Introduction: Intravascular ultrasound (IVUS) provides real-time imaging of aortic pathology during aortic interventions. The objective of the present study was to validate IVUS measurements using computed tomography (CT) angiography in a sufficiently large cohort.
Material and methods: From October 2010 to February 2014, 57 consecutive patients with acute aortic syndrome underwent both IVUS and spiral CT for a total of 509 comparable thoracic aorta segments. Minimum, maximum, and mean diameters were determined at each measurement point.
Results: IVUS measurements of the thoracic aorta (aortic root, brachiocephalic trunk, left common carotid artery, left subclavian artery) ranged from 18-48.5 (mean 33.0) mm, versus 18-48.4 (mean 31.7) mm on CT, with a significant mean difference of 5.1% (p < 0.05). The correlation between methods was generally good, but IVUS tended toward larger diameters than CT in the aortic arch, especially the left subclavian artery. In 78% of measurement sites, total mean diameters were larger on IVUS measurements of the thoracic aorta than on CT measurements.
Conclusion: IVUS is a reliable tool for measuring aortic diameter, especially in the descending part of the aorta. However, its pitfalls must be considered to prevent choosing an incorrectly sized stent graft in the acute setting of thoracic endovascular aortic repair.
Keywords: IVUS; Intravascular ultrasound; TEVAR; aortic aneurysm; computed tomography; thoracic endovascular aortic repair.