An alternative approach to estimation of the brain perfusion index for measurement of cerebral blood flow using technetium-99m compounds

Cerebral blood flow (CBF) can be quantified noninvasively using the brain perfusion index (BPI), determined from radionuclide angiographic data generated with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO). Previously, the BPI has been calculated using graphical analysis (GA); however, the GA method is greatly affected by the first-pass extraction fraction and retention fraction, which are not only variable, but lower in cases with an increased CBF, such as after the administration of acetazolamide. Thus, GA-calculated BPI values (BPIG) may not reflect the absolute CBF. The objective of this study was to use the spectral analysis of radionuclide angiographic data collected using 99mTc-HMPAO to examine changes in the BPI after the administration of acetazolamide. We studied the CBF of both cerebral hemispheres in six healthy male volunteers; the BPI was measured at rest and after the intravenous administration of 1 g of acetazolamide. In all participants, an H215O positron emission tomography (PET) examination was also performed, and the spectral analysis—calculated BPI values (BPIS) and BPIG values were compared with the actual CBF measured using H215O PET (mCBFPET). The BPIS was 1.070 ± 0.051 (mean ± SD) at rest and 1.497 ± 0.098 after acetazolamide; the corresponding BPIG values were 0.646 ± 0.073 and 0.721 ± 0.107. The BPIS values were significantly correlated with the mCBFPET values, whereas the BPIG values were not. According to the BPIS values, the increase in BPI after the intravenous administration of acetazolamide was 40.1 ± 8.4%, as opposed to an increase of only 11.3 ± 6.5% according to the BPIG values. These results suggest that the spectral analysis of 99mTc-HMPAO—generated data yields a more reliable BPI than GA for the quantification of CBF after acetazolamide administration.

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Vorläufige Ergebnisse von 99mTc-HMPAO-SPECT-Untersuchungen bei endogenen Psychosen

Nuklearmedizin ◽

10.1055/s-0038-1629475 ◽

1989 ◽

Vol 28 (03) ◽

pp. 88-91

Author(s):

J. Schröder ◽

H. Henningsen ◽

H. Sauer ◽

P. Georgi ◽

K.-R. Wilhelm

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Regions Of Interest ◽

Post Mortem ◽

Regional Cerebral Blood ◽

Hmpao Spect ◽

Endogenous Psychoses ◽

The Brain ◽

99Mtc Hmpao

18 psychopharmacologically treated patients (7 schizophrenics, 5 schizoaffectives, 6 depressives) were studied using 99mTc-HMPAO-SPECT of the brain. The regional cerebral blood flow was measured in three transversal sections (infra-/supraventricular, ventricular) within 6 regions of interest (ROI) respectively (one frontal, one parietal and one occipital in each hemisphere). Corresponding ROIs of the same section in each hemisphere were compared. In the schizophrenics there was a significantly reduced perfusion in the left frontal region of the infraventricular and ventricular section (p < 0.02) compared with the data of the depressives. The schizoaffectives took an intermediate place. Since the patients were treated with psychopharmaca, the result must be interpreted cautiously. However, our findings seem to be in accordance with post-mortem-, CT- and PET-studies presented in the literature. Our results suggest that 99mTc-HMPAO-SPECT may be helpful in finding cerebral abnormalities in endogenous psychoses.

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Neuroimaging in Drug Discovery and Development: Paradigms for Accelerating New Drug Availability

Journal of Pharmacy Practice ◽

10.1106/bx9p-gcm4-gtef-jghn ◽

2001 ◽

Vol 14 (5) ◽

pp. 407-415

Author(s):

John T. Metz ◽

Malcolm D. Cooper ◽

Terry F. Brown ◽

Leann H. Kinnunen ◽

Declan J. Cooper

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Glucose Metabolism ◽

Phase Ii ◽

New Drugs ◽

Central Effects ◽

Drug Discovery And Development ◽

Psychological Tasks ◽

The Brain ◽

Phase Iv

The process of discovering and developing new drugs is complicated. Neuroimaging methods can facilitate this process. An analysis of the conceptual bases and practical limitations of different neuroimaging modalities reveals that each technique can best address different kinds of questions. Radioligand studies are well suited to preclinical and Phase II questions when a compound is known or suspected to affect well-understood mechanisms; they are also useful in Phase IV to characterize effective agents. Cerebral blood flow studies can be extremely useful in evaluating the effects of a drug on psychological tasks (mostly in Phase IV). Glucose metabolism studies can answer the simplest questions about whether a compound affects the brain, where, and how much. Such studies are most useful in confirming central effects (preclinical and early clinical phases), in determining effective dose ranges (Phase II), and in comparing different drugs (Phase IV).

