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Quiros KAM, Nelson TM, Sattari S, Mariano CA, Ulu A, Dominguez EC, Nordgren TM, Eskandari M. Mouse lung mechanical properties under varying inflation volumes and cycling frequencies. Sci Rep 2022; 12:7094. [PMID: 35501363 PMCID: PMC9059689 DOI: 10.1038/s41598-022-10417-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 03/30/2022] [Indexed: 01/23/2023] Open
Abstract
Respiratory pathologies alter the structure of the lung and impact its mechanics. Mice are widely used in the study of lung pathologies, but there is a lack of fundamental mechanical measurements assessing the interdependent effect of varying inflation volumes and cycling frequency. In this study, the mechanical properties of five male C57BL/6J mice (29–33 weeks of age) lungs were evaluated ex vivo using our custom-designed electromechanical, continuous measure ventilation apparatus. We comprehensively quantify and analyze the effect of loading volumes (0.3, 0.5, 0.7, 0.9 ml) and breathing rates (5, 10, 20 breaths per minute) on pulmonary inflation and deflation mechanical properties. We report means of static compliance between 5.4–16.1 µl/cmH2O, deflation compliance of 5.3–22.2 µl/cmH2O, percent relaxation of 21.7–39.1%, hysteresis of 1.11–7.6 ml•cmH2O, and energy loss of 39–58% for the range of four volumes and three rates tested, along with additional measures. We conclude that inflation volume was found to significantly affect hysteresis, static compliance, starting compliance, top compliance, deflation compliance, and percent relaxation, and cycling rate was found to affect only hysteresis, energy loss, percent relaxation, static compliance and deflation compliance.
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2
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Imaging the pulmonary extracellular matrix. CURRENT OPINION IN PHYSIOLOGY 2021. [DOI: 10.1016/j.cophys.2021.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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3
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Kuo WC, Kao MC, Ting CK, Teng WN. Optical Coherence Tomography Needle Probe in Neuraxial Block Application. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS 2021; 27:1-6. [DOI: 10.1109/jstqe.2020.3042076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Wen-Chuan Kuo
- Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan
| | - Meng-Chun Kao
- Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan
| | - Chien-Kun Ting
- Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
| | - Wei-Nung Teng
- Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
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4
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Sattari S, Mariano CA, Vittalbabu S, Velazquez JV, Postma J, Horst C, Teh E, Nordgren TM, Eskandari M. Introducing a Custom-Designed Volume-Pressure Machine for Novel Measurements of Whole Lung Organ Viscoelasticity and Direct Comparisons Between Positive- and Negative-Pressure Ventilation. Front Bioeng Biotechnol 2020; 8:578762. [PMID: 33195138 PMCID: PMC7643401 DOI: 10.3389/fbioe.2020.578762] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022] Open
Abstract
Asthma, emphysema, COVID-19 and other lung-impacting diseases cause the remodeling of tissue structural properties and can lead to changes in conducting pulmonary volume, viscoelasticity, and air flow distribution. Whole organ experimental inflation tests are commonly used to understand the impact of these modifications on lung mechanics. Here we introduce a novel, automated, custom-designed device for measuring the volume and pressure response of lungs, surpassing the capabilities of traditional machines and built to range size-scales to accommodate both murine and porcine tests. The software-controlled system is capable of constructing standardized continuous volume-pressure curves, while accounting for air compressibility, yielding consistent and reproducible measures while eliminating the need for pulmonary degassing. This device uses volume-control to enable viscoelastic whole lung macromechanical insights from rate dependencies and pressure-time curves. Moreover, the conceptual design of this device facilitates studies relating the phenomenon of diaphragm breathing and artificial ventilation induced by pushing air inside the lungs. System capabilities are demonstrated and validated via a comparative study between ex vivo murine lungs and elastic balloons, using various testing protocols. Volume-pressure curve comparisons with previous pressure-controlled systems yield good agreement, confirming accuracy. This work expands the capabilities of current lung experiments, improving scientific investigations of healthy and diseased pulmonary biomechanics. Ultimately, the methodologies demonstrated in the manufacturing of this system enable future studies centered on investigating viscoelasticity as a potential biomarker and improvements to patient ventilators based on direct assessment and comparisons of positive- and negative-pressure mechanics.
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Affiliation(s)
- Samaneh Sattari
- Department of Mechanical Engineering, University of California, Riverside, Riverside, CA, United States
| | - Crystal A Mariano
- Department of Mechanical Engineering, University of California, Riverside, Riverside, CA, United States
| | - Swathi Vittalbabu
- Department of Mechanical Engineering, University of California, Riverside, Riverside, CA, United States
| | - Jalene V Velazquez
- BREATHE Center at the School of Medicine, University of California, Riverside, Riverside, CA, United States.,Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | | | - Caleb Horst
- CellScale Biomaterials Testing, Waterloo, ON, Canada
| | - Eric Teh
- CellScale Biomaterials Testing, Waterloo, ON, Canada
| | - Tara M Nordgren
- BREATHE Center at the School of Medicine, University of California, Riverside, Riverside, CA, United States.,Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Mona Eskandari
- Department of Mechanical Engineering, University of California, Riverside, Riverside, CA, United States.,BREATHE Center at the School of Medicine, University of California, Riverside, Riverside, CA, United States.,Department of Bioengineering, University of California, Riverside, Riverside, CA, United States
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5
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Criner GJ, Eberhardt R, Fernandez-Bussy S, Gompelmann D, Maldonado F, Patel N, Shah PL, Slebos DJ, Valipour A, Wahidi MM, Weir M, Herth FJ. Interventional Bronchoscopy. Am J Respir Crit Care Med 2020; 202:29-50. [PMID: 32023078 DOI: 10.1164/rccm.201907-1292so] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
For over 150 years, bronchoscopy, especially flexible bronchoscopy, has been a mainstay for airway inspection, the diagnosis of airway lesions, therapeutic aspiration of airway secretions, and transbronchial biopsy to diagnose parenchymal lung disorders. Its utility for the diagnosis of peripheral pulmonary nodules and therapeutic treatments besides aspiration of airway secretions, however, has been limited. Challenges to the wider use of flexible bronchoscopy have included difficulty in navigating to the lung periphery, the avoidance of vasculature structures when performing diagnostic biopsies, and the ability to biopsy a lesion under direct visualization. The last 10-15 years have seen major advances in thoracic imaging, navigational platforms to direct the bronchoscopist to lung lesions, and the ability to visualize lesions during biopsy. Moreover, multiple new techniques have either become recently available or are currently being investigated to treat a broad range of airway and lung parenchymal diseases, such as asthma, emphysema, and chronic bronchitis, or to alleviate recurrent exacerbations. New bronchoscopic therapies are also being investigated to not only diagnose, but possibly treat, malignant peripheral lung nodules. As a result, flexible bronchoscopy is now able to provide a new and expanding armamentarium of diagnostic and therapeutic tools to treat patients with a variety of lung diseases. This State-of-the-Art review succinctly reviews these techniques and provides clinicians an organized approach to their role in the diagnosis and treatment of a range of lung diseases.
