Table 1.

Tracer Kinetic Renal Models

Model	Compartments			Input data	No of parameters
	No	Vascular	Tubular
Baumann-Rudin (BR) (11,12)	1	ND	I	Cx and Med	1
Patlak-Rutland (PR) (13–15)	2	ND	I	Ao and K (or Cx)	2
2C (15)	2	ND	IO	Ao and K (or Cx)	3
2CD (14)	2	D	IO	Ao and K (or Cx)	5
3CD (16)	3	D	IO	Ao, Cx, and Med	6
3C-IRF (17)	3	D	I-IO	Ao, Cx, and Med	7*

2C and 3C, two- and three-compartment models; IRF, impulse residue function-based model; ND, no dispersion; D, dispersion; I, inflow; IO, inflow and outflow; I-IO, inflow only followed by inflow-outflow; Ao, aorta; Cx, cortex; Med, medulla; K, whole kidney parenchyma.

^*In 3C-IRF model (17), the number of adjustable parameters was reduced from 9 to 7, by fixing two parameters.