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Needle-based refractive index measurement using low-coherence interferometry

Adam M. Zysk, Steven G. Adie, Julian J. Armstrong, Matthew S. Leigh, Alexandre Paduch, David D. Sampson, Freddy T. Nguyen, Stephen A. Boppart
2007 Optics Letters  
We present a novel needle-based device for the measurement of refractive index and scattering using lowcoherence interferometry.  ...  Coupled to the sample arm of an optical coherence tomography system, the device detects the scattering response of, and optical path length through, a sample residing in a fixed-width channel.  ...  The RI error bars are due to beam position and sample width measurement uncertainties and the reflector position error bars indicate the standard deviation.  ... 
doi:10.1364/ol.32.000385 pmid:17356661 fatcat:ikvjkmkoyjfbxbrqrzez742l3m

Sources of Absorption and Scattering Contrast for Near-Infrared Optical Mammography

Albert E. Cerussi, Andrew J. Berger, Frederic Bevilacqua, Natasha Shah, Dorota Jakubowski, John Butler, Randall F. Holcombe, Bruce J. Tromberg
2001 Academic Radiology  
A seven-wavelength frequency-domain photon migration probe was used to perform noninvasive NIR measurements in the breasts of 28 healthy women, both pre-and postmenopausal, aged 18 -64 years.  ...  Substantial quantitative differences were observed in both absorption and scattering spectra of breast as a function of subject age.  ...  Measurements were performed with a hand-held probe (close-up at bottom ofFigure)that contained the APD and a source optical fiber.  ... 
doi:10.1016/s1076-6332(03)80529-9 pmid:11249084 fatcat:5ssuro5aenb47c6bv2t6rcn4eq

Diffuse reflectance spectroscopy of epithelial tissue with a smart fiber-optic probe

Bing Yu, Amy Shah, Vivek K. Nagarajan, Daron G. Ferris
2014 Biomedical Optics Express  
Diffuse reflectance spectroscopy (DRS) with a fiber-optic probe can noninvasively quantify the optical properties of epithelial tissues and has shown the potential as a cost-effective, fast and sensitive  ...  However, current DRS systems are susceptible to several sources of systematic and random errors, such as uncontrolled probe-to-tissue pressure and lack of a real-time calibration that can significantly  ...  Acknowledgments This research was supported by the National Institutes of Health, National Institute of Biomedical Imaging and Bioengineering, grant No. R03EB012210.  ... 
doi:10.1364/boe.5.000675 pmid:24688805 pmcid:PMC3959852 fatcat:ffsphs6b35ffhbm3cgsjucrcfe

Combined Non-Invasive Optical Oximeter and Flowmeter with Basic Metrological Equipment

Andrey Tarasov, Denis Lapitan, Dmitry Rogatkin
2022 Photonics  
The combination of two related optical diagnostic techniquesa tissue oximetry, including a cerebral one, and a fluctuation flowmetry on a single hardware platform—was used.  ...  , which all together lead to large uncertainties and inaccuracies in diagnostic data.  ...  technical requirements for noninvasive spectrophotometric diagnostic devices [13] .  ... 
doi:10.3390/photonics9060392 fatcat:wu73wzcptvdvfj7q4kjx7vx7yu

Development of calibration techniques for ultrasonic hydrophone probes in the frequency range from 1 to 100MHz

S. Umchid, R. Gopinath, K. Srinivasan, P.A. Lewin, A.S. Daryoush, L. Bansal, M. El-Sherif
2009 Ultrasonics  
The results indicated that the focal plane area as determined by -3dB isobar of the HIFU source was 3.2 mm 2 (about 2 mm in diameter).  ...  variations, averaging errors, instability of the acoustic and laser (fiber optic) sources, intrinsic noise levels of the hydrophone and the fiber optic sensors assembly, and environmental uncertainties  ...  Improvement of the sensitivity of the FO hydrophone probe: As noted earlier for the measurement of acoustic output produced by diagnostic imaging machines of a variety of diagnostic fields, the current  ... 
doi:10.1016/j.ultras.2008.09.011 pmid:19110289 pmcid:PMC2677298 fatcat:6ztwubhu5rhmtniyyxof3kf7ke