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Affiliation(s)
- Gerard J Criner
- Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Ralf Eberhardt
- Pneumology and Critical Care Medicine, Thoraxklinik, University of Heidelberg, Heidelberg, Germany
| | | | - Daniela Gompelmann
- Pneumology and Critical Care Medicine, Thoraxklinik, University of Heidelberg, Heidelberg, Germany
| | - Fabien Maldonado
- Department of Medicine and Department of Thoracic Surgery, Vanderbilt University, Nashville, Tennessee
| | - Neal Patel
- Division of Pulmonary Medicine, Mayo Clinic, Jacksonville, Florida
| | - Pallav L Shah
- Respiratory Medicine at the Royal Brompton Hospital and National Heart & Lung Institute, Imperial College, London, United Kingdom
| | - Dirk-Jan Slebos
- Department of Pulmonary Diseases, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Arschang Valipour
- Department of Respiratory and Critical Care Medicine, Krankenhaus Nord, Vienna, Austria; and
| | - Momen M Wahidi
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina
| | - Mark Weir
- Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Felix J Herth
- Pneumology and Critical Care Medicine, Thoraxklinik, University of Heidelberg, Heidelberg, Germany
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6
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Goorsenberg A, Kalverda KA, Annema J, Bonta P. Advances in Optical Coherence Tomography and Confocal Laser Endomicroscopy in Pulmonary Diseases. Respiration 2019; 99:190-205. [PMID: 31593955 DOI: 10.1159/000503261] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 09/05/2019] [Indexed: 12/13/2022] Open
Abstract
Diagnosing and monitoring pulmonary diseases is highly dependent on imaging, physiological function tests and tissue sampling. Optical coherence tomography (OCT) and confocal laser endomicroscopy (CLE) are novel imaging techniques with near-microscopic resolution that can be easily and safely combined with conventional bronchoscopy. Disease-related pulmonary anatomical compartments can be visualized, real time, using these techniques. In obstructive lung diseases, airway wall layers and related structural remodelling can be identified and quantified. In malignant lung disease, normal and malignant areas of the central airways, lung parenchyma, lymph nodes and pleura can be discriminated. A growing number of interstitial lung diseases (ILDs) have been visualized using OCT or CLE. Several ILD-associated structural changes can be imaged: fibrosis, cellular infiltration, bronchi(ol)ectasis, cysts and microscopic honeycombing. Although not yet implemented in clinical practice, OCT and CLE have the potential to improve detection and monitoring pulmonary diseases and can contribute in unravelling the pathophysiology of disease and mechanism of action of novel treatments. Indeed, assessment of the airway wall layers with OCT might be helpful when evaluating treatments targeting airway remodelling. By visualizing individual malignant cells, CLE has the potential as a real-time lung cancer detection tool. In the future, both techniques could be combined with laser-enhanced fluorescent-labelled tracer detection. This review discusses the value of OCT and CLE in pulmonary medicine by summarizing the current evidence and elaborating on future perspectives.
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Affiliation(s)
- Annika Goorsenberg
- Department of Pulmonology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands,
| | - Kirsten A Kalverda
- Department of Pulmonology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Jouke Annema
- Department of Pulmonology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Peter Bonta
- Department of Pulmonology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
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Abstract
Gabor-domain optical coherence microscopy (GDOCM) is a high-definition imaging technique leveraging principles of low-coherence interferometry, liquid lens technology, high-speed imaging, and precision scanning. GDOCM achieves isotropic 2 μm resolution in 3D, effectively breaking the cellular resolution limit of optical coherence tomography (OCT). In the ten years since its introduction, GDOCM has been used for cellular imaging in 3D in a number of clinical applications, including dermatology, oncology and ophthalmology, as well as to characterize materials in industrial applications. Future developments will enhance the structural imaging capability of GDOCM by adding functional modalities, such as fluorescence and elastography, by estimating thicknesses on the nano-scale, and by incorporating machine learning techniques.
