About the background distribution in MR data: a local variance study.
A model for the distribution of the sample local variance (SLV) of magnetic resonance data is proposed. It is based on a bimodal Gamma distribution, whose maxima are related to the signal and background areas of the image. The model is valid for single- and multiple-coil systems. The proposed distribution allows us to characterize some signal/background properties in MR data. As an example, the model is used to study the effect of the background size over noise estimation techniques and a method to test the validity of background-based noise estimators is presented.
Aja-Fernández
Santiago
S
LPI, ETSI Telecomunicacion, Universidad de Valladolid, Valladolid, Spain. sanaja@tel.uva.es
Vegas-Sánchez-Ferrero
Gonzalo
G
Tristán-Vega
Antonio
A
D000704:Analysis of Variance; D001921:Brain / Q000033:anatomy & histology*; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008954:Models, Biological; D015233:Models, Statistical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016008:Statistical Distributions