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Khurana L, Keppeler D, Jablonski L, Moser T. Model-based prediction of optogenetic sound encoding in the human cochlea by future optical cochlear implants. Comput Struct Biotechnol J 2022; 20:3621-3629. [PMID: 35860414 PMCID: PMC9283772 DOI: 10.1016/j.csbj.2022.06.061] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/28/2022] [Accepted: 06/28/2022] [Indexed: 01/17/2023] Open
Abstract
When hearing fails, electrical cochlear implants (eCIs) partially restore hearing by direct stimulation of spiral ganglion neurons (SGNs). As light can be better confined in space than electrical current, optical CIs (oCIs) provide more spectral information promising a fundamental improvement of hearing restoration by cochlear implants. Here, we turned to computer modelling for predicting the outcome of optogenetic hearing restoration by future oCIs in humans. We combined three-dimensional reconstruction of the human cochlea with ray-tracing simulation of emission from LED or laser-coupled waveguide emitters of the oCI. Irradiance was read out at the somata of SGNs. The irradiance values reached with waveguides were about 14 times higher than with LEDs, at the same radiant flux of the emitter. Moreover, waveguides outperformed LEDs regarding spectral selectivity. oCIs with either emitter type showed greater spectral selectivity when compared to eCI. In addition, modeling the effects of the source-to-SGN distance, orientation of the sources and impact of scar tissue further informs the development of optogenetic hearing restoration.
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Affiliation(s)
- Lakshay Khurana
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
- Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany
- Auditory Neuroscience & Synaptic Nanophysiology Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Göttingen Graduate Center for Neurosciences, Biophysics, and Molecular Biosciences (GGNB), University of Göttingen, Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
| | - Daniel Keppeler
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
- Auditory Neuroscience & Synaptic Nanophysiology Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
| | - Lukasz Jablonski
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
- Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
- Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany
- Auditory Neuroscience & Synaptic Nanophysiology Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence “Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells” (MBExC), University of Göttingen, Göttingen, Germany
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2
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Kallepalli A, Halls J, James DB, Richardson MA. An ultrasonography-based approach for tissue modelling to inform photo-therapy treatment strategies. JOURNAL OF BIOPHOTONICS 2022; 15:e202100275. [PMID: 35044094 DOI: 10.1002/jbio.202100275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Currently, diagnostic medicine uses a multitude of tools ranging from ionising radiation to histology analysis. With advances in piezoelectric crystal technology, high-frequency ultrasound imaging has developed to achieve comparatively high resolution without the drawbacks of ionising radiation. This research proposes a low-cost, non-invasive and real-time protocol for informing photo-therapy procedures using ultrasound imaging. We combine currently available ultrasound procedures with Monte Carlo methods for assessing light transport and photo-energy deposition in the tissue. The measurements from high-resolution ultrasound scans are used as input for optical simulations. Consequently, this provides a pipeline that will inform medical practitioners for better therapy strategy planning. While validating known inferences of light transport through biological tissue, our results highlight the range of information such as temporal monitoring and energy deposition at varying depths. This process also retains the flexibility of testing various wavelengths for individual-specific geometries and anatomy.
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Affiliation(s)
- Akhil Kallepalli
- School of Physics and Astronomy, University of Glasgow, Glasgow, UK
| | - James Halls
- Department of Radiology, The Great Western Hospital, Swindon, UK
| | - David B James
- Centre for Electronic Warfare, Information and Cyber, Cranfield University, Defence Academy of the UK, Shrivenham, UK
| | - Mark A Richardson
- Centre for Electronic Warfare, Information and Cyber, Cranfield University, Defence Academy of the UK, Shrivenham, UK
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Agarwal A, Tan X, Xu Y, Richter CP. Channel Interaction During Infrared Light Stimulation in the Cochlea. Lasers Surg Med 2021; 53:986-997. [PMID: 33476051 DOI: 10.1002/lsm.23360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 10/21/2020] [Accepted: 11/07/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND OBJECTIVES The number of perceptually independent channels to encode acoustic information is limited in contemporary cochlear implants (CIs) because of the current spread in the tissue. It has been suggested that neighboring electrodes have to be separated in humans by a distance of more than 2 mm to eliminate significant overlap of the electric current fields and subsequent interaction between the channels. It has also been argued that an increase in the number of independent channels could improve CI user performance in challenging listening environments, such as speech in noise, tonal languages, or music perception. Optical stimulation has been suggested as an alternative modality for neural stimulation because it is spatially selective. This study reports the results of experiments designed to quantify the interaction between neighboring optical sources in the cochlea during stimulation with infrared radiation. STUDY DESIGN/MATERIALS AND METHODS In seven adult albino guinea pigs, a forward masking method was used to quantify the interaction between two neighboring optical sources during stimulation. Two optical fibers were placed through cochleostomies into the scala tympani of the basal cochlear turn. The radiation beams were directed towards