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Price HB, Kimbell JS, Bu R, Oldenburg AL. Geometric Validation of Continuous, Finely Sampled 3-D Reconstructions From aOCT and CT in Upper Airway Models. IEEE TRANSACTIONS ON MEDICAL IMAGING 2019; 38:1005-1015. [PMID: 30334787 PMCID: PMC6476567 DOI: 10.1109/tmi.2018.2876625] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Identification and treatment of obstructive airway disorders (OADs) are greatly aided by imaging of the geometry of the airway lumen. Anatomical optical coherence tomography (aOCT) is a promising high-speed and minimally invasive endoscopic imaging modality for providing micrometer-resolution scans of the upper airway. Resistance to airflow in OADs is directly caused by the reduction in luminal cross-sectional area (CSA). It is hypothesized that aOCT can produce airway CSA measurements as accurate as that from computed tomography (CT). Scans of machine hollowed cylindrical tubes were used to develop methods for segmentation and measurement of airway lumen in CT and aOCT. Simulated scans of virtual cones were used to validate 3-D resampling and reconstruction methods in aOCT. Then, measurements of two segments of a 3-D printed pediatric airway phantom from aOCT and CT independently were compared to ground truth CSA. In continuous unobstructed regions, the mean CSA difference for each phantom segment was 2.2 ± 3.5 and 1.5 ± 5.3 mm2 for aOCT, and -3.4 ± 4.3 and -1.9 ± 1.2 mm2 for CT. Because of the similar magnitude of these differences, these results support the hypotheses and underscore the potential for aOCT as a viable alternative to CT in airway imaging, while offering greater potential to capture respiratory dynamics.
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Affiliation(s)
- Hillel B. Price
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 USA ()
| | - Julia S. Kimbell
- Department of Otolaryngology/Head and Neck Surgery, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7070 USA; Department of Biomedical Engineering, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3216 USA ()
| | - Ruofei Bu
- Department of Biomedical Medical Engineering, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3216 USA ()
| | - Amy L. Oldenburg
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 USA; Biomedical Research Imaging Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7513 USA; Department of Biomedical Medical Engineering, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3216 USA ()
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Monroy GL, Won J, Spillman DR, Dsouza R, Boppart SA. Clinical translation of handheld optical coherence tomography: practical considerations and recent advancements. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-30. [PMID: 29260539 PMCID: PMC5735247 DOI: 10.1117/1.jbo.22.12.121715] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/04/2017] [Indexed: 05/21/2023]
Abstract
Since the inception of optical coherence tomography (OCT), advancements in imaging system design and handheld probes have allowed for numerous advancements in disease diagnostics and characterization of the structural and optical properties of tissue. OCT system developers continue to reduce form factor and cost, while improving imaging performance (speed, resolution, etc.) and flexibility for applicability in a broad range of fields, and nearly every clinical specialty. An extensive array of components to construct customized systems has also become available, with a range of commercial entities that produce high-quality products, from single components to full systems, for clinical and research use. Many advancements in the development of these miniaturized and portable systems can be linked back to a specific challenge in academic research, or a clinical need in medicine or surgery. Handheld OCT systems are discussed and explored for various applications. Handheld systems are discussed in terms of their relative level of portability and form factor, with mention of the supporting technologies and surrounding ecosystem that bolstered their development. Additional insight from our efforts to implement systems in several clinical environments is provided. The trend toward well-designed, efficient, and compact handheld systems paves the way for more widespread adoption of OCT into point-of-care or point-of-procedure applications in both clinical and commercial settings.
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Affiliation(s)
- Guillermo L. Monroy
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Jungeun Won
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Darold R. Spillman
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Roshan Dsouza
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Electrical and Computer Engineering, Urbana, Illinois, United States
- Carle-Illinois College of Medicine, Urbana, Illinois, United States
- Address all correspondence to: Stephen A. Boppart, E-mail:
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Tsai TH, Leggett CL, Trindade AJ, Sethi A, Swager AF, Joshi V, Bergman JJ, Mashimo H, Nishioka NS, Namati E. Optical coherence tomography in gastroenterology: a review and future outlook. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-17. [PMID: 29260538 DOI: 10.1117/1.jbo.22.12.121716] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/05/2017] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT) is an imaging technique optically analogous to ultrasound that can generate depth-resolved images with micrometer-scale resolution. Advances in fiber optics and miniaturized actuation technologies allow OCT imaging of the human body and further expand OCT utilization in applications including but not limited to cardiology and gastroenterology. This review article provides an overview of current OCT development and its clinical utility in the gastrointestinal tract, including disease detection/differentiation and endoscopic therapy guidance, as well as a discussion of its future applications.
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Affiliation(s)
- Tsung-Han Tsai
- NinePoint Medical, Inc., Bedford, Massachusetts, United States
| | - Cadman L Leggett
- Mayo Clinics, Division of Gastroenterology and Hepatology, Rochester, Minnesota, United States
| | - Arvind J Trindade
- North Shore University Hospital and Hofstra Northwell School of Medicine, Division of Gastroenterolo, United States
| | - Amrita Sethi
- Columbia University Medical Center, Department of Gastroenterology, New York City, New York, United States
| | - Anne-Fré Swager
- Spaarne Gasthuis and Free University Medical Center, Amsterdam, The Netherlands
| | - Virendra Joshi
- Ochsner Clinic Foundation, Department of Gastroenterology, New Orleans, Louisiana, United States
| | - Jacques J Bergman
- Academic Medical Center, Department of Gastroenterology and Hepatology, Amsterdam, The Netherlands
| | - Hiroshi Mashimo
- Veterans Affairs Boston Healthcare System and Harvard Medical School, Department of Gastroenterology, United States
| | - Norman S Nishioka
- Massachusetts General Hospital, Gastrointestinal Unit, Boston, Massachusetts, United States
| | - Eman Namati
- NinePoint Medical, Inc., Bedford, Massachusetts, United States
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11
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Li J, Quirk BC, Noble PB, Kirk RW, Sampson DD, McLaughlin RA. Flexible needle with integrated optical coherence tomography probe for imaging during transbronchial tissue aspiration. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-5. [PMID: 29022301 DOI: 10.1117/1.jbo.22.10.106002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
Transbronchial needle aspiration (TBNA) of small lesions or lymph nodes in the lung may result in nondiagnostic tissue samples. We demonstrate the integration of an optical coherence tomography (OCT) probe into a 19-gauge flexible needle for lung tissue aspiration. This probe allows simultaneous visualization and aspiration of the tissue. By eliminating the need for insertion and withdrawal of a separate imaging probe, this integrated design minimizes the risk of dislodging the needle from the lesion prior to aspiration and may facilitate more accurate placement of the needle. Results from in situ imaging in a sheep lung show clear distinction between solid tissue and two typical constituents of nondiagnostic samples (adipose and lung parenchyma). Clinical translation of this OCT-guided aspiration needle holds promise for improving the diagnostic yield of TBNA.
