Division of Imaging Sciences and Biomedical Engineering, King's College London, UK.
Ultrasound Med Biol. 2013 Jun;39(6):993-1005. doi: 10.1016/j.ultrasmedbio.2012.12.018. Epub 2013 Mar 1.
The use of ultrasound imaging for guidance of cardiac interventional procedures is limited by the small field of view of the ultrasound volume. A larger view can be created by image-based registration of several partially overlapping volumes, but automatic registration is likely to fail unless the registration is initialized close to the volumes' correct alignment. In this article, we use X-ray images to track a transesophageal ultrasound probe and thereby provide initial position information for the registration of the ultrasound volumes. The tracking is possible using multiple X-rays or just a single X-ray for each probe position. We test the method in a phantom experiment and find that with at least 50% overlap, 88% of volume pairs are correctly registered when tracked using three X-rays and 86% when using single X-rays. Excluding failed registrations with errors greater than 10 mm, the average registration accuracy is 2.92 mm between ultrasound volumes and 4.75 mm for locating an ultrasound volume in X-ray space. We conclude that the accuracy and robustness of the registrations are sufficient to provide useful images for interventional guidance.
超声成像在心脏介入手术中的应用受到超声体视野较小的限制。通过对几个部分重叠的体进行基于图像的配准，可以创建更大的视野，但如果配准没有初始接近正确的对准，自动配准可能会失败。在本文中，我们使用 X 射线图像来跟踪经食管超声探头，从而为超声体的配准提供初始位置信息。可以使用多个 X 射线或每个探头位置仅使用一个 X 射线进行跟踪。我们在一个体模实验中测试了该方法，发现当使用三个 X 射线进行跟踪时，88%的体对可以正确配准，而当使用单个 X 射线时，86%的体对可以正确配准。排除误差大于 10 毫米的失败配准，超声体之间的平均配准精度为 2.92 毫米，在 X 射线空间中定位超声体的平均精度为 4.75 毫米。我们得出结论，配准的准确性和鲁棒性足以提供用于介入指导的有用图像。
