de Korte C L, Cespedes E I, van der Steen A F, Pasterkamp G, Bom N
Exp. Echo Ee 23.02, Erasmus University, PO Box 1738, 3000 DR Rotterdam, The Netherlands.
Eur J Ultrasound. 1998 Aug;7(3):219-24. doi: 10.1016/s0929-8266(98)00043-3.
Intravascular elastography is concerned with methods for measuring the local elastic properties using intravascular ultrasound (IVUS). The elastic properties of the vessel wall and atheroma can be measured through the strain. Knowledge of these mechanical properties is useful for guiding interventional procedures (balloon dilatation, ablation) and detection of plaque vulnerability.
Elastograms and palpograms (images of strain) were constructed using the relative local displacements between IVUS images acquired at two levels of intravascular pressure with a 30-MHz echo catheter. These displacements were estimated from the time shift between gated radio-frequency echo signals using cross-correlation algorithms with interpolation around the peak.
Experiments on gel-based phantoms mimicking atherosclerotic vessels demonstrated the capability of elastography to identify soft and hard plaques independently of the echogenicity contrast. In vitro experiments on human arteries have demonstrated the potential of intravascular elastography to identify different plaque types based on the mechanical properties. These plaques could not be identified using the IVUS image alone. Regions with elevated mechanical stress could also be detected. These stress concentrations are related to plaque fracture.
Intravascular elastography provides information that is frequently unavailable or inconclusive from the IVUS image and therefore may assist in the diagnosis and treatment of atherosclerotic disease.
血管内弹性成像关注的是使用血管内超声（IVUS）测量局部弹性特性的方法。血管壁和动脉粥样硬化斑块的弹性特性可通过应变来测量。了解这些力学特性有助于指导介入手术（球囊扩张、消融）以及检测斑块易损性。
使用30兆赫回声导管在两个血管内压力水平采集的IVUS图像之间的相对局部位移构建弹性图和触诊图（应变图像）。这些位移通过使用互相关算法并在峰值周围进行插值，从门控射频回波信号之间的时间偏移来估计。
在模拟动脉粥样硬化血管的基于凝胶的模型上进行的实验表明，弹性成像能够独立于回声对比识别软斑块和硬斑块。在人体动脉上进行的体外实验表明，血管内弹性成像有潜力根据力学特性识别不同类型的斑块。仅使用IVUS图像无法识别这些斑块。还能检测到机械应力升高的区域。这些应力集中与斑块破裂有关。
血管内弹性成像提供了IVUS图像中常常无法获得或不确定的信息，因此可能有助于动脉粥样硬化疾病的诊断和治疗。
