Impacts of acquisition and reconstruction parameters on the absolute technetium quantification of the cadmium–zinc–telluride-based SPECT/CT system: a phantom study

EJNMMI Physics

Table 4 Comparison of COVs (Coefficients of variation, %) of all spheres among three different correction combinations

	Correction combination	37 mm	28 mm	22 mm	17 mm	13 mm	10 mm	P value
32:1	AC + SC + RR	93.77	92.21	88.01	87.85	85.95	86.64
	AC + RR	74.53	72.91	70.50	71.00	69.76	70.82	< 0.001^a
	AC + SC	102.96	103.52	101.71	101.53	100.70	100.80	< 0.001^b
16:1	AC + SC + RR	95.09	94.61	89.02	89.62	88.86	85.71
	AC + RR	76.36	75.60	72.28	72.54	70.40	69.06	< 0.001^a
	AC + SC	96.95	96.33	97.64	97.13	95.44	94.43	0.007^b
8:1	AC + SC + RR	97.25	94.93	91.36	90.93	90.74	87.10
	AC + RR	77.98	75.92	73.78	72.54	72.06	69.67	< 0.001^a
	AC + SC	96.31	93.75	94.79	94.89	95.34	95.60	0.096^b
4:1	AC + SC + RR	92.71	88.97	84.03	83.13	82.02	79.55
	AC + RR	73.12	72.69	69.53	68.38	66.97	64.92	< 0.001^a
	AC + SC	91.77	91.38	91.91	91.49	91.80	94.04	0.026^b

Reconstruction parameters: 35 iterations, 20 subsets, no filter; Acquisition parameters: 120 s/frame of acquisition time, 15% energy window; AC, attenuation correction; SC, scatter correction; RR, resolution recovery correction; a, AC + SC + RR vs. AC + RR; b, AC + SC + RR vs. AC + SC