Fig. 3.

Results of Mean Cortical Index of SUVR in patients suspected of having dementia and related diseases. Each group represents a patient group with various disease, A: AD in moderate stage, B: AD in early stage, C: Healthy volunteers (49 years old and younger), D: Healthy volunteers (50 years old and older), E: Other dementia (including Dementia with DLB, PART, FTD, iNPH, corticodegeneration and unknown), and E: Mild Cognitive impairment (MCI). Mean Cortical Index of AD patients in moderate stage (1.342 ± 0.191) and early stage (1.288 ± 0.134) were significantly higher than those of healthy volunteers in both age range (50 years old and older and 49 years old and younger). Based on the regression line in Fig. 4a (dotted line), we determined that Mean Cortical Index of 1.2 in [18F]FPYBF-2, which corresponds to the widely accepted threshold of 1.5 for PiB, can be used as a threshold value between normal and dementia. Please find Fig. 4