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Affiliation(s)
- Jiawen Li
- University of Adelaide, Adelaide Medical School, Australian Research Council Centre of Excellence fo, Australia
- University of Adelaide, Institute for Photonics and Advanced Sensing, Adelaide, South Australia, Australia
| | - Bryden C Quirk
- University of Adelaide, Adelaide Medical School, Australian Research Council Centre of Excellence fo, Australia
- University of Adelaide, Institute for Photonics and Advanced Sensing, Adelaide, South Australia, Australia
| | - Peter B Noble
- University of Western Australia, School of Human Sciences, Perth, Western Australia, Australia
- University of Western Australia, School of Paediatrics and Child Health, Centre for Neonatal Researc, Australia
| | - Rodney W Kirk
- University of Adelaide, Adelaide Medical School, Australian Research Council Centre of Excellence fo, Australia
- University of Adelaide, Institute for Photonics and Advanced Sensing, Adelaide, South Australia, Australia
| | - David D Sampson
- University of Western Australia, School of Electrical, Electronic and Computer Engineering, Optical+, Australia
- University of Western Australia, Centre for Microscopy, Characterisation and Analysis, Perth, Wester, Australia
| | - Robert A McLaughlin
- University of Adelaide, Adelaide Medical School, Australian Research Council Centre of Excellence fo, Australia
- University of Adelaide, Institute for Photonics and Advanced Sensing, Adelaide, South Australia, Australia
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Abstract
Peripheral pulmonary lesions (PPLs) are generally considered as lesions in the peripheral one-third of the lung although a precise definition and radiographic anatomical landmarks separating central and peripheral lesion does not yet exist. The radiographic detection of such lesions has increased significantly with the adoption of lung cancer screening programs. These lesions are not directly visible by regular flexible bronchoscopes as they are usually distal to the lobar and segmental bronchi. Traditionally, depending on location and clinical stage at presentation, these lesions were typically sampled by computerized tomography (CT) guided needle or surgical biopsy although some centers also used ultrasound and fluoroscopy guided percutaneous needle biopsy. Due to lack of direct visualization, the yield for bronchoscopic guided sampling especially of the small <2 cm pulmonary nodules was very low. Therefore, sampling has been preferentially performed by percutaneous CT guidance, which had high yield of above 90% but it comes at the cost of higher risk complications like pneumothorax with reported rate of 15% to 28%. Directly proceeding to surgical resection is also considered in appropriate candidates with high suspicion of malignancy without any evidence of distant metastasis but the proportion of such cases of lung cancer is low. The manuscript discussed the various bronchoscopic diagnostic modalities for peripheral pulmonary lesions. It is important to note that most of the studies in this field are relatively small, not randomized, suffer from selection bias, have considerable heterogeneity in sampling methodology/instruments and usually have been performed in high volume institutions by dedicated highly experienced proceduralists. The prevalence of malignancy in most of the reported cohorts has also been high which may result in higher diagnostic yields. All these factors need to be kept in mind before generalizing the results to individual centers and practices.
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Affiliation(s)
- Samjot Singh Dhillon
- Division of Pulmonary Medicine and Interventional Pulmonology, Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - Kassem Harris
- Division of Pulmonary and Critical Care Medicine, Section of Interventional Pulmonology, Westchester Medical Center, Valhalla, NY, USA
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13
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Optical coherence tomography and confocal laser endomicroscopy in pulmonary diseases. Curr Opin Pulm Med 2017; 23:275-283. [DOI: 10.1097/mcp.0000000000000375] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kizhakke Puliyakote AS, Vasilescu DM, Newell JD, Wang G, Weibel ER, Hoffman EA. Morphometric differences between central vs. surface acini in A/J mice using high-resolution micro-computed tomography. J Appl Physiol (1985) 2016; 121:115-22. [PMID: 27174924 DOI: 10.1152/japplphysiol.00317.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/06/2016] [Indexed: 11/22/2022] Open
Abstract
Through interior tomography, high-resolution microcomputed tomography (μCT) systems provide the ability to nondestructively assess the pulmonary acinus at micron and submicron resolutions. With the application of systematic uniform random sampling (SURS) principles applied to in situ fixed, intact, ex vivo lungs, we have sought to characterize morphometric differences in central vs. surface acini to better understand how well surface acini reflect global acinar geometry. Lungs from six mice (A/J strain, 15-20 wk of age) were perfusion fixed in situ and imaged using a multiresolution μCT system (Micro XCT 400, Zeiss). With the use of lower-resolution whole lung images, SURS methods were used for identification of central and surface foci for high-resolution imaging. Acinar morphometric metrics included diameters, lengths, and branching angles for each alveolar duct and total path lengths from entrance of the acinus to the terminal alveolar sacs. In addition, acinar volume, alveolar surface area, and surface area/volume ratios were assessed. A generation-based analysis demonstrated that central acini have significantly smaller branch diameters at each generation with no significant increase in branch lengths. In addition to larger-diameter alveolar ducts, surface acini had significantly increased numbers of branches and terminal alveolar sacs. The total path lengths from the acinar entrance to the terminal nodes were found to be higher in the case of surface acini. Volumes and surface areas of surface acini are greater than central acini, but there were no differences in surface/volume ratios. In conclusion, there are significant structural differences between surface and central acini in the A/J mouse.
