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Silva VB, Andrade De Jesus D, Klein S, van Walsum T, Cardoso J, Brea LS, Vaz PG. Signal-carrying speckle in optical coherence tomography: a methodological review on biomedical applications. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:030901. [PMID: 35289154 PMCID: PMC8919025 DOI: 10.1117/1.jbo.27.3.030901] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
SIGNIFICANCE Speckle has historically been considered a source of noise in coherent light imaging. However, a number of works in optical coherence tomography (OCT) imaging have shown that speckle patterns may contain relevant information regarding subresolution and structural properties of the tissues from which it is originated. AIM The objective of this work is to provide a comprehensive overview of the methods developed for retrieving speckle information in biomedical OCT applications. APPROACH PubMed and Scopus databases were used to perform a systematic review on studies published until December 9, 2021. From 146 screened studies, 40 were eligible for this review. RESULTS The studies were clustered according to the nature of their analysis, namely static or dynamic, and all features were described and analyzed. The results show that features retrieved from speckle can be used successfully in different applications, such as classification and segmentation. However, the results also show that speckle analysis is highly application-dependant, and the best approach varies between applications. CONCLUSIONS Several of the reviewed analyses were only performed in a theoretical context or using phantoms, showing that signal-carrying speckle analysis in OCT imaging is still in its early stage, and further work is needed to validate its applicability and reproducibility in a clinical context.
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Affiliation(s)
- Vania B. Silva
- University of Coimbra, Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (LIBPhys-UC), Department of Physics, Coimbra, Portugal
- University Medical Center Rotterdam, Department of Radiology and Nuclear Medicine, Erasmus MC, Biomedical Imaging Group Rotterdam, Rotterdam, The Netherlands
| | - Danilo Andrade De Jesus
- University Medical Center Rotterdam, Department of Radiology and Nuclear Medicine, Erasmus MC, Biomedical Imaging Group Rotterdam, Rotterdam, The Netherlands
| | - Stefan Klein
- University Medical Center Rotterdam, Department of Radiology and Nuclear Medicine, Erasmus MC, Biomedical Imaging Group Rotterdam, Rotterdam, The Netherlands
| | - Theo van Walsum
- University Medical Center Rotterdam, Department of Radiology and Nuclear Medicine, Erasmus MC, Biomedical Imaging Group Rotterdam, Rotterdam, The Netherlands
| | - João Cardoso
- University of Coimbra, Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (LIBPhys-UC), Department of Physics, Coimbra, Portugal
| | - Luisa Sánchez Brea
- University Medical Center Rotterdam, Department of Radiology and Nuclear Medicine, Erasmus MC, Biomedical Imaging Group Rotterdam, Rotterdam, The Netherlands
| | - Pedro G. Vaz
- University of Coimbra, Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (LIBPhys-UC), Department of Physics, Coimbra, Portugal
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Cardinell JL, Ramjist JM, Chen C, Shi W, Nguyen NQ, Yeretsian T, Choi M, Chen D, Clark DS, Curtis A, Kim H, Faughnan ME, Yang VXD. Quantification metrics for telangiectasia using optical coherence tomography. Sci Rep 2022; 12:1805. [PMID: 35110554 PMCID: PMC8810896 DOI: 10.1038/s41598-022-05272-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 02/17/2021] [Indexed: 12/02/2022] Open
Abstract
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder that causes vascular malformations throughout the body. The most prevalent and accessible of these lesions are found throughout the skin and mucosa, and often rupture causing bleeding and anemia. A recent increase in potential HHT treatments have created a demand for quantitative metrics that can objectively measure the efficacy of new and developing treatments. We employ optical coherence tomography (OCT)—a high resolution, non-invasive imaging modality in a novel pipeline to image and quantitatively characterize dermal HHT lesion behavior over time or throughout the course of treatment. This study is aimed at detecting detailed morphological changes of dermal HHT lesions to understand the underlying dynamic processes of the disease. We present refined metrics tailored for HHT, developed from a pilot study using 3 HHT patients and 6 lesions over the course of multiple imaging dates, totalling to 26 lesion images. Preliminary results from these lesions are presented in this paper alongside representative OCT images. This study provides a new objective method to analyse and understand HHT lesions using a minimally invasive, accessible, cost-effective, and efficient imaging modality with quantitative metrics describing morphology and blood flow.