different neuron populations along the spiral ganglion. Optically evoked compound action potentials were recorded for different radiant energies and distances between the optical fibers. The outcome measure was the radiant energy of a masker pulse delivered 3 milliseconds before a probe pulse to reduce the response evoked by the probe pulse by 3 dB. Results were compared for different distances between the fibers placed along the cochlea. RESULTS The energy required to reduce the probe's response by 3 dB increased by 20.4 dB/mm and by 26.0 dB/octave. The inhibition was symmetrical for the masker placed basal to the probe (base-to-apex) and the masker placed apical to the probe (apex-to-base). CONCLUSION The interaction between neighboring optical sources during infrared laser stimulation is less than the interaction between neighboring electrical contacts during electrical stimulation. Previously published data for electrical stimulation reported an average current spread in human and cat cochleae of 2.8 dB/mm. With the increased number of independent channels for optical stimulation, it is anticipated that speech and music performance will improve. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
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Affiliation(s)
- Aditi Agarwal
- Department of Otolaryngology, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Searle 12-561, Chicago, Illinois, 60611
| | - Xiaodong Tan
- Department of Otolaryngology, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Searle 12-561, Chicago, Illinois, 60611
| | - Yingyue Xu
- Department of Otolaryngology, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Searle 12-561, Chicago, Illinois, 60611
| | - Claus-Peter Richter
- Department of Otolaryngology, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Searle 12-561, Chicago, Illinois, 60611.,Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Tech E310, Evanston, Illinois, 60208.,Department of Communication Sciences and Disorders, Northwestern University, Evanston, Illinois, 60208.,Department of Communication Sciences and Disorders, The Hugh Knowles Center, Northwestern University, Evanston, Illinois, 60208
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4
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Romito M, Pu Y, Stankovic KM, Psaltis D. Imaging hair cells through laser-ablated cochlear bone. BIOMEDICAL OPTICS EXPRESS 2019; 10:5974-5988. [PMID: 31799058 PMCID: PMC6865115 DOI: 10.1364/boe.10.005974] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/29/2019] [Accepted: 10/24/2019] [Indexed: 05/04/2023]
Abstract
We report an innovative technique for the visualization of cells through an overlying scattering medium by combining femtosecond laser bone ablation and two-photon excitation fluorescence (TPEF) microscopy. We demonstrate the technique by imaging hair cells in an intact mouse cochlea ex vivo. Intracochlear imaging is important for the assessment of hearing disorders. However, the small size of the cochlea and its encasement in the densest bone in the body present challenging obstacles, preventing the visualization of the intracochlear microanatomy using standard clinical imaging modalities. The controlled laser ablation reduces the optical scattering of the cochlear bone while the TPEF allows visualization of individual cells behind the bone. We implemented optical coherence tomography (OCT) simultaneously with the laser ablation to enhance the precision of the ablation and prevent inadvertent damage to the cells behind the bone.
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Affiliation(s)
- Marilisa Romito
- Optics Laboratory, School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ye Pu
- Optics Laboratory, School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Konstantina M. Stankovic
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School and Massachusetts Eye and Ear, Boston, MA 02114, USA
| | - Demetri Psaltis
- Optics Laboratory, School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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Wrobel C, Dieter A, Huet A, Keppeler D, Duque-Afonso CJ, Vogl C, Hoch G, Jeschke M, Moser T. Optogenetic stimulation of cochlear neurons activates the auditory pathway and restores auditory-driven behavior in deaf adult gerbils. Sci Transl Med 2019; 10:10/449/eaao0540. [PMID: 29997248 DOI: 10.1126/scitranslmed.aao0540] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 11/17/2017] [Accepted: 06/19/2018] [Indexed: 12/26/2022]
Abstract
Cochlear implants partially restore hearing via direct electrical stimulation of spiral ganglion neurons (SGNs). However, spread of excitation from each electrode limits spectral coding. We explored the use of optogenetics to deliver spatially restricted and cell-specific excitation in the cochlea of adult Mongolian gerbils. Adeno-associated virus carrying the gene encoding the light-sensitive calcium translocating channelrhodopsin (CatCh) was injected into the cochlea of adult gerbils. SGNs in all cochlea turns showed stable and long-lasting CatCh expression, and electrophysiological recording from single SGNs showed that light stimulation up to few hundred Hertz induced neuronal firing. We characterized the light-induced activity in the auditory pathway by electrophysiological and behavioral analysis. Light- and sound-induced auditory brainstem responses showed similar kinetics and amplitude. In normal hearing adult gerbils, optical cochlear implants elicited stable optical auditory brainstem responses over a period of weeks. In normal hearing animals, light stimulation cued avoidance behavior that could be reproduced by subsequent acoustic stimulation, suggesting similar perception of light and acoustic stimuli. Neurons of the primary auditory cortex of normal hearing adult gerbils responded with changes in firing rates with increasing light intensity. In deaf adult gerbils, light stimulation generated auditory responses and cued avoidance behavior indicating partial restoration of auditory function. Our data show that optogenetic cochlear stimulation achieved good temporal fidelity with low light intensities in an adult rodent model, suggesting that optogenetics might be used to develop cochlear implants with improved restorative capabilities.
