Reproducibility of Transcranial Doppler ultrasound in the middle cerebral artery

Kaczynski, J., Home, R., Shields, K., Walters, M. , Whiteley, W., Wardlaw, J. and Newby, D. E. (2018) Reproducibility of Transcranial Doppler ultrasound in the middle cerebral artery. Cardiovascular Ultrasound, 16(1), 15. (doi: 10.1186/s12947-018-0133-z) (PMID:30200977) (PMCID:PMC6131943)

Abstract

Transcranial Doppler ultrasound remains the only imaging modality that is capable of real-time measurements of blood flow velocity and microembolic signals in the cerebral circulation. We here assessed the repeatability and reproducibility of transcranial Doppler ultrasound in healthy volunteers and patients with symptomatic carotid artery stenosis.Between March and August 2017, we recruited 20 healthy volunteers and 20 patients with symptomatic carotid artery stenosis. In a quiet temperature-controlled room, two 1-h transcranial Doppler measurements of blood flow velocities and microembolic signals were performed sequentially on the same day (within-day repeatability) and a third 7-14 days later (between-day reproducibility). Levels of agreement were assessed by interclass correlation co-efficient.In healthy volunteers (31±9 years, 11 male), within-day repeatability of Doppler measurements were 0.880 (95% CI 0.726-0.950) for peak velocity, 0.867 (95% CI 0.700-0.945) for mean velocity, and 0.887 (95% CI 0.741-0.953) for end-diastolic velocity. Between-day reproducibility was similar but lower: 0.777 (95% CI 0.526-0.905), 0.795 (95% CI 0.558-0.913), and 0.674 (95% CI 0.349-0.856) respectively. In patients (72±11 years, 11 male), within-day repeatability of Doppler measurements were higher: 0.926 (95% CI 0.826-0.970) for peak velocity, 0.922 (95% CI 0.817-0.968) for mean velocity, and 0.868 (95% CI 0.701-0.945) for end-diastolic velocity. Similarly, between-day reproducibility revealed lower values: 0.800 (95% CI 0.567-0.915), 0.786 (95% CI 0.542-0.909), and 0.778 (95% CI 0.527-0.905) respectively. In both cohorts, the intra-observer Bland Altman analysis demonstrated acceptable mean measurement differences and limits of agreement between series of middle cerebral artery velocity measurements with very few outliers. In patients, the carotid stenoses were 30-40% (n = 9), 40-50% (n = 6), 50-70% (n = 3) and > 70% (n = 2). No spontaneous embolisation was detected in either of the groups.Transcranial Doppler generates reproducible data regarding the middle cerebral artery velocities. However, larger studies are needed to validate its clinical applicability.ClinicalTrial.gov (ID NCT 03050567), retrospectively registered on 15/05/2017.

• Item Type: Articles
• Keywords: This study was funded by the Princess Margaret Research Development Fellowship.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Walters, Professor Matthew
• Authors: Kaczynski, J., Home, R., Shields, K., Walters, M., Whiteley, W., Wardlaw, J., and Newby, D. E.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: Cardiovascular Ultrasound
• Publisher: BMC
• ISSN: 1476-7120
• ISSN (Online): 1476-7120
• Copyright Holders: Copyright © 2018 The Authors
• First Published: First published in Cardiovascular Ultrasound 15(1):15
• Publisher Policy: Reproduced under a Creative Commons License