Noninvasive Method of Estimating Human Newborn Regional Cerebral Blood Flow

A noninvasive method of estimating regional cerebral blood flow (rCBF) in premature and full-term babies has been developed. Based on a modification of the xenon-133 inhalation rCBF technique, this method uses eight extracranial NaI scintillation detectors and an i. v. bolus injection of xenon-133 (∼0.5 mCi/kg). Arterial xenon concentration was estimated with an external chest detector. Cerebral blood flow was measured in 15 healthy, neurologically normal premature infants. Using Obrist's method of two-compartment analysis, normal values were calculated for flow in both compartments, relative weight and fractional flow in the first compartment (gray matter), initial slope of gray matter blood flow, mean cerebral blood flow, and initial slope index of mean cerebral blood flow. The application of this technique to newborns, its relative advantages, and its potential uses are discussed.

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Accuracy of methods for calculating cerebral blood flow from intracarotid xenon-133 injection

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1980.238.5.h750 ◽

1980 ◽

Vol 238 (5) ◽

pp. H750-H758

Author(s):

J. P. Marc-Vergnes ◽

P. Celsis ◽

J. P. Charlet ◽

G. Setien

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Gray Matter ◽

Relative Weight ◽

Compartmental Analysis ◽

Optimization Method ◽

Initial Slope ◽

Method Of Calculation ◽

Blood Flows ◽

Xenon 133

The accuracy of the three commonly used methods, the initial slope analysis, the stochastic analysis, and the compartmental analysis, for calculating mean cerebral blood flow from xenon-133 clearance curves was studied with the use of computer-generated and real curves. The accuracy of calculation was affected by the cutoff time of the curve, by the level of the compartmental blood flows to white and gray matter and by the ratio of these flow levels, by the relative weight of gray matter, and by the choice of the method of calculation. None of the methods was clearly superior to the others. Each had its own defects that render it more or less suitable for different situations. All three methods generally overestimated mean cerebral blood flow. This overestimation was greater the lower the flow. A curve-fitting index was devised which can be used to check the validity of the bicompartmental model when using compartmental analysis. This same index can provide, though not always, an estimate of the error in the calculation of mean cerebral blood flow when an optimization method is used.

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Compartmental abnormalities of regional cerebral blood flow in children with head trauma

Journal of Neurosurgery ◽

10.3171/jns.1972.36.4.0463 ◽

1972 ◽

Vol 36 (4) ◽

pp. 463-470 ◽

Cited By ~ 26

Author(s):

Samuel S. Kasoff ◽

Lawrence H. Zingesser ◽

Kenneth Shulman

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Gray Matter ◽

Regional Cerebral Blood Flow ◽

Head Injuries ◽

Relative Weight ◽

Compartmental Analysis ◽

Regional Cerebral Blood ◽

Content Type ◽

Pediatric Age Group

✓ Regional cerebral blood flow (CBFr) and compartmental analysis in a series of children with closed head injuries have demonstrated abnormalities of both rate and distribution of blood flow. The most frequent derangement was a triphasic flow pattern overlying one or more regions of traumatized brain. The rate of flow in this third compartment is two to five times the rate of normal gray matter flow; while the relative weight of the compartment varies between 3.5% and 15%. The pathophysiology of this third, rapid compartment of flow is discussed, and the argument put forth that such flow does not represent hyperperfusion but rather an ischemia of the gray matter because such blood flow is not available to the tissue for nutrition. If this is so, it may well be a cause of permanent sequelae in the pediatric age group.

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Chroma-Memo-Flow Technique for Rapid Sequential Analysis of Regional Cerebral Blood Flow (rCBF) Responses

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100024689 ◽

1978 ◽

Vol 5 (1) ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Jørn Overgaard

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Sequential Analysis ◽

Initial Slope ◽

Functional Tests ◽

Regional Cerebral Blood ◽

Flow Calculation ◽

Channel Memory ◽

Xenon 133

SUMMARY:This is the first report of a method of sequential regional cerebral blood flow (rCBF) analysis, called Croma-Memo-Flow. This technique is a computerized modification of the initial slope method of regional cerebral blood flow (rCBF init.), allowing temporal resolution of the flow pattern by calculation of the slopes of sequential segments of the initial 1-2 minutes of the Xenon-133 washout curve. The same theoretical analysis applies to this method as to the rCBF init. method. Each flow calculation is based on the slope of a discrete 16 second segment of the initial washout; and each second the segment is advanced by one second. A new flow calculation is made each second and is displayed as a color coded map on a TV screen. Each map is labelled, indicating the time in seconds following Xenon injection, and sequential rCBF changes during the clearance period can be immediately visualized. This allows for almost instantaneous analysis and display of rapid or transient rCBF responses to activation and deactivation of the cerebral cortices.The data is stored in a 35 channel memory for deliberate replay, photography, and analysis.Functional tests may be applied during the initial washout period and both the magnitude and chronological relationships of the evoked regional cerebrovascular responses observed. A clinical study is presented to illustrate the possibilities of applying the technique to assess cortical reactivity.

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Regional Cerebral Blood Flow during Rest and Skilled Hand Movements by Xenon-133 Inhalation and Emission Computerized Tomography

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1981.42 ◽

1981 ◽

Vol 1 (4) ◽

pp. 385-389 ◽

Cited By ~ 34

Author(s):

Martin Lauritzen ◽

Leif Henriksen ◽

Niels A. Lassen

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Single Photon ◽

Photon Emission ◽

Hand Movements ◽

Regional Cerebral Blood ◽

Symmetric Pattern ◽

Xenon 133 ◽

The Right

Regional cerebral blood flow (CBF) was studied in 16 normal adult volunteers during rest and in 10 the study was repeated during skilled hand movements. A fast-rotating (“dynamic”), single-photon emission computerized tomograph (ECT) with four detector heads was used. Xenon-133 was inhaled over a 1-min period at a concentration of 10 mCi/L. The arrival and washout of the radioisotope was recorded during four 1-min periods. Two slices, 2 cm thick, 7 and 12 cm above the orbitomeatal line were obtained in every study. CBF averaged 60 ml/100 g/min (SD ± 11) in the lower slice and 51 ml/100 g/min (SD ± 13) in the upper slice. A symmetric pattern comparing right to left sides was found in both slices. Finger tapping and writing with the right hand increased CBF in specific areas of the upper slice: in the contralateral hand area by 35 ± 15% ( p < 0.025), and in the supplementary motor area on both sides by 34 ± 15% ( p < 0.025).

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