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Affiliation(s)
- Christian Wrobel
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Collaborative Research Center 889, University of Göttingen, 37075 Göttingen, Germany.,Department of Otorhinolaryngology, Head and Neck Surgery, Ruhr University Bochum, St. Elisabeth Hospital, 44787 Bochum, Germany
| | - Alexander Dieter
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Göttingen Graduate School for Neurosciences and Molecular Biosciences, University of Göttingen, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany
| | - Antoine Huet
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany
| | - Daniel Keppeler
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Göttingen Graduate School for Neurosciences and Molecular Biosciences, University of Göttingen, 37075 Göttingen, Germany
| | - Carlos J Duque-Afonso
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Göttingen Graduate School for Neurosciences and Molecular Biosciences, University of Göttingen, 37075 Göttingen, Germany
| | - Christian Vogl
- Collaborative Research Center 889, University of Göttingen, 37075 Göttingen, Germany.,Presynaptogenesis and Intracellular Transport in Hair Cells Group, Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Gerhard Hoch
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany.,Collaborative Research Center 889, University of Göttingen, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany
| | - Marcus Jeschke
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany. .,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany. .,Collaborative Research Center 889, University of Göttingen, 37075 Göttingen, Germany.,Göttingen Graduate School for Neurosciences and Molecular Biosciences, University of Göttingen, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany.,Bernstein Center for Computational Neuroscience, University of Göttingen, 37077 Göttingen, Germany.,Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University of Göttingen, 37075 Göttingen, Germany
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6
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White SM, Valdebran M, Kelly KM, Choi B. Simultaneous Blood Flow Measurement and Dermoscopy of Skin Lesions Using Dual-Mode Dermascope. Sci Rep 2018; 8:16941. [PMID: 30446685 PMCID: PMC6240112 DOI: 10.1038/s41598-018-35107-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/18/2018] [Indexed: 11/13/2022] Open
Abstract
Dermascopes are commonly utilized for the qualitative visual inspection of skin lesions. While automated image processing techniques and varied illumination strategies have been used to aid in structural analysis of lesions, robust quantification of functional information is largely unknown. To address this knowledge gap, we have developed a compact, handheld dermascope that enables real-time blood flow measurements of skin during conventional visual inspection. In-vitro characterization demonstrated that the dermascope is capable of quantifying changes in flow across a physiologically relevant range even when used in a handheld manner with clinic lighting and dermascope LEDs on. In a small pilot clinical study, we demonstrated the dermascope’s ability to detect flow differences between two distinct lesion types.
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Affiliation(s)
- Sean M White
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California, 92612, USA
| | - Manuel Valdebran
- Department of Dermatology, University of California, Irvine, California, 92697, USA
| | - Kristen M Kelly
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California, 92612, USA.,Department of Dermatology, University of California, Irvine, California, 92697, USA.,Department of Surgery, University of California, Irvine, California, 92697, USA
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California, 92612, USA. .,Department of Surgery, University of California, Irvine, California, 92697, USA. .,Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, California, 92697, USA. .,Department of Biomedical Engineering, University of California, Irvine, California, 92697, USA.
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7
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Hu S, Azorin-Peris V, Zheng J. Opto-physiological modeling applied to photoplethysmographic cardiovascular assessment. JOURNAL OF HEALTHCARE ENGINEERING 2014; 4:505-28. [PMID: 24287429 DOI: 10.1260/2040-2295.4.4.505] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This paper presents opto-physiological (OP) modeling and its application in cardiovascular assessment techniques based on photoplethysmography (PPG). Existing contact point measurement techniques, i.e., pulse oximetry probes, are compared with the next generation non-contact and imaging implementations, i.e., non-contact reflection and camera-based PPG. The further development of effective physiological monitoring techniques relies on novel approaches to OP modeling that can better inform the design and development of sensing hardware and applicable signal processing procedures. With the help of finite-element optical simulation, fundamental research into OP modeling of photoplethysmography is being exploited towards the development of engineering solutions for practical biomedical systems. This paper reviews a body of research comprising two OP models that have led to significant progress in the design of transmission mode pulse oximetry probes, and approaches to 3D blood perfusion mapping for the interpretation of cardiovascular performance.
