Feature Of The Week 12/06/2015: Heartbeat Optical Coherence Tomography
Intravascular optical coherence tomography (IV-OCT) has gained widespread use over the past few years, offering highly detailed images of the coronary artery pathologies and interventions. In contrast to the cross-sectional view, longitudinal sections and three-dimensional (3D) renderings are affected by cardiac motion artifacts and undersampling, complicating interpretation and measurements. We developed Heartbeat OCT, a new OCT method that overcomes these issues.
This study aims to demonstrate in vivo Heartbeat OCT in a preclinical setting, imaging eliminating cardiac motion artifacts, undersampling and non-uniform rotational distortion, to generate high-quality OCT volumes. Using a micro motor actuated catheter and a MHz sweep rate laser, we created an OCT system that records a densely sampled data set within one cardiac cycle at a pullback speed of 100 mm/s. In vitro imaging experiments were carried out with a human cadaver artery; in vivo imaging experiments were conducted in a healthy swine. The Heartbeat OCT pullback acquisition was triggered by the ECG signal. We compare the performance of Heartbeat OCT and a commercial IV-OCT system.
Heartbeat OCT achieves imaging speeds of 5600 frames per second (fps) in vitro and 4000 fps in vivo, resulting in frame spacing of 18 µm and 25 µm, respectively. The acquired OCT volume is free of NURD, undersampling and cardiac motion artifacts. It shows a smooth lumen of the artery, with clearly identifiable structures such as side branches, microvessels and dissection flaps that are washed out in the coarsely sampled commercial IV-OCT images.
Heartbeat OCT generates comprehensively sampled, motion-free OCT volumes by performing imaging at extremely high speed, resulting in accurate 3D renderings that show the vessel wall in full detail.
For more information see recent Article. Courtesy Tianshi Wang from Erasmus University.