基于血管内超声图像时空相关性的血流斑点去噪方法

血管内超声成像的优越成像方式使得它越来越广泛地被应用到冠心病的诊断和介入治疗中。但随着超声频率的提高，血流分子回波信号（即血流斑点噪声）也显著增强，这会降低管腔和管壁的对比度，加大医生辨别、测量管腔和斑块几何参数及物理参数的难度。我们提出了一种新颖的去噪方法，它利用血管内超声图像在时间、空间上的相关信息，即组织在时间、空间上的变化比血流小这一事实。实验结果表明该方法能显著地去除斑点噪声，增强管腔和管壁的对比度，更好地帮助医生区别血管壁和周围组织。

A Blood Speckle Reduction Method Based on Temporal-Spatial Relativity of Intravascular Ultrasound

The superior imaging manner of intravascular ultrasound becomes more and more widely used in the diagnosis of coronary heart disease and intervention therapy. However, as the frequency of ultrasound increases, strong speckled echo signal from blood may significantly decrease the contrast of lumen and arterial wall structure, which may make it difficult for doctor to dlferentlate and measure geometrical parameters and physical parameters of lumen and plaque. In this paper a novel noise reduction method is introduced, which utilizes the temporal and spatial information of IUVS, that is blood echo speckles have higher temporal and spatial variation than the arterial wall. When signals transferred into the frequency field, tissue and blood present different frequency spectrum, then a radio of high frequency energy and low frequency energy is introduced to determine speckles or tissue. Result showed that the method can remarkably remove the speckle noise, increase the contrast and help doctor differentiate the arterial wall from the around tissues.