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Biomedical Optics Express

H Subramanian, P Viswanathan, L Cherkezyan, R Iyengar, S Rozhok, M Verleye, J Derbas, J Czarnecki, H K Roy, V Backman
Lung cancer is the leading cause of cancer deaths in the U.S. with survival dramatically depending on stage at diagnosis. We had earlier reported that nanocytology of buccal cells can accurately risk-stratify smokers for the presence of early and late-stage lung cancer. To translate the technique into clinical practice, standardization of operating procedures is necessary to consistently yield precise and repeatable results. Here, we develop and validate simple, robust, and easily implementable procedures for specimen collection, processing, etc...
September 1, 2016: Biomedical Optics Express
James A Guggenheim, Ilaria Bargigia, Andrea Farina, Antonio Pifferi, Hamid Dehghani
A novel straightforward, accessible and efficient approach is presented for performing hyperspectral time-domain diffuse optical spectroscopy to determine the optical properties of samples accurately using geometry specific models. To allow bulk parameter recovery from measured spectra, a set of libraries based on a numerical model of the domain being investigated is developed as opposed to the conventional approach of using an analytical semi-infinite slab approximation, which is known and shown to introduce boundary effects...
September 1, 2016: Biomedical Optics Express
Tyler Bowman, Magda El-Shenawee, Lucas K Campbell
This work presents experimental and analytical comparison of terahertz transmission and reflection imaging modes for assessing breast carcinoma in excised paraffin-embedded human breast tissue. Modeling for both transmission and reflection imaging is developed. The refractive index and absorption coefficient of the tissue samples are obtained. The reflection measurements taken at the system's fixed oblique angle of 30° are shown to be a hybridization of TE and TM modes. The models are validated with transmission spectroscopy at fixed points on fresh bovine muscle and fat tissues...
September 1, 2016: Biomedical Optics Express
Alexander Dvornikov, Enrico Gratton
Imaging depth in turbid media by two-photon fluorescence microscopy depends on the ability of the optical system to detect weak fluorescence signals. We have shown that use of a wide area detector in transmission geometry allows increasing imaging depth in turbid media due to efficient photon collection. Compared to the conventional epi-detection scheme used in most commercial microscopes, the transmission detector was found to be 2-3 orders of magnitude more sensitive when used for in depth imaging in scattering samples simulating brain optical properties...
September 1, 2016: Biomedical Optics Express
Martine Boccara, Yasmina Fedala, Catherine Venien Bryan, Marc Bailly-Bechet, Chris Bowler, Albert Claude Boccara
There is a huge abundance of viruses and membrane vesicles in seawater. We describe a new full-field, incoherently illuminated, shot-noise limited, common-path interferometric detection method that we couple with the analysis of Brownian motion to detect, quantify, and differentiate biotic nanoparticles. We validated the method with calibrated nanoparticles and homogeneous DNA or RNA viruses. The smallest virus size that we characterized with a suitable signal-to-noise ratio was around 30 nm in diameter. Analysis of Brownian motions revealed anisotropic trajectories for myoviruses...
September 1, 2016: Biomedical Optics Express
Tahereh Marvdashti, Lian Duan, Sumaira Z Aasi, Jean Y Tang, Audrey K Ellerbee Bowden
We report the first fully automated detection of basal cell carcinoma (BCC), the most commonly occurring type of skin cancer, in human skin using polarization-sensitive optical coherence tomography (PS-OCT). Our proposed automated procedure entails building a machine-learning based classifier by extracting image features from the two complementary image contrasts offered by PS-OCT, intensity and phase retardation (PR), and selecting a subset of features that yields a classifier with the highest accuracy. Our classifier achieved 95...
September 1, 2016: Biomedical Optics Express
Imke Nehrhoff, Diana Bocancea, Javier Vaquero, Juan José Vaquero, Jorge Ripoll, Manuel Desco, María Victoria Gómez-Gaviro
The ability to acquire high resolution 3D images of the heart enables to study heart diseases more in detail. In this work, the CUBIC (clear, unobstructed brain imaging cocktails and computational analysis) clearing protocol was optimized for thick mouse heart sections to enhance the penetration depth of the confocal microscope lasers into the tissue. In addition, the optimized CUBIC clearing of the heart enhances antibody penetration into the tissue by a factor of five. The present protocol enables deep 3D high-quality image acquisition in the heart allowing a much more accurate assessment of the cellular and structural changes that underlie heart diseases...
September 1, 2016: Biomedical Optics Express
Kan Lin, Wei Zheng, Chwee Ming Lim, Zhiwei Huang
We assess the clinical utility of a unique simultaneous fingerprint (FP) (i.e., 800-1800 cm(-1)) and high-wavenumber (HW) (i.e., 2800-3600 cm(-1)) fiber-optic Raman spectroscopy for in vivo diagnosis of laryngeal cancer at endoscopy. A total of 2124 high-quality in vivo FP/HW Raman spectra (normal = 1321; cancer = 581) were acquired from 101 tissue sites (normal = 71; cancer = 30) of 60 patients (normal = 44; cancer = 16) undergoing routine endoscopic examination. FP/HW Raman spectra differ significantly between normal and cancerous laryngeal tissue that could be attributed to changes of proteins, lipids, nucleic acids, and the bound water content in the larynx...