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Affiliation(s)
- Jillian L Cardinell
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.
| | - Joel M Ramjist
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada
| | - Chaoliang Chen
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Weisong Shi
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Nhu Q Nguyen
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada
| | - Tiffany Yeretsian
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Matthew Choi
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - David Chen
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Dewi S Clark
- Toronto HHT Centre, Division of Respirology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
| | - Anne Curtis
- Division of Dermatology, University of Toronto, Toronto, ON, Canada
| | - Helen Kim
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Marie E Faughnan
- Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - Victor X D Yang
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China.,Department of Surgery, Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
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Wan M, Liang S, Li X, Duan Z, Zou J, Chen J, Yuan J, Zhang J. Balanced detection spectral-domain optical coherence tomography with a single line-scan camera. OPTICS EXPRESS 2022; 30:2578-2584. [PMID: 35209394 DOI: 10.1364/oe.446941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
This paper describes a balanced detection spectral-domain optical coherence tomography (BD-SD-OCT) system for suppressing autocorrelation (AC) artifacts and increasing the signal-to-noise ratio (SNR). The system employed three optical fiber couplers to generate two phase-opposed interference spectra that were acquired by a single line-scan camera simultaneously. When compared with conventional unbalanced detection SD-OCT systems, the developed BD-SD-OCT system improved the SNR by 5.4-6 dB and suppressed the AC term by 5-10 dB. The imaging quality of the BD-SD-OCT system was evaluated by in vivo imaging of human nail folds and retinas.
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Niemczyk M, Iskander DR. Statistical analysis of corneal OCT speckle: a non-parametric approach. BIOMEDICAL OPTICS EXPRESS 2021; 12:6407-6421. [PMID: 34745745 PMCID: PMC8547992 DOI: 10.1364/boe.437937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
In biomedical optics, it is often of interest to statistically model the amplitude of the speckle using some distributional approximations with their parameters acting as biomarkers. In this paper, a paradigm shift is being advocated in which non-parametric approaches are used. Specifically, a range of distances, evaluated in different domains, between an empirical non-parametric distribution of the normalized speckle amplitude sample and the benchmark Rayleigh distribution, is considered. Using OCT images from phantoms, two ex-vivo experiments with porcine corneas and an in-vivo experiment with human corneas, an evidence is provided that the non-parametric approach, despite its simplicity, could lead to equivalent or better results than the parametric approaches with distributional approximations. Concluding, in practice, the non-parametric approach should be considered as the first choice to speckle modeling before a particular distributional approximation is utilized.
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Miyoshi Y, Kawahara T, Yao M, Uemura H. Clinical outcome of surgical management for symptomatic metastatic spinal cord compression from prostate cancer. BMC Urol 2020; 20:143. [PMID: 32891133 PMCID: PMC7487855 DOI: 10.1186/s12894-020-00713-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 08/31/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Metastatic spinal cord compression (MSCC) from prostate cancer (PC) influences not only patients' prognosis but also their quality of life. However, little is known about the clinical outcome of surgery for MSCC from PC. We evaluated both the oncological and functional outcomes of decompression and reconstruction surgery for patients with symptomatic MSCC from PC. METHODS We assessed 19 patients who underwent decompression and reconstruction surgery for symptomatic MSCC from PC. Of these 19 patients, 8 had metastatic hormone-naïve PC (mHNPC) and 11 had metastatic castration-resistant PC (mCRPC). RESULTS The median age of the patients with mHNPC and mCRPC was 72 and 65 years, respectively. The median prostate-specific antigen level at the time of diagnosis of MSCC in patients with mHNPC and mCRPC was 910 and 67 ng/mL, respectively. Although two of eight patients (25.0%) with mHNPC were ambulatory preoperatively, six patients (75.0%) were ambulatory postoperatively. Among 11 patients with mCRPC, only 3 (27.3%) were ambulatory preoperatively, while 6 (54.5%) were ambulatory postoperatively. The median postoperative overall survival among patients with mHNPC and mCRPC were not reached and 8 months, respectively. CONCLUSIONS Decompression and reconstruction surgery for symptomatic MSCC from PC might contribute to a favorable functional outcome among men with mHNPC and mCRPC. However, its role in improving the oncological outcome remains unclear. The treatment strategy should be chosen by shared decision-making among patients, urologists, radiation oncologists, and orthopedic surgeons.
