The assessment of physical image quality in diagnostic radiology is a well established discipline. It has evolved over several decades and is based on the measurement of three fundamental parameters: contrast, spatial resolution and noise. Image transfer theory has been successfully applied to determine signal and noise transfer characteristics to a known input. Metrics of image and system quality includes modulation transfer function (MTF), noise-equivalent number of quanta (NEQ), and detective quantum efficiency (DQE) among others. Furthermore, to facilitate a comparison of detector systems and to obtain an overall view of their performance, quality indices have been also introduced. Pertinent physical quantities will be critically reviewed and discussed in the framework of the digital technology. Finally, it is important to bear in mind that extrapolation from objective measures of image quality to performance in the clinical situation is always problematical due to the complexity of the diagnostic task. A complete evaluation of imaging system performance requires a psychophysical approach in order to take the observer's behaviour into account.
Evaluation of the quality of radiological systems using objective measurements
TAIBI, Angelo
2008
Abstract
The assessment of physical image quality in diagnostic radiology is a well established discipline. It has evolved over several decades and is based on the measurement of three fundamental parameters: contrast, spatial resolution and noise. Image transfer theory has been successfully applied to determine signal and noise transfer characteristics to a known input. Metrics of image and system quality includes modulation transfer function (MTF), noise-equivalent number of quanta (NEQ), and detective quantum efficiency (DQE) among others. Furthermore, to facilitate a comparison of detector systems and to obtain an overall view of their performance, quality indices have been also introduced. Pertinent physical quantities will be critically reviewed and discussed in the framework of the digital technology. Finally, it is important to bear in mind that extrapolation from objective measures of image quality to performance in the clinical situation is always problematical due to the complexity of the diagnostic task. A complete evaluation of imaging system performance requires a psychophysical approach in order to take the observer's behaviour into account.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.