabolism, cerebral blood flow and receptor studies. Investigation in a resting state as well as after activation are discussed.Although findings are somewhat discrepant hypometabolism, and/or hypoperfusion, most often in frontal and limbic areas are frequently described. Further research is needed, and standardization of the methodology would be most wellcome.


2001 ◽  
Vol 21 (12) ◽  
pp. 1472-1479 ◽  
Author(s):  
Hidehiko Okazawa ◽  
Hiroshi Yamauchi ◽  
Kanji Sugimoto ◽  
Hiroshi Toyoda ◽  
Yoshihiko Kishibe ◽  
...  

To evaluate changes in cerebral hemodynamics and metabolism induced by acetazolamide in healthy subjects, positron emission tomography studies for measurement of cerebral perfusion and oxygen consumption were performed. Sixteen healthy volunteers underwent positron emission tomography studies with15O-gas and water before and after intravenous administration of acetazolamide. Dynamic positron emission tomography data were acquired after bolus injection of H215O and bolus inhalation of15O2. Cerebral blood flow, metabolic rate of oxygen, and arterial-to-capillary blood volume images were calculated using the three-weighted integral method. The images of cerebral blood volume were calculated using the bolus inhalation technique of C15O. The scans for cerebral blood flow and volume and metabolic rate of oxygen after acetazolamide challenge were performed at 10, 20, and 30 minutes after drug injection. The parametric images obtained under the two conditions at baseline and after acetazolamide administration were compared. The global and regional values for cerebral blood flow and volume and arterial-to-capillary blood volume increased significantly after acetazolamide administration compared with the baseline condition, whereas no difference in metabolic rate of oxygen was observed. Acetazolamide-induced increases in both blood flow and volume in the normal brain occurred as a vasodilatory reaction of functioning vessels. The increase in arterial-to-capillary blood volume made the major contribution to the cerebral blood volume increase, indicating that the raise in cerebral blood flow during the acetazolamide challenge is closely related to arterial-to-capillary vasomotor responsiveness.


2003 ◽  
Vol 98 (5) ◽  
pp. 1101-1111 ◽  
Author(s):  
Kenichi Ogawa ◽  
Takeshi Uema ◽  
Nobutaka Motohashi ◽  
Masami Nishikawa ◽  
Harumasa Takano ◽  
...  

Background The precise neural mechanisms of propofol anesthesia in humans are still unknown. The authors examined the acute effects of propofol on regional cerebral blood flow (rCBF) using positron emission tomography in patients with severe depression. Methods In six severely depressed patients (mean age, 55.0 yr) scheduled for electroconvulsive therapy, anesthetic levels were monitored by electroencephalography, and rCBF was serially quantified in the awake, sedated, and anesthetized states. The authors used high-resolution positron emission tomography with 15O-labeled water and statistical parametric mapping 99 for imaging and analysis of the data. Results Global cerebral blood flow showed sharp decreases from the awake level during the administration of propofol, decreasing 26.8% in the sedated state and 54.4% in the anesthetized state. Moreover, a dose effect was seen in both parietal cortices and the left lateral prefrontal region with larger regions of relative decrease in rCBF at higher propofol doses. At the higher dose, the values of rCBF in the pulvinar nucleus of the thalamus, the pontine tegmentum, and the cerebellar cortex were also affected. Meanwhile, there were few changes of relative rCBF in the basal frontal lobes during both sedated and anesthetized states. Conclusions As in earlier studies using normal subjects, pronounced suppression in rCBF in the brain stem reticular formation, the thalamus, and the parietal association cortex occurred even in severely depressed patients. However, previously reported decreases in rCBF in the basal frontal lobe were absent in depressed patients.


2000 ◽  
Vol 92 (6) ◽  
pp. 1009-1015 ◽  
Author(s):  
Seiji Yamamoto ◽  
Weiyu Teng ◽  
Shigeru Nishizawa ◽  
Takeharu Kakiuchi ◽  
Hideo Tsukada

Object. The hydroxyl radical scavenger (±)-N,N′-propylenedinicotinamide (AVS) has been shown to ameliorate the occurrence of vasospasm following experimental subarachnoid hemorrhage (SAH) and to reduce the incidence of delayed ischemic neurological deficits (DINDs) in patients with SAH. The authors investigated whether prophylactic administration of AVS could improve cerebral blood flow (CBF) and cerebral glucose utilization (CGU) following SAH in rats.Methods. Anesthetized rats were subjected to intracisternal injection of blood (SAH group) or saline (control group). Either AVS (1 mg/kg/min) or saline (vehicle group) was continuously injected into the rat femoral vein. Forty-eight hours later, positron emission tomography scanning was used with the tracers 15O-H2O and 18F-2-fluoro-d-glucose to analyze quantitatively CBF and CGU, respectively, in the frontoparietal and occipital regions (12 regions of interest/group).In SAH rats receiving only vehicle, CBF decreased significantly (p < 0.05, Tukey's test) and CGU tended to decrease, compared with values obtained in control (non-SAH) rats receiving vehicle. In rats that were subjected to SAH, administration of AVS significantly (p < 0.05, Tukey's test) improved CBF and CGU in both the frontoparietal and occipital regions compared with administration of vehicle alone.Conclusions. Prophylactic administration of AVS improves CBF and CGU in the rat brain subjected to SAH, and can be a good pharmacological treatment for the prevention of DINDs following SAH.


2012 ◽  
Vol 18 (3) ◽  
pp. 264-274 ◽  
Author(s):  
N. Kawai ◽  
M. Kawanishi ◽  
A. Shindou ◽  
N. Kudomi ◽  
Y. Yamamoto ◽  
...  

Balloon test occlusion (BTO) of the internal carotid artery (ICA) combined with cerebral blood flow (CBF) study is a sensitive test for predicting the outcome of permanent ICA occlusion. However, false negative results sometimes occur using single photon emission tomography (SPECT). We have recently developed a rapid positron emission tomography (PET) protocol that measures not only the CBF but also the cerebral oxygen metabolism before and during BTO in succession. We measured acute changes in regional CBF and OEF/CMRO2 before and during BTO in three cases with large or giant cerebral aneurysms using the rapid PET protocol. Although no patients showed ischemic symptoms during BTO, PET studies exhibited mildly to moderately decreased CBF (9∼34%) compared to the values obtained before BTO in all cases. The average OEF during BTO was significantly increased (21% and 43%) than that of before BTO in two cases. The two cases were considered to be non-tolerant for permanent ICA occlusion and treated without ICA sacrifice. Measurement of the CBF and OEF/CMRO2 using a rapid PET protocol before and during BTO is feasible and can be used for accurate assessment of tolerance prediction in ICA occlusion.


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