Photon-counting computed tomography enables low-dose, high-quality abdominal imaging: A comparative study with energy-integrating detector computed tomography

Table 4 Comparison of objective and subjective image quality parameters between abdominal photon-counting computed tomography and energy-integrating detector computed tomography, median (interquartile range)

Variable	PCCT	EID-CT	P value
meanliver	65.95 (62.60-68.80)	61.35 (55.77-65.08)	0.001
SDliver	11.60 (10.85-12.45)	18.60 (16.62-20.32)	< 0.001
meanfat	-108.35 (-111.72 to -103.78)	-106.15 (-110.78 to -99.08)	0.192
SDfat	11.75 (11.00-12.50)	14.30 (13.03-16.35)	< 0.001
SNR	5.57 (5.02-6.32)	3.26 (2.71-3.76)	< 0.001
CNR	10.26 (9.76-11.36)	7.14 (6.21-7.67)	< 0.001
EII	71.99 (52.96-93.39)	17.38 (12.71-20.75)	< 0.001
SNR/(CDTI)1/2	2.90 (2.46-3.53)	1.21 (0.97-1.47)	< 0.001
CNR/(CDTI)1/2	5.46 (4.77-6.36)	2.62 (2.36-2.98)	< 0.001
NR	1.00 (0.94-1.05)	1.29 (1.10-1.48)	< 0.001
Likert			< 0.001
3	1	29
4	8	7
5	31	4

EID-CT: Energy-integrating detector computed tomography; PCCT: Photon-counting computed tomography; SNR: Signal-to-noise ratio; CNR: Contrast-to-noise ratio; EII: Excellent image index; CDTI: Computed tomography dose index; NR: Noise ratio.