The Effect of Tissue Erosions and Segmentation Probability Thresholds on Magnetisation Transfer Ratio Histograms

Daniel J. Tozer¹, Sameeha Fallatah¹, Leonora Finisku¹, David H. Miller¹

Magnetisation transfer ratio histograms are widely used in the study of multiple sclerosis. Histogram generation methods may affect the parameters extracted. This work investigates whether the tissue probability threshold used in segmentation and the number of erosions applied to the tissue segments effect the histogram parameters and whether this differs between healthy controls and multiple sclerosis patients. It is found that the number of erosions has more of an effect on the histogram parameters than the probability threshold used, in particular the first erosion. There were some differences between the behaviour in patients and controls, but this was not systematic.