Plasma L-[18F]6-fluorodopa input function: a simplified method.

G L Chan; K S Morrison; J E Holden; T J Ruth

doi:10.1038/jcbfm.1992.121

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Plasma L-[18F]6-fluorodopa input function: a simplified method.

G L Chan·K S Morrison·J E Holden·T J Ruth

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Abstract

This article describes a simplified method for the determination of the L-[18F]6-fluorodopa (FDOPA) fraction time course that takes advantage of the strong correlation between the radioactivity ratio (metabolites/FDOPA) and time. Serial arterial blood samples are collected for assay of plasma total radioactivities following an intravenous injection of FDOPA into carbidopapretreated subjects. In addition, a single plasma sample, collected late in the study and analyzed for FDOPA fraction, is sufficient to determine accurately the time course of the FDOPA concentration in plasma. The validated straight-line method greatly simplifies blood analysis for routine positron emission tomography FDOPA studies.

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Dihydroxyphenylalanine Fluorine Radioisotopes Humans Regression Analysis Time Factors Tomography, Emission-Computed Journal Article Research Support, Non-U.S. Gov't

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G L Chan, K S Morrison, J E Holden, T J Ruth. 1992. Plasma L-[18F]6-fluorodopa input function: a simplified method.. https://doi.org/10.1038/jcbfm.1992.121

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