Regularize SVD (deconvolution) solution of cerebral blood flow.

Ostergaard's regularization approach for a model independent solution of cerebral blood flow using a blood pool contrast agent (http://www.ncbi.nlm.nih.gov/pubmed/8916023).

deconvolutionSVD(arterialInputFunction, thresholdSVD = 0.2)

Arguments

arterialInputFunction

vector specifying the arterial input function over time.

thresholdSVD

is used to threshold the smaller elements of the diagonal matrix during the SVD regularization. 0.2 is a common choice (cf. page 571, end of column 2 in http://www.ncbi.nlm.nih.gov/pubmed/16971140).

Value

regularized residue function, i.e. the right-hand side of CBF * dT * R = ( V * L^-1 * U^T ) * Cvoi.

Author

Tustison NJ

Examples

S0aif <- 17.62
Saif <- c(
  16.25, 16.37, 20.22, 78.96, 230.5, 249.79, 198.58, 147.76,
  110.39, 111.64, 129.43
)
Caif <- -log(Saif / S0aif)

dSVD <- deconvolutionSVD(Caif, 0.2)