Fig. 6

Divergent quantitative diagnosis based on method of quantification. Patient studies with divergent quantitative diagnosis based on the quantification method used. a Two consecutive slices from a study of a 73-year-old male patient with a working diagnosis of a dopaminergic degenerative disorder (Lewy body dementia) are found to be abnormal using all BRASS quantification and rated normal in all but the calibrated ACSC reconstruction using Southampton quantification. b A clinically abnormal study of a 65-year-old female patient with a 3-year follow-up diagnosis of a dopaminergic degenerative disorder (multiple system atrophy) which was normal using BRASS quantification with the exception of striatal and putaminal binding ratios using a calibrated FBP approach (and putamen non-calibrated) and rated abnormal with the Southampton method of quantification. c The different assessment regions used. On the left is one slice of several highlighting tight BRASS striatal regions of interest over the caudate and putamen in addition to the occipital lobe reference region. Right, the Southampton method is applied to summed striatal slices with large VOIs to account for partial volume effects with the reference region encompassing all other brain pixels