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Affiliation(s)
- Yasuhide Miyoshi
- Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa, 2320024, Japan.
| | - Takashi Kawahara
- Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa, 2320024, Japan
| | - Masahiro Yao
- Department of Urology, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 2360004, Japan
| | - Hiroji Uemura
- Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa, 2320024, Japan
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Chen C, Shi W, Yang VXD. Real-time en-face Gabor optical coherence tomographic angiography on human skin using CUDA GPU. BIOMEDICAL OPTICS EXPRESS 2020; 11:2794-2805. [PMID: 32499961 PMCID: PMC7249826 DOI: 10.1364/boe.392499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 05/18/2023]
Abstract
We recently proposed an optical coherence tomographic angiography (OCTA) algorithm, Gabor optical coherence tomographic angiography (GOCTA), which can extract microvascular signals from a spectral domain directly with lower computational complexity compared to other algorithms. In this manuscript, we combine a programmable swept source, an OCT complex signal detecting unit, and graphics process units (GPU) to achieve a real-time en-face GOCTA system for human skin microvascular imaging. The programmable swept source can balance the A-scan rate and the spectral tuning range; the polarization-modulation based complex signal detecting unit can double the imaging depth range, and the GPU can accelerate data processing. C++ and CUDA are used as the programming platform where five parallel threads are created for galvo-driving signal generation, data acquisition, data transfer, data processing, and image display, respectively. Two queues (for the raw data and en-face images, respectively) are used to improve the data exchange efficiency among different devices. In this study, the data acquisition time and data processing time for each 3D complex volume (256×304×608 pixels,) are 405.3 and 173.7 milliseconds respectively. To the best of our knowledge, this is the first time to show en-face microvascular images covering 3×3 mm2 at a refresh rate of 2.5 Hz.
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Affiliation(s)
- Chaoliang Chen
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
| | - Weisong Shi
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
- Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Victor X. D. Yang
- Biophotonics and Bioengineering Lab, Department of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, Ontario, Canada
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Division of Neurosurgery, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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Gao W. Quantitative depth-resolved microcirculation imaging with optical coherence tomography angiography (Part ΙΙ): Microvascular network imaging. Microcirculation 2018; 25:e12376. [DOI: 10.1111/micc.12376] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/11/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Wanrong Gao
- Department of Optical Engineering; Nanjing University of Science and Technology; Nanjing Jiangsu China
- MIIT Key Laboratory of Advanced Solid Laser; Nanjing University of Science and Technology; Nanjing Jiangsu China
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Cheng Y, Guo L, Pan C, Lu T, Hong T, Ding Z, Li P. Statistical analysis of motion contrast in optical coherence tomography angiography. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:116004. [PMID: 26524681 DOI: 10.1117/1.jbo.20.11.116004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 10/02/2015] [Indexed: 05/08/2023]
Abstract
Optical coherence tomography angiography (Angio-OCT), mainly based on the temporal dynamics of OCT scattering signals, has found a range of potential applications in clinical and scientific research. Based on the model of random phasor sums, temporal statistics of the complex-valued OCT signals are mathematically described. Statistical distributions of the amplitude differential and complex differential Angio-OCT signals are derived. The theories are validated through the flow phantom and live animal experiments. Using the model developed, the origin of the motion contrast in Angio-OCT is mathematically explained, and the implications in the improvement of motion contrast are further discussed, including threshold determination and its residual classification error, averaging method, and scanning protocol. The proposed mathematical model of Angio-OCT signals can aid in the optimal design of the system and associated algorithms.
