Comparability of semiautomatic tortuosity measurements in the carotid artery

• Published in: Neuroradiology Vol. 61; no. 2; pp. 147 - 153
• Main Authors: de Vries, Evelien E., Pourier, Vanessa E. C., van Laarhoven, Constance J. H. C. M., Vonken, Evert J., van Herwaarden, Joost A., de Borst, Gert J.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-02-2019; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Agreements; Angiography; Aortic arch; Bifurcations; Carotid arteries; Carotid Arteries - abnormalities; Carotid Arteries - diagnostic imaging; Carotid artery; Carotid Artery Diseases - diagnostic imaging; Cerebral Angiography - methods; Computed Tomography Angiography - methods; Computer programs; Confidence intervals; Correlation coefficients; Diagnostic Neuroradiology; Female; Humans; Imaging; Male; Mathematical analysis; Measurement techniques; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Neurology; Neuroradiology; Neurosciences; Neurosurgery; Patients; Quantitative analysis; Radiographic Image Interpretation, Computer-Assisted - methods; Radiology; Registries; Reproducibility; Reproducibility of Results; Risk analysis; Risk Factors; Software; Software packages; Tortuosity; Veins & arteries; Software validation; CT angiography; Carotid artery disease; Carotid aneurysm; Quantitative analysis
• ISSN: 0028-3940; 1432-1920
• DOI: 10.1007/s00234-018-2112-3

Purpose
Increased arterial tortuosity has been suggested as a predisposing factor for carotid artery dissection, which is an important risk factor for development of extracranial carotid artery aneurysms (ECAA). Prior to comparison with non-ECAA controls, the optimal measurement technique should be defined. This study describes the difference between software packages in terms of reproducibility and absolute outcome of arterial tortuosity measurements in ECAA patients.
Methods
CT-angiography analysis was performed on 12 ECAA patients selected from our registry, using four software packages: 3mensio Vascular, TeraRecon, Vital Images, and Aycan OsiriX PRO. The tortuosity index (TI) was calculated from the skull base until the carotid bifurcation and aortic arch, and was defined as the centerline’s true length divided by the straight line distance. Intraclass correlation coefficients (ICC) with 95% confidence intervals were calculated to quantify inter- and intra-observer variability within one software package, and differences in measured TI between packages.
Results
Inter-observer agreement was nearly perfect for 3mensio, excellent for Vital Images and OsiriX, and substantial for TeraRecon, with ICC 0.99 (0.96–1.0), 0.90 (0.69–0.97), 0.84 (0.53–0.95), and 0.72 (0.28–0.91), respectively. Intra-observer agreement ranged from ICC 1.0 for 3mensio to 0.91 for TeraRecon. Agreements in TI ranged from ICC 0.99 (0.98–1.0) for 3mensio vs. OsiriX, to 0.95 (0.82–0.98) for 3mensio vs. TeraRecon. Median time needed to complete one round of measurements was highest for OsiriX (
p
 = 0.013).
Conclusions
Carotid artery tortuosity measurements are reproducible and comparable between current commercially available software packages, with high intra-observer agreement. Although the reproducibility differed per software packages, all packages scored an acceptable inter-observer agreement.