xSPECT derived absolute and relative SUV: Efficient tools for I-123-ioflupane analysis

Aim: Quantification of I-123-Ioflupane uptake within basal ganglia using the latest SPECT scanners may add valuable accuracy in the diagnosis of neurodegenerative diseases of the nigro-striatal pathway. We investigated the role of absolute and relative SUV quantification of I-123-Ioflupane in differentiating between normal and pathologic patients. Materials & Methods: In total, 35 individuals were scanned (Symbia Intevo, Siemens Healthcare) and images were reconstructed using conventional iterative reconstruction (Flash-3D) and the xSPECT algorithm providing absolute SUV values. Nine were scored as normal on visual rating and relative metric methods (SSSA based on Flash-3D) and twenty-six as abnormal. Data were analyzed using Scenium (sngo.Via, Siemens Healthcare), which coregisters individual tomographic data to a reference template and subsequently applies a standard set of volumes of interest (VOI), automatically extracting mean regional counts and SUV values for the left and right caudate nucleus, putamen and striatum, as well as for the occipital region (reference region for the calculation of the relative SUV or rSUV). We compared SUVmean, SUVmax and rSUV in normal and abnormal subgroups for each region of interest, as well the uptake asymmetry. Results: Absolute SUVmax and rSUV allowed to differentiate between normal and pathological DATscan in the caudate nucleus (p=0.008 and p=0.003), putamen (p