Intensity normalization of FP-CIT SPECT in patients with Parkinsonism using the α-stable distribution

In this work, a procedure to perform the normalization of the intensity values in FP-CIT SPECT images for the diagnosis of Parkinson´s disease is presented. The proposed methodology is based on the fact that the shape of the distribution of intensity values is skewed and heavy-tailed, and therefore, it can be modelled in a parsimonious way using the alpha-stable distribution. We have proved that using this procedure we are able to obtain brain images with very similar intensity distribution. Furthermore, we measured the group separation using the t-test and, after normalization, the intensity values in the striatum are more separated than before normalization. Therefore, we believe this intensity normalization procedure enhances the ability of the images to be used to diagnosis the Parkinson´s disease.