Ex vivo catheter-based imaging of coronary atherosclerosis using multimodality OCT and NIRAF excited at 633 nm.
Hao Wang, Joseph A Gardecki, Giovanni J Ughi, Paulino Vacas Jacques, Ehsan Hamidi, Guillermo J Tearney
Author Information
Hao Wang: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA ; Department of Biomedical Engineering, Boston University, Boston, Massachusetts, 02215 USA.
Joseph A Gardecki: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA.
Giovanni J Ughi: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA.
Paulino Vacas Jacques: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA.
Ehsan Hamidi: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA.
Guillermo J Tearney: Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA ; Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114 USA ; Harvard-MIT Health Sciences and Technology, Cambridge, Massachusetts, USA.
While optical coherence tomography (OCT) has been shown to be capable of imaging coronary plaque microstructure, additional chemical/molecular information may be needed in order to determine which lesions are at risk of causing an acute coronary event. In this study, we used a recently developed imaging system and double-clad fiber (DCF) catheter capable of simultaneously acquiring both OCT and red excited near-infrared autofluorescence (NIRAF) images (excitation: 633 nm, emission: 680nm to 900nm). We found that NIRAF is elevated in lesions that contain necrotic core - a feature that is critical for vulnerable plaque diagnosis and that is not readily discriminated by OCT alone. We first utilized a DCF ball lens probe and a bench top setup to acquire en face NIRAF images of aortic plaques ex vivo (n = 20). In addition, we used the OCT-NIRAF system and fully assembled catheters to acquire multimodality images from human coronary arteries (n = 15) prosected from human cadaver hearts (n = 5). Comparison of these images with corresponding histology demonstrated that necrotic core plaques exhibited significantly higher NIRAF intensity than other plaque types. These results suggest that multimodality intracoronary OCT-NIRAF imaging technology may be used in the future to provide improved characterization of coronary artery disease in human patients.
