Table 3.

Comparison of spectral CT quantitative parameters between different Ki-67 expression levels in NSCLC.

Parameters	Low level	High level	P value
70 keV CT value in AP	45.83 ± 17.54	40.25 ± 16.71	0.209
70 keV CT value in VP	64.63 ± 18.34	52.40 ± 16.04	0.008
NIC in AP	0.18 ± 0.08	0.12 ± 0.04	<0.001
NIC in VP	0.47 ± 0.11	0.33 ± 0.07	<0.001
λHU in AP	2.02 ± 0.93	1.34 ± 0.42	<0.001
λHU in VP	2.81 ± 0.87	1.76 ± 0.32	<0.001

keV, kilo electron volt; NIC, normalized iodine concentration; λ_HU, the slope of the spectral curve. AP, arterial phase; VP, venous phase.