 Original Contribution AN EX VIVO EVALUATION OF TOMOGRAPHIC 3-D ULTRASOUND, B-MODE ULTRASOUND, CT AND MR IMAGING TO MEASURE ARTERY DIAMETER, LENGTH AND WALL VOLUME TAGGEDPSTEVEN ROGERS,* ,y JOAO CARREIRA, y RUTH THOMPSON, y ANA MORAIS, y CHRISTOPHER MILLER,* ,y,z WOLFGANG WEIN, x JONATHAN GHOSH, { and CHARLES MCCOLLUM*TAGGEDEND * Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Oxford Road, Manchester, M13 9PL, UK; y Department of Cardiology, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Southmoor Road, Wythenshawe, Manchester, M13 9PL, UK.; z Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology & Regenerative Medicine, School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Oxford Road, Manchester, M13 9PL, UK; x ImFusion GmbH, Munich, Germany; and { Department of Vascular and Endovascular Surgery, Wythenshawe Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom (Received 7 January 2019; revised 24 June 2019; in final from 1 July 2019) Abstract—Precise measurement of luminal diameter in arteries is important when planning interventional vas- cular procedures in patients. Measuring wall volume may be important in detecting early artery disease and in the assessment of treatments to prevent atherosclerosis. An ex vivo phantom using porcine arteries was used to evaluate the accuracy with which (i) B-mode ultrasound, (ii) 3-D tomographic ultrasound (tUS), (iii) computed tomography (CT) and (iv) magnetic resonance imaging (MRI) measured length, diameters and volume. The mean error in inner-to-inner diameter measurements by B mode, tUS, CT and MRI were 0.08 § 0.26, 0.73 § 0.96 mm, 0.09 § 0.55 and 0.60 § 1.01 mm, respectively. The mean error in outer-to-outer diameter measure- ments by B mode, tUS, CT and MRI were 1.33 § 0.61, 1.03 § 0.35, 0.02 § 1.00 and 0.47 § 1.32 mm, respec- tively. The mean error in volume measurements by B mode, tUS, CT and MRI were 0.54 § 0.62, 0.06 § 0.09, 0.01 § 0.18 and 0.20 § 0.32 cm 3 , respectively. Errors in length and diameters remain within clinically accept- able thresholds where MRI was the least accurate. tUS was the most accurate method of volume measurement. (E-mail: steven.rogers@ivs-online.co.uk) © 2019 World Federation for Ultrasound in Medicine & Biology. All rights reserved. Key Words: Measurement of arteries, Tomographic 3-D ultrasound, Accuracy. INTRODUCTION Cardiovascular disease (CVD) costs the European econ- omy €210 billion/y with stroke alone costing €45 billion (Wilkins et al. 2017). Atherosclerosis is the predominant cause, initiated from early middle age even though symp- toms develop in later life (Fernandez-Friera et al. 2015). The ability to detect and accurately measure early sub- clinical atherosclerosis, while asymptomatic long before it causes symptomatic disease is vital for prevention and research on treatments designed to prevent or slow the pro- gression of atherosclerosis (Ainsworth et al. 2005). The early detection of atherosclerosis offers the opportunity to reduce risk through smoking cessation, modifying diet, taking exercise and weight loss. For the pharmaceutical industry, the accurate measurement of intimal-medial thickness or pre-atherosclerotic disease allows the evalua- tion of new medications to prevent or slow the progression of atherosclerosis. Carotid intimal-medial thickness (CIMT) is known to be associated with CVD risk, but changes over time are small with wide measurement errors using existing techni- ques (Lorenz et al. 2018). Because CIMT is measured in millimetres, there will be substantial measurement errors based on where the scientist or radiologist places the cur- sor to measure thickness. If the volume of the length of artery of known diameter could be measured, the error associated with measurement would be minimised. Address correspondence to: Steven K. Rogers, Vascular Studies Unit, Wythenshawe Hospital, Manchester University NHS Foundation Trust, Southmoor Road, Manchester, M23 9LT, United Kingdom. E-mail: steven.rogers@ivs-online.co.uk 2819 Ultrasound in Med. & Biol., Vol. 45, No. 10, pp. 28192829, 2019 Copyright © 2019 World Federation for Ultrasound in Medicine & Biology. All rights reserved. Printed in the USA. All rights reserved. 0301-5629/$ - see front matter https://doi.org/10.1016/j.ultrasmedbio.2019.07.002