Demura Yutaka, Amano Masashi, Yanagi Yoshiki, Mizumoto Ayaka, Jo Yoshito, Izumi Chisato
Department of Clinical laboratory, National Cerebral and Cardiovascular Center, 6-1 Kishibe-shimmachi, Suita 564-8565, Japan.
Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, 6-1 Kishibe-shimmachi, Osaka 564-8565, Suita, Japan.
Eur Heart J Case Rep. 2022 Oct 14;6(10):ytac411. doi: 10.1093/ehjcr/ytac411. eCollection 2022 Oct.
Superb microvascular imaging (SMI) is a new imaging technique that can reveal low-velocity blood flow without use of a contrast agent. SMI is based on an original algorithm and effectively removes tissue motion artifacts (clutter motion) from the background, thereby preserving visibility of low-velocity blood flow. SMI is expected to be useful for the evaluation of heart diseases, as well as blood vessels.
Here, we report three cases in which a mobile structure in the heart or a blood vessel was detected easily by strong enhancement on SMI. In the heart, the entire mass was strongly enhanced by colour-SMI and had the appearance of 'a fire ball'. In the abdominal aorta and carotid artery, SMI captured a strongly enhanced echo image of a mass and revealed hyperechoic mobile plaque. It was hard to detect with the conventional echocardiography.
It is important to detect mobile intravascular and intracardiac structures as they are risk factors of thrombosis. Echo images are often strongly affected by the skill of the examiner, the patient's body habitus, and the presence of intestinal gas; thus, it is often difficult to detect a small mass with conventional echocardiography. With the use of SMI, even small mobile structures can be displayed at high intensity in comparison with the surrounding blood flow. Therefore, the non-invasive SMI was useful for the detection of mobile intravascular and intracardiac structures. Our findings of the current report may lead to new developments in SMI for imaging in the cardiac region.
超微血管成像（SMI）是一种新的成像技术，无需使用造影剂就能显示低速血流。SMI基于一种原始算法，可有效去除背景中的组织运动伪像（杂波运动），从而保留低速血流的可视性。预计SMI对心脏病以及血管的评估会有帮助。
在此，我们报告三例通过SMI上的强烈增强很容易检测到心脏或血管中移动结构的病例。在心脏中，整个肿块在彩色SMI上强烈增强，呈现出“火球”的外观。在腹主动脉和颈动脉中，SMI捕捉到了肿块的强烈增强回声图像，并显示出高回声移动斑块。用传统超声心动图很难检测到。
检测血管内和心内移动结构很重要，因为它们是血栓形成的危险因素。超声图像常受检查者技术、患者体型和肠道气体的影响；因此，用传统超声心动图检测小肿块往往很困难。使用SMI时，与周围血流相比，即使是小的移动结构也能以高强度显示。因此，无创性SMI对检测血管内和心内移动结构很有用。我们当前报告的研究结果可能会推动SMI在心脏区域成像方面的新发展。
