Feasibility of utilizing ultra-low-dose contrast medium for pancreatic artery depiction using the combination of advanced virtual monoenergetic imaging and high-concentration contrast medium: an intra-patient study

Insights into Imaging

Table 2 Results of quantitative analysis

Parameters	ND-CM images*	LD-CM images*	LD-CM VMI+ images*	p₁ value^†	p₂ value^†	p₃ value^†
Average value (HU)
Aorta	337.8 ± 55.36	260.16 ± 73.08	1029.76 (735.08 ,1223.75)	< 0.0001	< 0.0001	< 0.0001
Celiac artery	343.42 ± 56.01	285.32 (213.88, 325.31)	1078.28 (817.35, 1219.92)	< 0.0001	< 0.0001	< 0.0001
SMA	346.65 ± 60.24	285.27 (211.30, 336.15)	1034.77 (713.07, 1227.04)	< 0.0001	< 0.0001	< 0.0001
Right Erector spinae muscles	53.76 ± 6.26	53.68 ± 4.98	66.79 ± 10.60	0.3471	< 0.0001	< 0.0001
Image noise (HU)
Right Erector spinae muscles	19.99 ± 3.67	19.79 ± 3.33	44.15 ± 9.41	0.5136	< 0.0001	< 0.0001
Signal to noise ratio (SNR)
Aorta	13.38 ± 2.92	10.38 ± 2.64	12.06 ± 3.29	< 0.0001**	0.0465**	0.0113**
Celiac artery	15.27 ± 4.10	11.94 ± 3.64	13.67 (10.27, 15.27)	< 0.0001	0.6911	< 0.0001
SMA	15.1 ± 3.45	11.58 ± 3.55	14.25 ± 5.09	< 0.0001	1.0000	< 0.0001
Contrast to noise ratio (CNR)
Aorta	14.57 ± 3.64	10.46 ± 3.81	20.71 ± 7.30	< 0.0001	< 0.0001	< 0.0001
Celiac artery	14.86 ± 3.71	10.85 ± 4.00	21.23 ± 7.17	< 0.0001	< 0.0001	< 0.0001
SMA	15.03 ± 3.94	10.86 ± 4.06	21.00 ± 7.30	< 0.0001	< 0.0001	< 0.0001

Data are means ± standard deviations or Median (P25, P75)
*ND-CM: normal dose contrast medium (320 mgI/kg), LD-CM: low dose contrast medium (224 mgI/kg), VMI+ LD-CM images: advanced virtual monoenergetic imaging of LD-CM images
**p value was calculated by R
^†P₁: the difference between ND-CM images and LD-CM images; P₂: the difference between ND-CM images and VMI+ LD-CM images; P₃: the difference between LD-CM images and VMI+ LD-CM images by using the randomized block ANOVA analysis or Friedman test. p < 0.05 is considered statistically significant