asl2p: Kinetic Models for Arterial Spin Labeling

Description Usage Arguments Value Author(s) References Examples

View source: R/asl_models.R

Description

Theoretical models for the acquisition of pulsed ASL data.

See Buxton etal. (1998) for more details.

Usage

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asl2p(beta, TI, T1b = 1.3, T1 = 1, tau = 1, alpha = 0.9, lambda = 0.9,
  Mob = 4095)

asl3p(beta, TI, T1b = 1.3, T1 = 1, alpha = 0.9, lambda = 0.9,
  Mob = 100)

Arguments

beta

is a vector (lenth = 2 or 3) of kinetic parameters.

TI

is a vector of inversion times (TIs) in seconds.

T1b

is the longitudinal relaxation time of blood.

T1

is the longitudinal relaxation time of tissue.

tau

is the first TI in the second paper (?).

alpha

is the fraction of maximum possible change in the longitudinal magnetization that was achieved.

lambda

is the equilibrium tissue/blood partition coefficient of water.

Mob

is the equilibrium magnetization of arterial blood.

Value

A theoretical curve of pulsed ASL signal as a function of time.

Author(s)

Brandon Whitcher bjw34032@users.sourceforge.net

References

Buxton, R.B., Frank, L.R., Wong, E.C., Siewert, B., Warach, S. and Edelman, R.R. (1998) A General Kinetic Model for Quantitative Perfusion Imaging with Arterial Spin Labeling, Magnetic Resonance in Medicine, 40, 383-396.

Examples

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TI <- seq(0, 3, length=256)
beta <- c(f=0.8, deltaT=0.5)
plot(TI, asl2p(beta, TI), type="l", lwd=2,
     xlab="Time (sec)", ylab="Signal", main="Pulsed ASL: Standard Model")
abline(v=1.5, lwd=2, col=2)

neuroconductor/oro.asl documentation built on May 19, 2021, 5:25 a.m.