Abstract 14957: Investigation of Myocardial Birefringence using Polarization-Sensitive Optical Coherence Tomography in a Mouse Model of Myocardial Infarction

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Sun-Joo Jang ◽  
Tae Jin Park ◽  
Wang-Yuhl Oh

Introduction: Although several imaging modalities have been utilized to characterize myocardium, the birefringence of myocardium has not been spotlighted. The polarization-sensitive optical coherence tomography (PS-OCT) is a novel imaging method for the characterization of tissue birefringence. Hypothesis: The birefringence of infarcted myocardium would be different from non-infarcted myocardium. We examined the myocardial birefringence in a mouse coronary artery ligation model using PS-OCT. Methods: Male C57B/6 mice (20-30g) underwent thoracotomy and the ligation of left anterior descending artery. At post-myocardial infarction (post-MI) 3 hours or on post-MI day 28, the left anterior wall of the mice was imaged with PS-OCT in vivo and ex vivo. The local phase retardation for tissue birefringence, the local principal axis directional uniformity for tissue orientation, and the degree of polarization uniformity were demonstrated and compared with collagen fiber staining (picrosirius red). For PS-OCT system, wavelength-swept laser with 140 nm bandwidth (center wavelength = 1,280 nm) and 120 kHz A-line rate was used. Results: The endocardial border could be detected by high birefringence of myocardium. There was no difference in the birefringence between systole and diastole. The infarcted anterior wall showed dyskinesia or hypokinesia. The systolic wall thickening was lower in the infarcted wall compared to the normal anterior wall. At post-MI 3 hours, there was no significant change in myocardial birefringence. On day 28, the infarcted myocardium with scar tissue showed low level of local birefringence with irregular tissue orientation compared to the normal myocardium. The 3D reconstructed images were used to differentiate transmural or subendocardial MI. Conclusions: Our study demonstrated that the PS-OCT would be helpful for the evaluation of myocardial function and tissue characterization in myocardial infarction.

2013 ◽  
Vol 14 (5) ◽  
pp. 393-394 ◽  
Author(s):  
Massimo Fineschi ◽  
Vasile Sirbu ◽  
Flavio D’Ascenzi ◽  
Arcangelo Carrera ◽  
Riccardo Barbati ◽  
...  

2021 ◽  
Vol 127 (4) ◽  
Author(s):  
S. Skruszewicz ◽  
S. Fuchs ◽  
J. J. Abel ◽  
J. Nathanael ◽  
J. Reinhard ◽  
...  

AbstractWe present an overview of recent results on optical coherence tomography with the use of extreme ultraviolet and soft X-ray radiation (XCT). XCT is a cross-sectional imaging method that has emerged as a derivative of optical coherence tomography (OCT). In contrast to OCT, which typically uses near-infrared light, XCT utilizes broad bandwidth extreme ultraviolet (XUV) and soft X-ray (SXR) radiation (Fuchs et al in Sci Rep 6:20658, 2016). As in OCT, XCT’s axial resolution only scales with the coherence length of the light source. Thus, an axial resolution down to the nanometer range can be achieved. This is an improvement of up to three orders of magnitude in comparison to OCT. XCT measures the reflected spectrum in a common-path interferometric setup to retrieve the axial structure of nanometer-sized samples. The technique has been demonstrated with broad bandwidth XUV/SXR radiation from synchrotron facilities and recently with compact laboratory-based laser-driven sources. Axial resolutions down to 2.2 nm have been achieved experimentally. XCT has potential applications in three-dimensional imaging of silicon-based semiconductors, lithography masks, and layered structures like XUV mirrors and solar cells.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Yi Sun ◽  
Jianfeng Wang ◽  
Jindou Shi ◽  
Stephen A. Boppart

AbstractPolarization-sensitive optical coherence tomography (PS-OCT) is a high-resolution label-free optical biomedical imaging modality that is sensitive to the microstructural architecture in tissue that gives rise to form birefringence, such as collagen or muscle fibers. To enable polarization sensitivity in an OCT system, however, requires additional hardware and complexity. We developed a deep-learning method to synthesize PS-OCT images by training a generative adversarial network (GAN) on OCT intensity and PS-OCT images. The synthesis accuracy was first evaluated by the structural similarity index (SSIM) between the synthetic and real PS-OCT images. Furthermore, the effectiveness of the computational PS-OCT images was validated by separately training two image classifiers using the real and synthetic PS-OCT images for cancer/normal classification. The similar classification results of the two trained classifiers demonstrate that the predicted PS-OCT images can be potentially used interchangeably in cancer diagnosis applications. In addition, we applied the trained GAN models on OCT images collected from a separate OCT imaging system, and the synthetic PS-OCT images correlate well with the real PS-OCT image collected from the same sample sites using the PS-OCT imaging system. This computational PS-OCT imaging method has the potential to reduce the cost, complexity, and need for hardware-based PS-OCT imaging systems.


