Semiqunatitative analysis using standardized uptake value in ¹²³I-FP-CIT SPECT/CT

Objectives: To evaluate utility of standardized uptake value (SUV) in ¹²³I-FP-CIT SPECT/CT compared to specific binding ratio (SBR).

Methods: 36 patients (18 male, 18 female, mean age of 74.1 years old) were enrolled in this retrospective study. Study cohort included 20 Parkinson disease (PD), 8 dementia with Lewy body (DLB), 1 progressive supranuclear palsy (PSP), 4 essential tremor, and 3 Alzheimer disease. Mean SBR, maximum SUV (SUVmax), and peak SUV (SUVpeak) of bilateral basal ganglia were calculated in all patients using VirtualPlaceHayabusa (AZE, Japan) and GI-BONE (AZE, Japan). Pearson's correlation coefficient was used to evaluate correlation between SBR and SUV. We evaluated differential diagnostic ability of SBR and SUV using the cutoff value calculated from receiver operating characteristic curve analysis.

Results: SBR showed statistically significant correlation with SUVmax (R=0.773) and SUVpeak (R=0.776). For differential diagnosis of PD, DLB, and PSP, sensitivity, specificity and accuracy of SBR were 89.7%, 85.7%, and 88.9%, respectively (cutoff SBR=4.72). SUV showed lower diagnostic ability compared to SBR (sensitivity of 75.9%, specificity of 100%, and accuracy of 80.6% using cutoff SUVmax=12.33).

Conclusion: Although there is statistically significant correlation between SBR and SUV, SUV is inferior to SBR in differential diagnosis. Research Support: None.