TABLE 1

Commonly Used Parameters from Dynamic Planar ^99mTc-GSA Scintigraphy

Abbreviation	Parameter	Description	Mathematic formula	Application
LHL15	Hepatic uptake ratio of ^99mTc-GSA	Liver counts at 15 min (L15) divided by heart counts (H15) plus L15	$\text{[math]}$	Total liver function and regional liver function
HH15	Blood clearance ratio	Heart counts at 15 min (H15) divided by heart counts at 3 min (H3)	$\text{[math]}$	Total liver function
MRI	Modified receptor index	LHL15 divided by HH15	$\text{[math]}$	Total liver function
K_L	Blood clearance constant	Calculated from liver uptake curve, with clearance half-time (T_1/2) (Fig.1)	$\text{[math]}$	Total liver function
			$\text{[math]}$
LU15	Liver uptake	Cumulative liver uptake 15–16 min after injection from liver time–activity curve (L(t))	$\text{[math]}$	Total liver function
LHL15-V	Ratio of liver uptake to liver volume (mL)	Liver uptake ratio (LHL15) divided by total liver volume	$\text{[math]}$	Total liver function
R_max	Maximal removal rate of ^99mTc-GSA	Calculated with kinetic model of Ha-Kawa et al. (36)	Requires multiple equations	Total liver function
R₀	Asialoglycoprotein receptor concentration	Calculated with kinetic model of Vera et al. (37)	Requires multiple equations	Total liver function