Reliability and Accuracy of Peri-Interventional Stenosis Grading in Peripheral Artery Disease Using Color-Coded Quantitative Fluoroscopy: A Phantom Study Comparing a Clinical and Scientific Postprocessing Software

Table 2

Results of the ANOVA analysis for ROIs II to IV as assessed with iFlow. Percentage changes of contrast intensity curves (area under the curve) using four different integration times (1, 3, 5, and 7 seconds) are compared to a reference ROI 5 cm proximal to the stenosis (ROI I). Arithmetic mean, standard deviations, and p values (significant values are marked with an asterisk) of three repeated measurements are listed.

ROI	Integration times [seconds]	0% stenosis	40 % stenosis	60 % stenosis	80 % stenosis	p-value
II
	1s	-18.67% (±17.67%)	-6% (±9.72%)	5.33% (±4.51%)	-47% (±44.19%)	0.1264
	3s	6.67% (±3.21%)	11% (±10.54%)	7.67% (±3.06%)	-10% (±18.52)	0.1608
	5s	12.67% (±2.31)	6.33% (±2.52%)	10% (±4.36%)	-13% (±12.66%)	0.0061
	7s	15% (±3%)	5% (±1.73%)	9% (±4.36%)	-17.67% (±11.68%)	0.0013
III
	1s	-28.67% (±30.62%)	-5.33% (±6.11%)	-11% (±11.79%)	-65.67% (±39.5)	0.0474
	3s	8% (±9.64%)	19.67% (±26.39%)	12% (±4.58%)	3.33% (±17.9%)	0.5835
	5s	18.67% (±6.65%)	11% (±8.66%)	12.67% (±4.51%)	-0.67% (±12.1%)	0.02
	7s	23.33% (±5.77%)	5.33% (±8.39%)	10.33% (±4.04%)	-15.67% (±9.45%)	0.0012
IV
	1s	-73.33% (±19.63%)	-13.67% (±18.9%)	-4% (±11.53%)	-78.33% (±31.47%)	0.0048
	3s	-23.67 % (±8.14%)	26.67% (±42.4%)	12.33% (±13.8%)	5.33% (±13.3%)	0.1422
	5s	-3.67% (±5.51%)	22.33% (±31.01%)	15% (±15.13%)	1.67% (±11.93%)	0.3526
	7s	4.33% (±4.93%)	16% (±28.51%)	13% (±13.45%)	-5.67% (±9.71%)	0.4322