Parallel guidance endoscopic optical coherence tomography system for internal diagnosis through active cannulas

Suhyeon Gim, Hyowon Moon, Hyun-Joon Shin, Deukhee Lee, Sungchul Kang, Keri Kim
2014 Optical Engineering: The Journal of SPIE  
Thus, it could be implemented for various types of noninvasive diagnoses in situations involving small entrances or crooked passage to a target.  ...  A parallel guidance endoscopic optical coherence tomography (OCT) system is proposed for minimally invasive internal inspection of inner organs or complex structures for diagnosis.  ...  The authors are also greatly thankful for eagerly working students Taeyoung Choi and Xiao Li with their elaborate experiments and consideration into the results.  ... 
doi:10.1117/1.oe.53.8.084105 fatcat:6fypkrm76bhjvkmzfnkkjhxwmy

Thin photothermal endoscope for biomedical applications

Sreekumar Kaiplavil
2013 Journal of Biomedical Optics  
The device is slidable through a syringe needle and PT analysis of exposed organs with limited accessibility for conventional PT techniques, and constricted regions can be examined noninvasively.  ...  The technique has the unique advantage that the pump laser delivery fiber itself acts as the thermal wave sensor, which is a Bragg grating.  ...  Acknowledgments The author gratefully acknowledges a start-up cluster research grant that supported this research.  ... 
doi:10.1117/1.jbo.18.9.097008 fatcat:2bhizq4h7rfbnguidp3fo367um

Noninvasive diffuse optical measurement of blood flow and blood oxygenation for monitoring radiation therapy in patients with head and neck tumors: a pilot study

Ulas Sunar, Harry Quon, Turgut Durduran, Jun Zhang, Juan Du, Chao Zhou, Guoqiang Yu, Regine Choe, Alex Kilger, Robert Lustig, Laurie Loevner, Shoko Nioka (+2 others)
2006 Journal of Biomedical Optics  
This pilot study explores the potential of noninvasive diffuse correlation spectroscopy ͑DCS͒ and diffuse reflectance spectroscopy ͑DRS͒ for monitoring early relative blood flow ͑rBF͒, tissue oxygen saturation  ...  measured before and during the chemo-radiation therapy period.  ...  Acknowledgments This research is supported by National Institutes of Health grants HL-077699-01 and CA-87971. We thank S. Kim and H. Poptani for useful discussions. We also thank the Radiation  ... 
doi:10.1117/1.2397548 pmid:17212544 fatcat:ue23kccc7fbtnlf3534glrkyse

A Phonocardiographic-Based Fiber-Optic Sensor and Adaptive Filtering System for Noninvasive Continuous Fetal Heart Rate Monitoring

Radek Martinek, Jan Nedoma, Marcel Fajkus, Radana Kahankova, Jaromir Konecny, Petr Janku, Stanislav Kepak, Petr Bilik, Homer Nazeran
2017 Sensors  
This paper focuses on the design, realization, and verification of a novel phonocardiographicbased fiber-optic sensor and adaptive signal processing system for noninvasive continuous fetal heart rate (  ...  Based on the analysis of real measurement data, we developed a simplified dynamic model for the generation and distribution of heart sounds throughout the human body.  ...  Homer Nazeran and Petr Janku critically evaluated the quality of the research data and experimental methods used to generate/acquire them as well as the soundness/validity of the scientific and engineering  ... 
doi:10.3390/s17040890 pmid:28420215 pmcid:PMC5426540 fatcat:hqitriwjxbep5lbk42rberu7hm

Measurement of the reduced scattering coefficient of turbid media using single fiber reflectance spectroscopy: fiber diameter and phase function dependence

S. C. Kanick, U. A. Gamm, M. Schouten, H. J. C. M. Sterenborg, D. J. Robinson, A. Amelink
2011 Biomedical Optics Express  
This calibrated technique provides accurate estimates of μ s over a wide range ([0.05 − 8] mm −1 ) for a range of d f ib ([0.2 − 1] mm).  ...  This paper presents a relationship between the intensity collected by a single fiber reflectance device (R SF ) and the fiber diameter (d f ib ) and the reduced scattering coefficient (μ s ) and phase  ...  effect of and variations in probe-spectralon distance utilized in our previous calibration technique (as noted in Section 2.3).  ... 
doi:10.1364/boe.2.001687 pmid:21698029 pmcid:PMC3114234 fatcat:jt3aryv4kje2vdfymaf4uglpvq