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Affiliation(s)
- Abhilash S Kizhakke Puliyakote
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | | | - John D Newell
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | - Ge Wang
- Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; Department of Biomedical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | | | - Eric A Hoffman
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa; Department of Medicine, University of Iowa, Iowa City, Iowa;
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15
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Wellikoff AS, Holladay RC, Downie GH, Chaudoir CS, Brandi L, Turbat-Herrera EA. Comparison of in vivo probe-based confocal laser endomicroscopy with histopathology in lung cancer: A move toward optical biopsy. Respirology 2015; 20:967-74. [PMID: 26094505 DOI: 10.1111/resp.12578] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/18/2015] [Accepted: 03/23/2015] [Indexed: 12/26/2022]
Abstract
BACKGROUND AND OBJECTIVE The development of novel technologies has increased the yield from transbronchial biopsies while preserving patient safety by guiding biopsies to the area of interest. Other technologies have helped identify pre-cancerous or sessile lesions in the endobronchial space by utilizing interactions between tissue and light at varying wavelengths. Probe-based confocal laser endomicroscopy (pCLE) is a new technology that encompasses the benefits of both guided biopsies and novel optical imaging in one device. This project compares pCLE images to the findings of light microscopy in non-small cell lung cancer (NSCLC). METHODS Patients who underwent bronchoscopies between July 2012 and January 2013 for evaluation of pulmonary lesions (transbronchial and endobronchial) were recruited. Histopathological images from malignant lesions were compared with the pCLE images obtained from the same area. The microscopic and pCLE images were reviewed side by side with the microscopic findings. RESULTS Images from pCLE correlate with some histopathological findings. pCLE changes seen in NSCLC consist of mottled elastin, septal studding and disorganization/fragmentation with increased friability. These changes also seem to correlate with degrees of differentiation. CONCLUSIONS pCLE can identify changes to the elastin composition of the airways and alveoli in lung cancer. These changes correlate with histopathology and may help indicate the presence of malignant changes in vivo.
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Affiliation(s)
- Adam S Wellikoff
- Section of Pulmonary, Critical Care, and Sleep Medicine, Interventional Pulmonary Program, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA
| | - Robert C Holladay
- Section of Pulmonary, Critical Care, and Sleep Medicine, Interventional Pulmonary Program, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA
| | - Gordon H Downie
- Interventional Pulmonary Program, Titus Regional Medical Center, Mt. Pleasant, Texas, USA
| | - Catherine S Chaudoir
- Department of Pathology, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA
| | - Luis Brandi
- Department of Pathology, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA
| | - Elba A Turbat-Herrera
- Department of Pathology, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA
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16
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McLaughlin RA, Noble PB, Sampson DD. Optical coherence tomography in respiratory science and medicine: from airways to alveoli. Physiology (Bethesda) 2015; 29:369-80. [PMID: 25180266 DOI: 10.1152/physiol.00002.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Optical coherence tomography is a rapidly maturing optical imaging technology, enabling study of the in vivo structure of lung tissue at a scale of tens of micrometers. It has been used to assess the layered structure of airway walls, quantify both airway lumen caliber and compliance, and image individual alveoli. This article provides an overview of the technology and reviews its capability to provide new insights into respiratory disease.
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Affiliation(s)
- Robert A McLaughlin
- Optical & Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Perth, Australia;
| | - Peter B Noble
- School of Anatomy, Physiology & Human Biology, and Centre for Neonatal Research & Education, School of Paediatrics and Child Health, The University of Western Australia, Crawley, Australia; and
| | - David D Sampson
- Optical & Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Perth, Australia; Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Perth, Australia
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17
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Scolaro L, Lorenser D, Madore WJ, Kirk RW, Kramer AS, Yeoh GC, Godbout N, Sampson DD, Boudoux C, McLaughlin RA. Molecular imaging needles: dual-modality optical coherence tomography and fluorescence imaging of labeled antibodies deep in tissue. BIOMEDICAL OPTICS EXPRESS 2015; 6:1767-81. [PMID: 26137379 PMCID: PMC4467702 DOI: 10.1364/boe.6.001767] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/06/2015] [Accepted: 04/14/2015] [Indexed: 05/04/2023]
Abstract
Molecular imaging using optical techniques provides insight into disease at the cellular level. In this paper, we report on a novel dual-modality probe capable of performing molecular imaging by combining simultaneous three-dimensional optical coherence tomography (OCT) and two-dimensional fluorescence imaging in a hypodermic needle. The probe, referred to as a molecular imaging (MI) needle, may be inserted tens of millimeters into tissue. The MI needle utilizes double-clad fiber to carry both imaging modalities, and is interfaced to a 1310-nm OCT system and a fluorescence imaging subsystem using an asymmetrical double-clad fiber coupler customized to achieve high fluorescence collection efficiency. We present, to the best of our knowledge, the first dual-modality OCT and fluorescence needle probe with sufficient sensitivity to image fluorescently labeled antibodies. Such probes enable high-resolution molecular imaging deep within tissue.
