The modulation transfer function. A simplified procedure for computer-aided quality evaluation in mammography

Regardless of the indisputable benefits of the modulation transfer function (MTF) method to radiographic image quality evaluation, most radiologists simply do not have the means for utilizing it due to the experimental difficulties in its application to mammography practice. One of the most significant difficulties for radiological departments is having the necessary equipment to digitize slit radiographic images-a microdensitometer, for example-to be used in quality assurance programs. Therefore, the authors propose the application of the transfer function method for quality evaluation of mammography equipment using a different procedure. This procedure is based on the calculation of the MTF from a simulated line spread function derived from the focal-spot projection. Since this technique does not need digitized images and can be performed on a PC, it will allow the use of the transfer function method in quality control programs without the constraints associated with the complexity of classical experimental procedures.