1. An imaging system that allows for modification of data acquisition parameters, where the parameters affect dose distribution, comprising: a library of exams, wherein the library of exams comprises a plurality of scans from different patients; and a computer programmed to: obtain a set of scanning parameters for image data acquisition and image reconstruction; select a scan from among the plurality of scans from the library of exams based on a similarity metric for a patient to be scanned and obtain scan data from the scan; simulate a new scan of the patient using the obtained scan data and using the obtained set of scanning parameters; and generate a new set of scanning parameters based on the simulation.