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Affiliation(s)
- Loretta Scolaro
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, & Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Dirk Lorenser
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, & Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Wendy-Julie Madore
- Centre d'optique, photonique et lasers, Department of Engineering Physics, Polytechnique Montréal, Montréal (QC), Canada
| | - Rodney W. Kirk
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, & Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Anne S. Kramer
- Centre for Medical Research, The Harry Perkins Institute of Medical Research and School of Chemistry & Biochemistry, The University of Western Australia, Crawley, Australia
| | - George C. Yeoh
- Centre for Medical Research, The Harry Perkins Institute of Medical Research and School of Chemistry & Biochemistry, The University of Western Australia, Crawley, Australia
| | - Nicolas Godbout
- Centre d'optique, photonique et lasers, Department of Engineering Physics, Polytechnique Montréal, Montréal (QC), Canada
| | - David D. Sampson
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, & Computer Engineering, The University of Western Australia, Crawley, Australia
- Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Crawley, Australia
| | - Caroline Boudoux
- Centre d'optique, photonique et lasers, Department of Engineering Physics, Polytechnique Montréal, Montréal (QC), Canada
| | - Robert A. McLaughlin
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, & Computer Engineering, The University of Western Australia, Crawley, Australia
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18
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Iftimia N, Maguluri G, Chang EW, Chang S, Magill J, Brugge W. Hand scanning optical coherence tomography imaging using encoder feedback. OPTICS LETTERS 2014; 39:6807-6810. [PMID: 25503002 DOI: 10.1364/ol.39.006807] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a new method for generating micron-scale OCT images of interstitial tissue with a hand scanning probe and a linear optical encoder that senses probe movement relative to a fixed reference point, i.e., tissue surface. Based on this approach, we demonstrate high resolution optical imaging of biological tissues through a very long biopsy needle. Minor artifacts caused by tissue noncompliance are corrected using a software algorithm which detects the simple repetition of the adjacent A-scans. This hand-scanning OCT imaging approach offers the physician the freedom to access imaging sites of interest repeatedly.
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19
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Milne S, King GG. Advanced imaging in COPD: insights into pulmonary pathophysiology. J Thorac Dis 2014; 6:1570-85. [PMID: 25478198 DOI: 10.3978/j.issn.2072-1439.2014.11.30] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 11/10/2014] [Indexed: 12/31/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) involves a complex interaction of structural and functional abnormalities. The two have long been studied in isolation. However, advanced imaging techniques allow us to simultaneously assess pathological processes and their physiological consequences. This review gives a comprehensive account of the various advanced imaging modalities used to study COPD, including computed tomography (CT), magnetic resonance imaging (MRI), and the nuclear medicine techniques positron emission tomography (PET) and single-photon emission computed tomography (SPECT). Some more recent developments in imaging technology, including micro-CT, synchrotron imaging, optical coherence tomography (OCT) and electrical impedance tomography (EIT), are also described. The authors identify the pathophysiological insights gained from these techniques, and speculate on the future role of advanced imaging in both clinical and research settings.
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Affiliation(s)
- Stephen Milne
- 1 The Woolcock Institute of Medical Research, Glebe, Sydney NSW 2037, Australia ; 2 Northern Clinical School, University of Sydney, NSW 2006, Australia ; 3 Northern and Central Clinical Schools, University of Sydney, NSW 2006, Australia ; 4 Department of Respiratory Medicine, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
| | - Gregory G King
- 1 The Woolcock Institute of Medical Research, Glebe, Sydney NSW 2037, Australia ; 2 Northern Clinical School, University of Sydney, NSW 2006, Australia ; 3 Northern and Central Clinical Schools, University of Sydney, NSW 2006, Australia ; 4 Department of Respiratory Medicine, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
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20
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Quirk BC, McLaughlin RA, Pagnozzi AM, Kennedy BF, Noble PB, Sampson DD. Optofluidic needle probe integrating targeted delivery of fluid with optical coherence tomography imaging. OPTICS LETTERS 2014; 39:2888-91. [PMID: 24978229 DOI: 10.1364/ol.39.002888] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We present an optofluidic optical coherence tomography (OCT) needle probe capable of modifying the local optical properties of tissue to improve needle-probe imaging performance. The side-viewing probe comprises an all-fiber-optic design encased in a hypodermic needle (outer diameter 720 μm) and integrates a coaxial fluid-filled channel, terminated by an outlet adjacent to the imaging window, allowing focal injection of fluid to a target tissue. This is the first fully integrated OCT needle probe design to incorporate fluid injection into the imaging mechanism. The utility of this probe is demonstrated in air-filled sheep lungs, where injection of small quantities of saline is shown, by local refractive index matching, to greatly improve image penetration through multiple layers of alveoli. 3D OCT images are correlated against histology, showing improvement in the capability to image lung structures such as bronchioles and blood vessels.
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21
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Akulian J, Feller-Kopman D, Lee H, Yarmus L. Advances in interventional pulmonology. Expert Rev Respir Med 2014; 8:191-208. [PMID: 24450415 DOI: 10.1586/17476348.2014.880053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Interventional pulmonology (IP) remains a rapidly expanding and evolving subspecialty focused on the diagnosis and treatment of complex diseases of the thorax. As the field continues to push the leading edge of medical technology, new procedures allow for novel minimally invasive approaches to old diseases including asthma, chronic obstructive pulmonary disease and metastatic or primary lung malignancy. In addition to technologic advances, IP has matured into a defined subspecialty, requiring formal training necessary to perform the advanced procedures. This need for advanced training has led to the need for standardization of training and the institution of a subspecialty board examination. In this review, we will discuss the dynamic field of IP as well as novel technologies being investigated or employed in the treatment of thoracic disease.
