O'Malley Sean M, Granada Juan F, Carlier Stéphane, Naghavi Morteza, Kakadiaris Ioannis A
Department of Computer Science, University of Houston, Houston, TX 77204, USA.
IEEE Trans Inf Technol Biomed. 2008 May;12(3):299-306. doi: 10.1109/titb.2008.921014.
Intravascularultrasound (IVUS) sequences recorded in vivo are subject to a wide array of motion artifacts as the majority of these studies are performed within the coronary arteries of a beating heart. To eliminate these artifacts, an electrocardiogram (ECG) signal is typically used to gate (collect) those frames recorded at the points in time associated with a particular fraction of the cardiac cycle. However, this technique may be suboptimal for a number of reasons, among which is the difficulty of determining the optimal fraction at which to gate. This value is generally nonobvious. To circumvent this problem, we introduce a frame-gating method for IVUS pullbacks that mimics ECG (i.e., in the sense that it selects only one frame per cardiac cycle), but will automatically choose the fraction of the cycle that renders the most stable gated frame set. Stability here is gauged by measuring interframe similarity. Our method operates exclusively on the imagery data and does not require ECG or any form of image segmentation or other high-level image analysis. To validate our algorithm, we compare its behavior versus true ECG gating.
由于大多数体内记录的血管内超声（IVUS）序列研究是在跳动心脏的冠状动脉内进行的，因此会受到各种各样的运动伪影影响。为了消除这些伪影，通常使用心电图（ECG）信号来选通（采集）那些在与心动周期特定部分相关的时间点记录的帧。然而，由于多种原因，这种技术可能并非最佳选择，其中之一就是难以确定选通的最佳部分。这个值通常并不明显。为了解决这个问题，我们引入了一种用于IVUS回撤的帧选通方法，该方法模仿心电图（即，它在每个心动周期仅选择一帧的意义上），但会自动选择能产生最稳定选通帧集的心动周期部分。这里的稳定性是通过测量帧间相似度来衡量的。我们的方法仅对图像数据进行操作，不需要心电图或任何形式的图像分割或其他高级图像分析。为了验证我们的算法，我们将其行为与真正的心电图选通进行了比较。
