Impact of the arterial input function on microvascularization parameter measurements using dynamic contrast-enhanced ultrasonography

Table 1 Characteristics of the in vivo experiments

Mouse number	Number of days	Number of injections
Multiple injections and day of examination
1	4	3
		4
		3
		4
2	2	3
		2
3	2	2
		4
Influence of the size of the arterial region of interest
1	3	3
		3
		2
2	3	2
		3
		3
3	2	4
		3
4	2	4
		3

Table 2 In vitro and in vivo experiments: Statistical analyses

	In vitro results		In vivo results
	Repositioning of the probe: Fisher’s test P values	Variation of the flow rate: ANOVA P values	Multiple injections: ANOVA P values	Day of examination: ANOVA P values
Semi-quantitative microvascularization parameters
PI	0.077	< 0.001	0.080	< 0.001
TPI	0.302	0.004	0.595	0.641
Slope of the WI	0.059	0.006	0.141	< 0.001
MTT	0.562	< 0.001	0.885	0.016
AUC	0.731	< 0.001	0.073	0.01
AUWI	0.276	0.024	0.060	0.001
AUWO	0.860	0.006	0.078	0.016
Quantitative microvascularization parameters
BF	0.055	0.004	0.071	0.116
BV	0.063	0.053	0.429	0.015
MTT	0.131	0.649	0.126	0.645

ANOVA: Analysis of variance; PI: Peak intensity; T_PI: Time to peak intensity; WI: The wash-in; MTT: The mean transit time; AUC: The area under the curve; AUWI: The area under the wash-in; AUWO: The area under the wash-out; BF: The tissue blood flow; BV: The tissue blood volume.

Table 3 Areas of the arterial region of interests associated with the two in vivo studies described in the article

	Mean (mm2)	SD	Min	Max
First in vivo study	1.17	0.6	0.4	2.3
Second in vivo study	3.65	0.3	3.5	4.1

SD: Standard deviation.

Table 4 Influence of the size of the arterial region of interest (in vivo experiments: Statistical analyses)

	Day of examination : P-ANOVA values
Semi-quantitative microvascularization parameters
PI	0.027
TPI	0.010
Slope of the WI	0.070
MTT	< 0.001
AUC	0.808
AUWI	0.562
AUWO	0.832
Quantitative microvascularization parameters
BF	< 0.001
BV	< 0.001
MTT	0.033

ANOVA: Analysis of variance; PI: Peak intensity; T_PI: Time to peak intensity; MTT: The mean transit time; AUC: The area under the curve; AUWI: The area under the wash-in; AUWO: The area under the wash-out; BF: The tissue blood flow; BV: The tissue blood volume.