Table 3

The mean annual rate of progression and estimates of preclinical period according to each method of PET analysis and method of extrapolation in this group of 32 patients

Structure (method of analysis)Annual rate of progressionEstimated duration of preclinical period (y)
AbsoluteNormal mean (%)Baseline mean (%)Method AMethod B
Putamen (Ki)0.00048 (0.0009) years 6.5 years
Caudate (Ki)0.00032 (0.0015) years 4.2 years
Total striatum (Ki)0.00029 (0.0005) years 3.3 years
Putamen (ratio)0.050 (0.14) years 9.5 years
Caudate (ratio)0.0089 (0.16) years37.2 years
  • Values in parentheses are SD.