Table 3. Dual-energy Spectral CT parameters of the lymph node metastasis group, non-metastasis group and primary lesions.

Group	IC (mg/mL)	NIC	Spectral curve slope (λHU)
Metastatic	3.93±1.58	0.70±0.55	4.63±1.91
Non-metastatic	1.77±0.71	0.29±0.16	2.19±0.91
Primary lesion	3.03±1.34	0.46±0.18	3.58±1.58
ta	10.866	6.700	9.917
Pa	<0.001	<0.001	<0.001

^a, stands for t-test between metastasis group and non-metastasis group. IC, iodine concentration; NIC, normalized iodine concentration.