Enabling instrumentation and technology for 21st century light sources

J.M. Byrd, T.J. Shea, P. Denes, P. Siddons, D. Attwood, F. Kaertner, L. Moog, Y. Li, A. Sakdinawat, R. Schlueter
2010 Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment  
We describe progress and potential in three areas: attosecond instrumentation, photon detectors for user experiments, and insertion devices.  ...  Light Sources held in Gaithersburg, MD September 15-17, 2009.  ...  laser, seed lasers as well as potential probe and diagnostic lasers.  ... 
doi:10.1016/j.nima.2010.06.244 fatcat:bvn5sg4ggbgtxchanewzvkx7gm

The Effect of Probe Pressure on In Vivo Single Fiber Reflectance Spectroscopy

Sanaz Hariri Tabrizi, Ali Akbar Shakibaei
2016 Journal of lasers in medical sciences  
It can be used to diagnose different diseases such as malignancy and pre-cancerous conditions. The measurement is done with a fiber optic probe in contact with the tissue surface.  ...  Conclusion: SFRS can be used as a reliable diagnostic tool in clinics.  ...  Also, we would like to thank Shahid Beheshti University staff and faculty for providing required facilities for the study, especially Dr. SMR Aghamiri.  ... 
doi:10.15171/jlms.2016.41 pmid:28491258 pmcid:PMC5415500 fatcat:svz4h6bawfau5i3jcnibubyvfm

Fiber Optic Velocity Interferometry

Barry T. Neyer, Barry T. Neyer
1989 High Bandwidth Analog Applications of Photonics II  
This paper explores the use of a new velocity measurement technique that has several advantages over existing techniques. It uses an optical fiber to carry coherent light to and from a moving target.  ...  This technique can measure velocities up to 10 km/s, is accurate, portable, and completely noninvasive.  ...  A velocity diagnostic constructed of fiber optic components would overcome many of the problems with the presently used techniques.  ... 
doi:10.1117/12.959686 fatcat:zvfejdzxl5evhksyjkv35yqewq

Quantification of the optical properties of two-layered turbid media by simultaneously analyzing the spectral and spatial information of steady-state diffuse reflectance spectroscopy

Te-Yu Tseng, Chun-Yu Chen, Yi-Shan Li, Kung-Bin Sung
2011 Biomedical Optics Express  
top layer thickness in comparison to methods fitting reflectance spectra measured with a single source-detector separation or fitting spatially-resolved reflectance at a single wavelength.  ...  Results of fitting simulated data showed that simultaneously considering the spatial and spectral information in the inversion process improves the accuracies of estimating the optical properties and the  ...  Acknowledgments The authors thank the National Science Council of Taiwan for financial support (NSC 99-2628-E-002-014) of this research.  ... 
doi:10.1364/boe.2.000901 pmid:21483612 pmcid:PMC3072129 fatcat:btyurbgznnfshobgc7yjhkwqhq

Single fiber reflectance spectroscopy on cervical premalignancies: the potential for reduction of the number of unnecessary biopsies

Sanaz Hariri Tabrizi, S. Mahmoud Reza Aghamiri, Farah Farzaneh, Arjen Amelink, Henricus J. C. M. Sterenborg
2013 Journal of Biomedical Optics  
SFR spectroscopy shows promise as a noninvasive, real-time method to guide the clinician in reducing the number of unnecessary biopsies.  ...  We have assessed the value of single fiber reflectance (SFR) spectroscopy in prediction of cervical squamous intraepithelial lesions (SIL).  ...  Acknowledgments This work was funded in part by the Ministry of Science, Research and Technology of Iran.  ... 
doi:10.1117/1.jbo.18.1.017002 pmid:23292613 fatcat:uc4qapz3nrh6dgls67ggwji5lu
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