Inhalation regional cerebral blood flow: the use of tidal CO/sub 2/ data to find radionuclide activity associated with exhaled alveolar gas

Journal Article · Tue Nov 01 04:00:00 EST 1988 · Med. Phys.; (United States)

DOI:https://doi.org/10.1118/1.596290· OSTI ID:6099682

Allison, J D; 4, Kingsbury TB; Sullivan, H G; Goode, J J

When calculating cerebral blood flow by the inhalation regional cerebral blood flow technique, radionuclide activity associated with exhaled alveolar gas is used to represent the arterial input function for each brain region. In this study, tidal CO/sub 2/ data are used to identify respiratory gas samples that contain alveolar gas. Traditional methods identify alveolar gas samples by searching for maxima and minima in the raw air curve. The raw air curve is determined by sequentially counting radionuclide activity in respiratory gases sampled at the mouth. Traditional methods sometimes erroneously identify and use maxima or minima that do not represent alveolar gas. The use of CO/sub 2/ data is advantageous since the range of CO/sub 2/ during exhalation can identify those exhalations that approach the functional reserve capacity and hence represent alveolar gas. The arterial input function is represented by counting intervals from the raw air curve which coincide with exhalation of alveolar gas as identified by CO/sub 2/ data. This approach for representing the arterial input function is fully automatic, accurate, and reproducible.

• Research Organization: Medical College of Georgia, Augusta (USA)
• OSTI ID: 6099682
• Journal Information: Med. Phys.; (United States), Journal Name: Med. Phys.; (United States) Vol. 15:6; ISSN MPHYA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BLOOD FLOW
BODY
BRAIN
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CENTRAL NERVOUS SYSTEM
CHALCOGENIDES
DYNAMIC FUNCTION STUDIES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MAN
NERVOUS SYSTEM
ORGANS
OXIDES
OXYGEN COMPOUNDS
PRIMATES
RESPIRATION
SPECIFICITY
TRACER TECHNIQUES
VERTEBRATES
XENON ISOTOPES