lortie.fit: Lortie et al. (2007) model fit.

Description Usage Arguments Value

View source: R/model-lortie.R

Description

Fits the one-tissue compatment 82-rubidium model implemented in lortie.model.

Usage

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  lortie.fit(input.function, tissue, time.start, time.end,
    a = 0.77, b = 0.63, FLV.start = 0.1, FLV.lower = 0,
    FLV.upper = 1, flow.start = 0.5, flow.lower = 0,
    flow.upper = 8, k2.start = 0.1, k2.lower = 0,
    k2.upper = 8, left.ventricle = input.function,
    weight = time.end - time.start, plot = FALSE,
    interpolation.type = 1, ...)

Arguments

input.function

Input function TAC (typically, left ventricle).

tissue

Tissue (myocardium) TAC.

time.start

Initial time for each frame (in minutes).

time.end

End time for each frame (in minutes).

a

Parameter a of the Renkin-Crone equation implemented in flow2k1. Defaults to 0.77 [unitless].

b

Parameter b of the Renkin-Crone equation implemented in flow2k1. Defaults to 0.63 [ml/min/g].

FLV.start,flow.start,k2.start

Initial parameter values for the non-linear squares fitting.

FLV.lower,flow.lower,k2.lower

Lower bounds.

FLV.upper,flow.upper,k2.upper

Upper bounds.

left.ventricle

Left ventricle TAC, used for spill-over corretion. Defaults to input.function.

weight

Weights for the non-linear least squares. Defaults to frame length.

plot

Should the results be plotted. Defaults to FALSE.

interpolation.type

Interpolation type selection. Passed to interpolate.tac. Defaults to 1.

...

If plotting is used, optional parameters are passed to the plot function.

Value

Returns a list with three fields: kparms, the computed kinetic parameters; stderrors, the standard errors for each parameter as a percentage; fit, the actual fitted object.


traceRkinetic documentation built on May 31, 2017, 4:36 a.m.