Abstract
Currently, colour-coded duplex sonography (2D-CDS) is clinical standard for detection and grading of ICAS (1, 2) as a relevant risk factor for ischaemic stroke (3, 4). Unlike angiographic imaging modalities, 2D-CDS assesses ICAS by its haemodynamic effects rather than luminal changes1. Therefore, aim of this study was to evaluate freehand 3D ultrasound (3DUS) for direct visualisation and quantification of ICAS. 37 patients with 43 ICAS were examined with 2D-CDS as reference standard and with freehand B-mode respectively power-mode 3DUS. For 3DUS Curefab CS (Curefab Technologies GmbH, Munich, Germany) was used. While 3DUS scanning was done by one examiner, ICAS were manually reconstructed within the virtual 3D-volume and graded by 2 physicians. Stenotic value of 3D reconstructed ICAS was assessed by calculating distal diameter and distal cross-sectional area (CSA) reduction percentage. There was a trend but no significant difference in successful 3D reconstruction of ICAS between B-mode and power mode (examiner 1 [Ex1] 81% versus 93%, examiner 2 [Ex2] 84% versus 88%). Interrater reliability (IR) was best for power-mode 3DUS and assessment of stenotic value as distal CSA reduction percentage (intraclass correlation coefficient [ICC] 0.90) followed by power-mode 3DUS and distal diameter reduction (ICC 0.81). IR was poor for B-mode 3DUS (ICC, distal CSA reduction 0.36; distal diameter reduction 0.51). In comparison to 2D-CDS intermethod reliability was clearly better for power-mode 3DUS (ICC, distal diameter reduction: Ex1 0.85, Ex2 0.78; ICC, distal CSA reduction: Ex1 0.63, Ex2 0.57) than for B-mode 3DUS (ICC, distal diameter reduction: Ex1 0.40, Ex2 0.52; ICC, distal CSA reduction: Ex1 0.15, Ex2 0.51). For power-mode 3DUS (distal diameter reduction) positive predictive value for differentiation between moderate and high-grade ICAS was 0.81 (Ex1) and 0.76 (Ex2) while negative predictive value was 0.92 (Ex1) and 0.91 (Ex2). Power-mode 3DUS is superior to B-mode 3DUS for imaging and quantification of ICAS. It might ideally complement 2D-CDS as initial vascular diagnostic in stroke patients and could be a simple alternative for more invasive and time-consuming imaging modalities like computed tomography angiography or contrast-enhanced magnetic resonance angiography.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
