TABLE 2

Fitting Precision with 2 Types of IF

ParameterK1 (mL/min/cm3)SD (%)k2 (1/min)SD (%)k3 (1/min)SD (%)k4 (1/min)SD (%)KFDG (mL/min/cm3)SD (%)
IDIF 10.29610.3830.76617.0560.12511.8050.02413.2320.0415.837
IDIF 20.2696.9670.90710.7660.1019.5820.02911.6260.0275.749
IDIF 30.2387.2910.73112.5450.10712.1060.02317.6100.0316.845
IDIF 40.4686.7460.92010.2730.1018.9880.01917.1810.0465.454
IDIF 50.4025.7260.7369.4550.1316.7170.0276.8760.0613.297
Shunt 10.2941.4500.6532.0130.1053.4970.0227.9800.0412.449
Shunt 20.1621.2450.4301.9370.0644.8540.02011.5870.0213.311
Shunt 30.2261.0160.6141.4050.0803.5150.0179.3840.0262.515
Shunt 40.2840.5730.4820.7990.0671.8380.0128.4760.0351.379
Shunt 50.4071.0720.6560.9450.1022.3970.0224.3540.0551.331
σ2IDIF > σ2shuntdfFFFFF
 Mouse 126/2652.041*98.696*16.142*3.5175.918*
 Mouse 229/2986.185*137.309*9.716*2.1364.975*
 Mouse 327/2757.444*112.981*21.159*6.656*10.104*
 Mouse 429/29377.026*603.740*53.824*9.845*27.648*
 Mouse 530/3027.875*125.813*12.774*3.7677.475*
  • Original data from C57BL/6 mice used in this study. F tests revealed significantly (*P < 0.01, corrected for multiple comparisons, with df depending on number of image frames in respective PET dataset) larger variances in fitted parameters using IDIF than using shunt IF. Pattern was similar in CD1 mice, for which K1 and k2 could be estimated with significantly (P < 0.01) higher precision in all animals, and k3, k4, and KFDG in 6, 3, and 4 of 8 animals, respectively.