Experimental measurement of Modulation Transfer Function (MTF) in five commercial CT scanners

Abstract

The modulation transfer function (MTF) is the technical description of spatial resolution for most imaging systems. the MTF describes how well an imaging system processes signal [1,4]. There are several methods for calculation of MTF that can be categorized in theoretical and experimental methods. In this study, in order to compare the performance of five different commercial CT scanner, an experimental method was used to calculate MTF in all scanners. The MTF curves were calculated for both axial and helical scanning mode and also for different slice thickness. The method for experimental measurement of MTF which called SD method is based on calculation of the standard deviation (SD) of CT numbers in different regions of scanned phantom and determination of coefficient modulation. The results calculated in this study using simple experimental measurements were in good agreement with published technical specification by manufacturers [5]. © 2010 International Federation for Medical and Biological Engineering.