1. A method for estimating parameter values comprising: obtaining image data with an imaging apparatus; fitting a parameterized model function utilized to estimate myocardial blood flow and representing spillover by a scaling factor [ f v ( 1 - f v ) ⁢ K 1 ] where f v is a spillover fraction and K 1 is an influx value from the image data by: generating a N-dimensional grid, wherein N is a number of one or more terms that are non-linear in a parameter of the derived model function; pre-calculating the one or more non-linear terms given the parameter model function and the designated values of the non-linear parameters; calculating one or more remaining model terms of the parameter model function; and displaying at least one of the one or more non-linear and remaining linear model terms.