Utilisation of virtual non-contrast images and virtual mono-energetic images acquired from dual-layer spectral CT for renal cell carcinoma: image quality and radiation dose

Insights into Imaging

Table 3 Qualitative analysis of the image quality and lesion visibility

Group	Reader 1						Reader 2						Kappa value
Score*	1	2	3	4	5	Mean	1	2	3	4	5	Mean	Kappa value
Image quality
TNC images	0	0	0	10	52	4.84	0	0	0	11	51	4.82	0.828
VNC images	0	0	0	13	49	4.79	0	0	0	12	50	4.80	0.850
Lesion visibility
Corticomedullary phase images	0	0	0	20	42	4.68	0	0	0	21	41	4.66	0.891
60kevVMI images	0	0	5	33	24	4.31	0	0	5	34	23	4.29	0.870

*The scores were obtained according to the Likert scale from 1 = unreadable to 5 = excellent