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Affiliation(s)
- Yuxuan Cheng
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
| | - Li Guo
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
| | - Cong Pan
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
| | - Tongtong Lu
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
| | - Tianyu Hong
- Zhejiang University, College of Biomedical Engineering and Instrument Science, Hangzhou, Zhejiang 310027, China
| | - Zhihua Ding
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
| | - Peng Li
- Zhejiang University, College of Optical Science and Engineering, State Key Laboratory of Modern Optical Instrumentation and the Collaborative Innovation Center for Brain Science, Hangzhou, Zhejiang 310027, China
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Lozzi A, Agrawal A, Boretsky A, Welle CG, Hammer DX. Image quality metrics for optical coherence angiography. BIOMEDICAL OPTICS EXPRESS 2015; 6:2435-2447. [PMID: 26203372 PMCID: PMC4505700 DOI: 10.1364/boe.6.002435] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/13/2015] [Accepted: 06/09/2015] [Indexed: 05/20/2023]
Abstract
We characterized image quality in optical coherence angiography (OCA) en face planes of mouse cortical capillary network in terms of signal-to-noise ratio (SNR) and Weber contrast (Wc) through a novel mask-based segmentation method. The method was used to compare two adjacent B-scan processing algorithms, (1) average absolute difference (AAD) and (2) standard deviation (SD), while varying the number of lateral cross-sections acquired (also known as the gate length, N). AAD and SD are identical at N = 2 and exhibited similar image quality for N<10. However, AAD is relatively less susceptible to bulk tissue motion artifact than SD. SNR and Wc were 15% and 35% higher for AAD from N = 25 to 100. In addition data sets were acquired with two objective lenses with different magnifications to quantify the effect of lateral resolution on fine capillary detection. The lower power objective yielded a significant mean broadening of 17% in Full Width Half Maximum (FWHM) diameter. These results may guide study and device designs for OCA capillary and blood flow quantification.
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Affiliation(s)
- Andrea Lozzi
- Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring MD 20993, USA
| | - Anant Agrawal
- Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring MD 20993, USA
| | - Adam Boretsky
- Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring MD 20993, USA
| | - Cristin G. Welle
- Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring MD 20993, USA
| | - Daniel X. Hammer
- Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring MD 20993, USA
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Farooq H, Genis H, Alarcon J, Vuong B, Jivraj J, Yang VXD, Cohen-Adad J, Fehlings MG, Cadotte DW. High-resolution imaging of the central nervous system: how novel imaging methods combined with navigation strategies will advance patient care. PROGRESS IN BRAIN RESEARCH 2015; 218:55-78. [PMID: 25890132 DOI: 10.1016/bs.pbr.2014.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This narrative review captures a subset of recent advances in imaging of the central nervous system. First, we focus on improvements in the spatial and temporal profile afforded by optical coherence tomography, fluorescence-guided surgery, and Coherent Anti-Stokes Raman Scattering Microscopy. Next, we highlight advances in the generation and uses of imaging-based atlases and discuss how this will be applied to specific clinical situations. To conclude, we discuss how these and other imaging tools will be combined with neuronavigation techniques to guide surgeons in the operating room. Collectively, this work aims to highlight emerging biomedical imaging strategies that hold potential to be a valuable tool for both clinicians and researchers in the years to come.
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Affiliation(s)
- Hamza Farooq
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada
| | - Helen Genis
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada
| | - Joseph Alarcon
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada
| | - Barry Vuong
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada
| | - Jamil Jivraj
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada
| | - Victor X D Yang
- Biophotonics and Bioengineering Laboratory, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada; Physical Science-Brain Sciences Research Program, Sunnybrook Research Institute, University of Toronto, Toronto, ON, Canada; Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada; Division of Neurosurgery, Department of Surgery, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Julien Cohen-Adad
- Institute of Biomedical Engineering, Ecole Polytechnique de Montréal, SensoriMotor Rehabilitation Research Team of the Canadian Institute of Health Research, Montreal, QC, Canada
| | - Michael G Fehlings
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, University of Toronto, Toronto, ON, Canada; Toronto Western Hospital, University Health Network, Toronto, ON, Canada
| | - David W Cadotte
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, University of Toronto, Toronto, ON, Canada; Toronto Western Hospital, University Health Network, Toronto, ON, Canada.
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