Table 1.

Summary of the acquisition and patient preparation parameters for the local and PPMI databases

Parameter	Local database	PPMI database
Administered activity	167–185 MBq	111–185 MBq
Injection-to-scan delay	3–6 h	3.5–4.5 h
Acquisition time	30 min	30–45 min
Acquisition pixel size	3.68 mm	Variable (scanner dependent)
Number of projections	120 (over 360°)	90 or 120 (over 360°)
Energy window	159 keV ± 10%	159 keV ± 10% and 122 keV ± 10%
Collimator	LEHR	Variable (scanner dependent)