A Post-market, Multi-vessel Evaluation of the Imaging of Peripheral Arteries for Diagnostic Purposes Comparing Optical Coherence Tomography and Intravascular Ultrasound Imaging (SCAN)

Background: Intravascular imaging plays an important part in diagnosis of vascular conditions and providing insight for treatment strategy. Two main imaging modalities are intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The objective of this study was to prove non-inferiority of OCT imaging to IVUS images in matched segments of peripheral vessels in patients with suspected peripheral vascular disease. Methods: The SCAN study was a prospective, non-inferiority clinical study of matched IVUS and OCT images collected along defined segments of peripheral vessels from twelve subjects (mean age 68 10.3 years; 10 men) displaying symptoms of vascular disease. Luminal diameters were measured by both imaging systems at the distal, middle, and proximal points of the defined segments. Three blinded interventional radiologists evaluated the quality of both imaging modalities in identifying lMann-Whitney-Wilcoxon testing. Intrareader reproducibility was calculated by intraclass correlation (ICC) analysis. Results: The mean scoringof plaque, calcification, and vascular stent struts by the three readers was significant better in terms of image quality for OCT than IVUS (p<0.001, p=0.001, p=0.004, respectively). The mean scores of vessel wall component visibility and artifacts generated by the two imaging systems were not significantly different (p=0.19, p=0.07, respectively). Mean vessel luminal diameter and area at three specific locations within the vessels were not significantly different between the two imaging modalities. No patient injury, adverse effect or device malfunction were noted during thestudy. Conclusions: Imaging byOCT provides the physician with better visualization of some vessel and plaque chacteristics, but both IVUS and OCT imaging are safe and effective methods of examining peripheral vessels in order to perform diagnostic assessment of peripheral vessels and provide information necessary for the treatment strategy of peripheral artery disease.