TABLE 1

Kinetic Modeling of Striatum^*

Parameter	2C-3p	3C-5p	3C-5p	3C-4p with k₄ = 0	Patlak-2p	Logan-2p
Metabolite correction	No	No	Yes	Yes	No	No
k₁	0.108 ± 0.023	0.163 ± 0.044	0.124 ± 0.034	0.088 ± 0.020
k₂	0.052 ± 0.007	0.165 ± 0.072	0.199 ± 0.084	0.084 ± 0.024		0.047 ± 0.007
k₃		0.029 ± 0.017	0.075 ± 0.019	0.034 ± 0.004
k₄		0.014 ± 0.011	0.010 ± 0.004
K		0.023 ± 0.009	0.034 ± 0.008	0.025 ± 0.005	0.015 ± 0.003
V_b	0.01 ± 0.01	0.14 ± 0.05	0.10 ± 0.03	0.12 ± 0.03
V_ed	2.09 ± 0.41	1.10 ± 0.39	0.69 ± 0.23	1.12 ± 0.36	1.28 ± 0.26	1.61 ± 0.31
WRSS	1,811 ± 823	178 ± 137	150 ± 98	229 ± 128
n (P < 0.05)	Reference	45	45	45

↵* Estimates of fitted parameters k₁–k₄, influx rate constant K, blood volume fraction in tissue (V_b), and equilibrium distribution volume (V_ed) were determined. Results are expressed as mean ± SD for 45 studies in 37 patients. Partial-volume correction was applied. Input function was corrected for metabolites as indicated. Error estimate WRSS was measure of goodness of fit between measured and calculated output functions. Graphical analysis with Patlak and Logan plots was applied to images obtained between 15 and 75 min. n (P < 0.05) denotes number of studies with significantly lower error than 2C-3p (reference), as determined by F test.
2C = 2-compartment model; 3p = 3 parameters; 3C = 3-compartment model; 5p = 5 parameters; 4p = 4 parameters; 2p = 2 parameters.