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Affiliation(s)
- Jason Akulian
- University of North Carolina, Pulmonary and Critical Care, Chapel Hill, CA, USA
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22
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Chang EW, Gardecki J, Pitman M, Wilsterman EJ, Patel A, Tearney GJ, Iftimia N. Low coherence interferometry approach for aiding fine needle aspiration biopsies. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:116005. [PMID: 25375634 PMCID: PMC4222708 DOI: 10.1117/1.jbo.19.11.116005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 10/13/2014] [Indexed: 05/06/2023]
Abstract
We present portable preclinical low-coherence interference (LCI) instrumentation for aiding fine needle aspiration biopsies featuring the second-generation LCI-based biopsy probe and an improved scoring algorithm for tissue differentiation. Our instrument and algorithm were tested on 38 mice with cultured tumor mass and we show the specificity, sensitivity, and positive predictive value of tumor detection of over 0.89, 0.88, and 0.96, respectively.
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Affiliation(s)
- Ernest W. Chang
- Physical Sciences, Inc., 20 New England Business Ctr. Drive, Andover, Massachusetts 01810, United States
| | - Joseph Gardecki
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom, Boston, Massachusetts 02114, United States
| | - Martha Pitman
- Massachusetts General Hospital, Department of Pathology, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Eric J. Wilsterman
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom, Boston, Massachusetts 02114, United States
| | - Ankit Patel
- Physical Sciences, Inc., 20 New England Business Ctr. Drive, Andover, Massachusetts 01810, United States
| | - Guillermo J. Tearney
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom, Boston, Massachusetts 02114, United States
| | - Nicusor Iftimia
- Physical Sciences, Inc., 20 New England Business Ctr. Drive, Andover, Massachusetts 01810, United States
- Address all correspondence to: Nicusor Iftimia, E-mail:
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23
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Yang X, Lorenser D, McLaughlin RA, Kirk RW, Edmond M, Simpson MC, Grounds MD, Sampson DD. Imaging deep skeletal muscle structure using a high-sensitivity ultrathin side-viewing optical coherence tomography needle probe. BIOMEDICAL OPTICS EXPRESS 2013; 5:136-48. [PMID: 24466482 PMCID: PMC3891326 DOI: 10.1364/boe.5.000136] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 11/22/2013] [Accepted: 11/30/2013] [Indexed: 05/16/2023]
Abstract
We have developed an extremely miniaturized optical coherence tomography (OCT) needle probe (outer diameter 310 µm) with high sensitivity (108 dB) to enable minimally invasive imaging of cellular structure deep within skeletal muscle. Three-dimensional volumetric images were acquired from ex vivo mouse tissue, examining both healthy and pathological dystrophic muscle. Individual myofibers were visualized as striations in the images. Degradation of cellular structure in necrotic regions was seen as a loss of these striations. Tendon and connective tissue were also visualized. The observed structures were validated against co-registered hematoxylin and eosin (H&E) histology sections. These images of internal cellular structure of skeletal muscle acquired with an OCT needle probe demonstrate the potential of this technique to visualize structure at the microscopic level deep in biological tissue in situ.
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Affiliation(s)
- Xiaojie Yang
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, and Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Dirk Lorenser
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, and Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Robert A. McLaughlin
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, and Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Rodney W. Kirk
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, and Computer Engineering, The University of Western Australia, Crawley, Australia
| | - Matthew Edmond
- Photon Factory, School of Chemical Sciences & Department of Physics, University of Auckland, Auckland, New Zealand
| | - M. Cather Simpson
- Photon Factory, School of Chemical Sciences & Department of Physics, University of Auckland, Auckland, New Zealand
| | - Miranda D. Grounds
- School of Anatomy, Physiology, and Human Biology, The University of Western Australia
| | - David D. Sampson
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic, and Computer Engineering, The University of Western Australia, Crawley, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Crawley, Australia
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24
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Yang X, Chin L, Klyen BR, Shavlakadze T, McLaughlin RA, Grounds MD, Sampson DD. Quantitative assessment of muscle damage in the mdx mouse model of Duchenne muscular dystrophy using polarization-sensitive optical coherence tomography. J Appl Physiol (1985) 2013; 115:1393-401. [DOI: 10.1152/japplphysiol.00265.2013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Minimally invasive, high-resolution imaging of muscle necrosis has the potential to aid in the assessment of diseases such as Duchenne muscular dystrophy. Undamaged muscle tissue possesses high levels of optical birefringence due to its anisotropic ultrastructure, and this birefringence decreases when the tissue undergoes necrosis. In this study, we present a novel technique to image muscle necrosis using polarization-sensitive optical coherence tomography (PS-OCT). From PS-OCT scans, our technique is able to quantify the birefringence in muscle tissue, generating an image indicative of the tissue ultrastructure, with areas of abnormally low birefringence indicating necrosis. The technique is demonstrated on excised skeletal muscles from exercised dystrophic mdx mice and control C57BL/10ScSn mice with the resulting images validated against colocated histological sections. The technique additionally gives a measure of the proportion (volume fraction) of necrotic tissue within the three-dimensional imaging field of view. The percentage necrosis assessed by this technique is compared against the percentage necrosis obtained from manual assessment of histological sections, and the difference between the two methods is found to be comparable to the interobserver variability of the histological assessment. This is the first published demonstration of PS-OCT to provide automated assessment of muscle necrosis.