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Affiliation(s)
- Sijung Hu
- School of Electronic, Electrical and Systems Engineering, Loughborough University, Loughborough Leicestershire LE11 3TU, UK
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8
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Moreno LE, Rajguru SM, Matic AI, Yerram N, Robinson AM, Hwang M, Stock S, Richter CP. Infrared neural stimulation: beam path in the guinea pig cochlea. Hear Res 2011; 282:289-302. [PMID: 21763410 DOI: 10.1016/j.heares.2011.06.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 06/23/2011] [Accepted: 06/25/2011] [Indexed: 11/26/2022]
Abstract
It has been demonstrated that INS can be utilized to stimulate spiral ganglion cells in the cochlea. Although neural stimulation can be achieved without direct contact of the radiation source and the tissue, the presence of fluids or bone between the target structure and the radiation source may lead to absorption or scattering of the radiation, which may limit the efficacy of INS. The present study demonstrates the neural structures in the radiation beam path that can be stimulated. Histological reconstructions and microCT of guinea pig cochleae stimulated with an infrared laser suggest that the orientation of the beam from the optical fiber determined the site of stimulation in the cochlea. Best frequencies of the INS-evoked neural responses obtained from the central nucleus of the inferior colliculus matched the histological sites in the spiral ganglion.
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Affiliation(s)
- Laura E Moreno
- Department of Otolaryngology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
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9
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Peris VA, Hu S. Validation of a Monte Carlo platform for the optical modelling of pulse oximetry. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1742-6596/85/1/012027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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10
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Burch S, Bogaards A, Siewerdsen J, Moseley D, Yee A, Finkelstein J, Weersink R, Wilson BC, Bisland SK. Photodynamic therapy for the treatment of metastatic lesions in bone: studies in rat and porcine models. JOURNAL OF BIOMEDICAL OPTICS 2005; 10:034011. [PMID: 16229655 DOI: 10.1117/1.1921887] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This study represents the first reported use of photodynamic therapy (PDT) for metastatic bone lesions and specifically, as a treatment for spinal metastases. A model of bone metastasis in rat confirmed the efficacy of benzoporphyrin derivative-monoacid-mediated PDT for treating lesions within the spine and appendicular bone. Fluorimetry confirmed the selective accumulation of drug into the tumor(s) at 3 h post-injection. 48 h post-light delivery into the vertebral body of the rat spine loss of bioluminescent signal and histological analyses of sectioned spine confirmed MT-1 tumor cell kill in vivo as previously confirmed in vitro using an established cell viability assay. Porcine vertebrae provided a model comparable to that of human for light propagation and PDT response. Histological examination of vertebrae 48 h post-PDT revealed a necrotic radius of 0.6 cm with an average fluence rate of 4.3 mW/cm2. Non-necrotic tissue damage was evident up to 2 cm out from the treatment fiber. Results support the application of PDT to the treatment of primary or metastatic lesions within bone.
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Affiliation(s)
- S Burch
- Ontario Cancer Institute, University Health Network, 610 University Avenue, Toronto, Ontario, Canada M5G 2M9
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Pifferi A, Torricelli A, Taroni P, Bassi A, Chikoidze E, Giambattistelli E, Cubeddu R. Optical biopsy of bone tissue: a step toward the diagnosis of bone pathologies. JOURNAL OF BIOMEDICAL OPTICS 2004; 9:474-480. [PMID: 15189084 DOI: 10.1117/1.1691029] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In vivo absorption and reduced scattering spectra of the human calcaneous from 650 to 1000 nm were assessed using a laboratory system for time-resolved transmittance spectroscopy. Measurements were performed on the calcaneous of seven female volunteers ranging from 26 to 82 years of age. The analysis of the absorption spectra, using a linear combination of the key tissue absorbers (bone mineral, water, lipids, oxy- and deoxyhemoglobin), revealed a general decrease in bone mineral content and an increase in lipids with age, which is in agreement with the aging transformations that occur in bone tissues. The scattering spectra were less effective in detecting such changes in older subjects, showing only a minor decrease in the coefficient for these subjects. The capability to noninvasively quantify bone tissue composition suggests a possible use of optical biopsy for the diagnosis of bone pathologies such as osteoporosis, which are characterized by a progressive reduction and transformation of the mineral in the bone matrix.
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Affiliation(s)
- Antonio Pifferi
- ULTRAS-INFM and IFN-CNR, Dipartimento di Fisica- Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy.
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