A gamma-distribution convolution model of 99mTc-MIBI thyroid time-activity curves

EJNMMI Physics

Table 3 Poisson noise simulations and accuracy of recovery of generating parameters following regression

Parameters	t _A	a	b	α	β	S ^a	MRT_WO
Units	min	none	min⁻¹	none	min⁻¹	10⁶ counts	min
Clinical mean values	0.316	3.013	4.223	0.8863	0.00276	4.335	367.4
Simulation mean values^b	0.316	3.314	4.588	0.8859	0.00275	4.342	369.1
Units	Percentage (%)
Mean simulation CV error^c	2.4	0.23	1.6	0.26	3.1	2.6	0.69
Absolute error in percent^d	0.035	10.0	8.6	−0.038	−0.38	0.15	0.46
Units	Probability
Probability of no difference^e	0.98	0.44	0.52	0.32	0.38	0.73	0.51

^aThe scale factors S, used to scale GDC, are the total counts collected in the ROI from time is zero to infinity
^bEach set of clinical parameters for 9 cases was used to generate 10 different noisy data sets. The simulation mean values are from all 90 simulations
^cThis is the mean value of 9 coefficients of variation (CV), where each CV is from 10 simulations
^dError is 100 times mean simulation minus clinical values divided by mean clinical value time
^eNo significant differences to the 0.05 level from two-tailed t tests for zero difference between 9 paired samples using mean values of 10 simulations for each clinical result and the clinical parameter results themselves