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Affiliation(s)
- Xiaojie Yang
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia
| | - Lixin Chin
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia
| | - Blake R. Klyen
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia
| | - Tea Shavlakadze
- Skeletal Muscle Research Group, School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Western Australia, Australia; and
| | - Robert A. McLaughlin
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia
| | - Miranda D. Grounds
- Skeletal Muscle Research Group, School of Anatomy, Physiology & Human Biology, The University of Western Australia, Crawley, Western Australia, Australia; and
| | - David D. Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia
- Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Crawley, Western Australia, Australia
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25
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Namati E, Warger WC, Unglert CI, Eckert JE, Hostens J, Bouma BE, Tearney GJ. Four-dimensional visualization of subpleural alveolar dynamics in vivo during uninterrupted mechanical ventilation of living swine. BIOMEDICAL OPTICS EXPRESS 2013; 4:2492-506. [PMID: 24298409 PMCID: PMC3829543 DOI: 10.1364/boe.4.002492] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 08/24/2013] [Accepted: 08/28/2013] [Indexed: 05/04/2023]
Abstract
Pulmonary alveoli have been studied for many years, yet no unifying hypothesis exists for their dynamic mechanics during respiration due to their miniature size (100-300 μm dimater in humans) and constant motion, which prevent standard imaging techniques from visualizing four-dimensional dynamics of individual alveoli in vivo. Here we report a new platform to image the first layer of air-filled subpleural alveoli through the use of a lightweight optical frequency domain imaging (OFDI) probe that can be placed upon the pleura to move with the lung over the complete range of respiratory motion. This device enables in-vivo acquisition of four-dimensional microscopic images of alveolar airspaces (alveoli and ducts), within the same field of view, during continuous ventilation without restricting the motion or modifying the structure of the alveoli. Results from an exploratory study including three live swine suggest that subpleural alveolar air spaces are best fit with a uniform expansion (r (2) = 0.98) over a recruitment model (r (2) = 0.72). Simultaneously, however, the percentage change in volume shows heterogeneous alveolar expansion within just a 1 mm x 1 mm field of view. These results signify the importance of four-dimensional imaging tools, such as the device presented here. Quantification of the dynamic response of the lung during ventilation may help create more accurate modeling techniques and move toward a more complete understanding of alveolar mechanics.
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Affiliation(s)
- Eman Namati
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
- Co-first authors. These authors contributed equally to this work
| | - William C. Warger
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
- Co-first authors. These authors contributed equally to this work
| | - Carolin I. Unglert
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
- Air Liquide Centre de Recherche Claude-Delorme, Medical Gases Group, 1 Chemin de la Porte des Loges, Les-Loges-en-Josas, France
| | - Jocelyn E. Eckert
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
| | | | - Brett E. Bouma
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
- Harvard-MIT Division of Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 USA
| | - Guillermo J. Tearney
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Blossom St., BAR-714, Boston, MA 02114 USA
- Harvard-MIT Division of Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA 02114 USA
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26
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Pagnozzi AM, Kirk RW, Kennedy BF, Sampson DD, McLaughlin RA. Automated quantification of lung structures from optical coherence tomography images. BIOMEDICAL OPTICS EXPRESS 2013; 4:2383-2395. [PMID: 24298402 PMCID: PMC3829535 DOI: 10.1364/boe.4.002383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 05/30/2023]
Abstract
Characterization of the size of lung structures can aid in the assessment of a range of respiratory diseases. In this paper, we present a fully automated segmentation and quantification algorithm for the delineation of large numbers of lung structures in optical coherence tomography images, and the characterization of their size using the stereological measure of median chord length. We demonstrate this algorithm on scans acquired with OCT needle probes in fresh, ex vivo tissues from two healthy animal models: pig and rat. Automatically computed estimates of lung structure size were validated against manual measures. In addition, we present 3D visualizations of the lung structures using the segmentation calculated for each data set. This method has the potential to provide an in vivo indicator of structural remodeling caused by a range of respiratory diseases, including chronic obstructive pulmonary disease and pulmonary fibrosis.
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Affiliation(s)
- Alex M. Pagnozzi
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Rodney W. Kirk
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Brendan F. Kennedy
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - David D. Sampson
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Robert A. McLaughlin
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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27
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Zander DS. Volumetric optical frequency domain imaging: building a new lexicon. Chest 2013; 143:10-12. [PMID: 23276839 DOI: 10.1378/chest.12-1864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Dani S Zander
- Department of Pathology, Penn State Milton S. Hershey Medical Center/Penn State College of Medicine, Hershey, PA.
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28
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Unglert CI, Warger WC, Hostens J, Namati E, Birngruber R, Bouma BE, Tearney GJ. Validation of two-dimensional and three-dimensional measurements of subpleural alveolar size parameters by optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:126015. [PMID: 23235834 PMCID: PMC3519489 DOI: 10.1117/1.jbo.17.12.126015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Optical coherence tomography (OCT) has been increasingly used for imaging pulmonary alveoli. Only a few studies, however, have quantified individual alveolar areas, and the validity of alveolar volumes represented within OCT images has not been shown. To validate quantitative measurements of alveoli from OCT images, we compared the cross-sectional area, perimeter, volume, and surface area of matched subpleural alveoli from microcomputed tomography (micro-CT) and OCT images of fixed air-filled swine samples. The relative change in size between different alveoli was extremely well correlated (r>0.9, P<0.0001), but OCT images underestimated absolute sizes compared to micro-CT by 27% (area), 7% (perimeter), 46% (volume), and 25% (surface area) on average. We hypothesized that the differences resulted from refraction at the tissue-air interfaces and developed a ray-tracing model that approximates the reconstructed alveolar size within OCT images. Using this model and OCT measurements of the refractive index for lung tissue (1.41 for fresh, 1.53 for fixed), we derived equations to obtain absolute size measurements of superellipse and circular alveoli with the use of predictive correction factors. These methods and results should enable the quantification of alveolar sizes from OCT images in vivo.
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Affiliation(s)
- Carolin I Unglert
- Harvard Medical School and Massachusetts General Hospital, Wellman Center for Photomedicine, 40 Parkman Street, RSL 160, Boston, Massachusetts 02114, USA.
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