Mancini G B John, Yeoh Eunice, Abbott David, Chan Sammy
Cardiac Imaging Research Laboratory, Jack Bell Research Centre, Atherosclerosis Reversal Clinic, St Paul's Hospital, University of British Columbia, Vancouver.
Can J Cardiol. 2002 Mar;18(3):259-62.
Endothelial dysfunction is an early finding in diverse vascular diseases and can be measured noninvasively using brachial ultrasound. There is great interest in the potential use of this parameter for assessing interventions or cardiovascular prognosis. Automated image analysis of the ultrasound images would facilitate implementation of such measurements in high throughput clinics and/or large clinical trials.
To compare a new method designed to assess brachial artery diameter and percentage diameter changes through automated, beat-by-beat image processing (Brachial Tools, Medical Imaging Applications, USA), with a nonautomated method (Prosound System, Jet Propulsion Laboratory, USA).
Brachial ultrasound tapes from 12 patients undergoing endothelial function assessment using forearm cuff-occlusion, measurement of flow-mediated dilation and responses to nitroglycerin were analyzed by both methods.
The correlation between the two systems was excellent for both the measurement of absolute diameters (r=0.995, P<0.001) and percentage diameter changes (r=0.973, P<0.001). The automated method demonstrated no bias compared with the frame-by-frame method and excellent precision (0.07 mm and 1.62 percentage diameter change).
The automated method provides valid data while substantially diminishing analysis time.
内皮功能障碍是多种血管疾病的早期表现，可通过肱动脉超声进行无创测量。人们对该参数在评估干预措施或心血管预后方面的潜在应用非常感兴趣。超声图像的自动分析将有助于在高通量诊所和/或大型临床试验中实施此类测量。
比较一种通过自动逐搏图像处理来评估肱动脉直径和直径变化百分比的新方法（肱动脉工具，美国医学影像应用公司）与一种非自动方法（美国喷气推进实验室的Prosound系统）。
两种方法均分析了12例接受内皮功能评估的患者的肱动脉超声录像，这些患者采用前臂袖带阻断法、测量血流介导的血管舒张以及对硝酸甘油的反应。
两种系统在绝对直径测量（r = 0.995，P < 0.001）和直径变化百分比测量（r = 0.973，P < 0.001）方面的相关性都非常好。与逐帧分析方法相比，自动分析方法无偏差且精度极高（绝对直径测量精度为0.07 mm，直径变化百分比测量精度为1.62）。
自动分析方法能提供有效数据，同时大幅缩短分析时间。