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Atlas of 99mTc-HMPAO SPECT brain perfusion in pediatric brain disorders

Journal of Clinical Images and Medical Case Reports ◽

10.52768/2766-7820/1061 ◽

2021 ◽

Vol 2 (2) ◽

Author(s):

Saleh A Othman ◽

Keyword(s):

Blood Flow ◽

Neuronal Activity ◽

Pediatric Patients ◽

Brain Perfusion ◽

Brain Disorders ◽

Hmpao Spect ◽

Perfusion Scan ◽

Pediatric Brain ◽

The Brain ◽

99Mtc Hmpao

Background: Blood flow to the brain is in parallel with brain metabolism in almost all brain disorders except in brain tumors and therefore regional cerebral blood flow can be used as a marker of metabolic brain activity and hence it is closely linked to neuronal activity, the activity distribution is presumed to reflect neuronal activity levels in different areas of the brain. Purpose: The aim of this work is to demonstrate to pediatrician in general and pediatric neurologist in particular the variations in cerebral perfusion during normal development which should be taken into consideration at the time of interpreting SPECT brain perfusion scan in different pediatric brain disorders. Method: Brain SPECT was performed 10 minutes after an intravenous injection of 11.1 MBq/kg (0.3 mCi/kg), and the minimum dose is 185 MBq (5 mCi) of 99mTc-HMPAO (4). Results: This was a retrospective analysis of SPECT brain perfusion scan of pediatric patients performed between October 2015 and December 2019 at our institution. We selected normal and abnormal studies in pediatric population with age range (5 months - 14 years). Conclusion: Although anatomic cross sectional imaging give details of neurological structural changes, SPECT perfusion mirrors indirectly both metabolic and neuronal activity changes. Therefore, accurate interpretation of SPECT perfusion will consolidate its role as part of the diagnostic protocol and used when the findings of other imaging modalities do not explain the symptoms or fail partially or completely in determining the etiology of brain disorders in pediatric patients.

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Effects of Cytoflavin and Neuronol on Morphological Changes in the Brain and Survival of Rats with Ischemic Disturbances in Cerebral Blood Flow

Bulletin of Experimental Biology and Medicine ◽

10.1023/b:bebm.0000035145.08914.e8 ◽

2004 ◽

Vol 137 (4) ◽

pp. 411-414 ◽

Cited By ~ 1

Author(s):

V. V. Bulon ◽

I. B. Krylova ◽

N. R. Evdokimova ◽

A. L. Kovalenko ◽

L. E. Alekseeva ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Morphological Changes ◽

The Brain

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Use of 19F NMR Spectroscopy for Measurement of Cerebral Blood Flow: A Comparative Study Using Microspheres

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1989.122 ◽

1989 ◽

Vol 9 (6) ◽

pp. 886-891 ◽

Cited By ~ 31

Author(s):

David Barranco ◽

Leslie N. Sutton ◽

Sandra Florin ◽

Joel Greenberg ◽

Teresa Sinnwell ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Arterial Blood ◽

Radioactive Microsphere ◽

Low Concentrations ◽

Cat Brain ◽

Nmr Techniques ◽

High Concentrations ◽

Washout Curves ◽

The Brain

19F NMR was used to determine washout curves of an inert, diffusible gas (CHF3) from the cat brain. The cerebral blood flow was estimated from a bi- or tri-phasic fit to the deconvoluted wash-out curve, using the Kety-Schmidt approach. Cerebral blood flow values determined by 19F NMR show the expected responsiveness to alterations in Paco2, but are approximately 28% lower than cerebral blood flow values determined simultaneously by radioactive microsphere techniques. High concentrations of CHF3 have little effect on intracranial pressure, mean arterial blood pressure or Paco2, but cause small changes in the blood flow to certain regions of the brain. We conclude that 19F NMR techniques utilizing low concentrations of CHF3 have potential for the noninvasive measurement of cerebral blood flow.

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