2012 ◽  
Vol 13 (3) ◽  
pp. 202.e5-202.e6
Author(s):  
Righab Hamdan ◽  
Ricardo Garcia Gonzalez ◽  
Christophe Caussin ◽  
Said Ghostine

2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Tor Skibsted Clemmensen ◽  
Niels Ramsing Holm ◽  
Hans Eiskjær ◽  
Steen Hvitfeldt Poulsen ◽  
Michael Maeng ◽  
...  

The case illustrates the possible link between coronary spasms, intraluminal thrombus formation, and widespread organized and layered thrombi in HTx patients. Furthermore, the case underlines the clinical value of OCT as a novel method for high-resolution vessel imaging in heart-transplanted (HTx) patients with coronary spasms and suspected coronary artery disease. Coronary spasms and sudden death are frequent complications after HTx. The underlying mechanisms leading to these complications are unknown. The present case displays the clinical course of a 19-year-old HTx patient who was hospitalized due to acute myocardial infarction induced by severe coronary spasms. The patients remained unstable on conservative therapy. Therefore, an optical coherence tomography (OCT) was performed and revealed massive, organized thrombi in the left main coronary artery, the circumflex coronary artery, and the left anterior descending coronary artery. The patient was stabilized after percutaneous coronary intervention. As a mural thrombus often goes undetected by coronary angiography, OCT may prove benefit in HTx patients with myocardial infarction or suspected coronary spasms.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Xiaoyan Li ◽  
Xuejun Jliang ◽  
Tao Wang ◽  
Taol Lin ◽  
Congxin Huang ◽  
...  

Myocardial infarction and the subsequent heart failure remain among the world’s prominent health challenges. Other studies have demonstrated that bio-derived materials improve cardiac function after implantation for angiogenic potential. In this study, we hypothesized that injection of biomaterials into infarcted myocardium can preserve left ventricle (LV) function through its prevention of paradoxical systolic bulging. Infarction was induced in rabbit myocardium by coronary artery ligation. In sham-operated rabbits (n = 5), a suture was tied loosely around the left anterior descending coronary artery without ligating it. 7 dayslater, 100μl α-cyclodextrin (CD) solution and 100μl poly (ethylene glycol)-b-polycaprolactone-(dodecanedioic acid)-polycaprolactone-poly (ethylene glycol)(MPEG-PCL-MPEG) solution (n = 7) was injected simultaneously through Duploject applicator into the infarcted myocardium. Solid hydrogel matrix formed by linear MPEG-PCL-MPEG polymer threading into the cavities of the α-cyclodextrin after mixing. Injection of phosphate buffered saline (PBS) served as controls (n = 7). 28 days after the treatments, histological analysis indicated that injection of hydrogel prevented scar expansion and wall thinning compared with group ( P < 0.05) without more microvessel density in infarcted myocardium ( P = 0.70).By echocardiography, LV ejection fraction was significantly greater in the hydrogel group (56.09 ± 8.42%) than the control group (37.26 ± 6.36%, P = 0.001). The LV end-diastolic and end-systolic diameters were 2.07 ± 0.33 cm and 1.74 ± 0.30cm in the control group, respectively. Smaller LV end-diastolic diameter (1.61 ± 0.26cm, P = 0.005) and smaller end-systolic diameter (1.17 ± 0.23cm, P = 0.001) were found in the hydrogel group. These results suggest that α-CD/MPEG-PCL-MPEG hydrogel injection could serve structural and mechanical support of an injured LV replacing some of the functions of the damaged ECM and thus prevented paradoxical motion serves, which may eventually lead to LV remodeling and dilation prevention. Our study should initiate further experimental and clinical studies exploring potential approaches to the treatment of postinfarction heart failure.


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