September 1, 2016: Biomedical Optics Express
Erwin J Alles, Sacha Noimark, Edward Zhang, Paul C Beard, Adrien E Desjardins
A miniature, directional fibre-optic acoustic source is presented that employs geometrical focussing to generate a nearly-collimated acoustic pencil beam. When paired with a fibre-optic acoustic detector, an all-optical ultrasound probe with an outer diameter of 2.5 mm is obtained that acquires a pulse-echo image line at each probe position without the need for image reconstruction. B-mode images can be acquired by translating the probe and concatenating the image lines, and artefacts resulting from probe positioning uncertainty are shown to be significantly lower than those observed for conventional synthetic aperture scanning of a non-directional acoustic source...
September 1, 2016: Biomedical Optics Express
Lingjie Kong, Justin P Little, Meng Cui
Functional imaging in behaving animals is essential to understanding brain function. However, artifacts resulting from animal motion, including locomotion, can severely corrupt functional measurements. To dampen tissue motion, we designed a new optical window with minimal optical aberrations. Using the newly developed high-speed continuous volumetric imaging system based on an optical phase-locked ultrasound lens, we quantified motion of the cerebral cortex and hippocampal surface during two-photon functional imaging in behaving mice...
September 1, 2016: Biomedical Optics Express
Michiko Nishiyama, Masako Sonobe, Kazuhiro Watanabe
In this paper, we present a pulse pressure waveform sensor that does not constrain a wearer's daily activity; the sensor uses hetero-core fiber optics. Hetero-core fiber sensors have been found to be sensitive to moderate bending. To detect minute pulse pressure changes from the radial artery at the wrist, we devised a fiber sensor arrangement using three-point bending supports. We analyzed and evaluated the measurement validity using wavelet transformation, which is well-suited for biological signal processing...
September 1, 2016: Biomedical Optics Express
Kyle Verdecchia, Mamadou Diop, Albert Lee, Laura B Morrison, Ting-Yim Lee, Keith St Lawrence
Diffuse correlation spectroscopy (DCS) is a promising technique for brain monitoring as it can provide a continuous signal that is directly related to cerebral blood flow (CBF); however, signal contamination from extracerebral tissue can cause flow underestimations. The goal of this study was to investigate whether a multi-layered (ML) model that accounts for light propagation through the different tissue layers could successfully separate scalp and brain flow when applied to DCS data acquired at multiple source-detector distances...
September 1, 2016: Biomedical Optics Express
Yulian A Menyaev, Kai A Carey, Dmitry A Nedosekin, Mustafa Sarimollaoglu, Ekaterina I Galanzha, Jason S Stumhofer, Vladimir P Zharov
In vivo photoacoustic flow cytometry (PAFC) has demonstrated potential for early diagnosis of deadly diseases through detection of rare circulating tumor cells, pathogens, and clots in nearly the entire blood volume. Before clinical application, this promising diagnostic platform requires verification and optimization using adequate preclinical models. We show here that this can be addressed by examination of large mouse blood vessels which are similar in size, depth and flow velocity to human vessels used in PAFC...
September 1, 2016: Biomedical Optics Express
Pierre Mangeol, Erwin J G Peterman
Most methods to observe three-dimensional processes in living samples are based on imaging a single plane that is sequentially scanned through the sample. Sequential scanning is inherently slow, which can make it difficult to capture objects moving quickly in three dimensions. Here we present a novel method, multiple point-of-view microscopy (MPoVM), that allows simultaneous capturing of the front and side views of a sample with high resolution. MPoVM can be implemented in most fluorescence microscopes, offering new opportunities in the study of dynamic biological processes in three dimensions...
September 1, 2016: Biomedical Optics Express
Gabriel Ramirez, Ashley R Proctor, Ki Won Jung, Tong Tong Wu, Songfeng Han, Russell R Adams, Jingxuan Ren, Daniel K Byun, Kelley S Madden, Edward B Brown, Thomas H Foster, Parisa Farzam, Turgut Durduran, Regine Choe
The non-invasive, in vivo measurement of microvascular blood flow has the potential to enhance breast cancer therapy monitoring. Here, longitudinal blood flow of 4T1 murine breast cancer (N=125) under chemotherapy was quantified with diffuse correlation spectroscopy based on layer models. Six different treatment regimens involving doxorubicin, cyclophosphamide, and paclitaxel at clinically relevant doses were investigated. Treatments with cyclophosphamide increased blood flow as early as 3 days after administration, whereas paclitaxel induced a transient blood flow decrease at 1 day after administration...
September 1, 2016: Biomedical Optics Express
Iliya Sigal, Margaret M Koletar, Dene Ringuette, Raanan Gad, Melanie Jeffrey, Peter L Carlen, Bojana Stefanovic, Ofer Levi
We report on a miniature label-free imaging system for monitoring brain blood flow and blood oxygenation changes in awake, freely behaving rats. The device, weighing 15 grams, enables imaging in a ∼ 2 × 2 mm field of view with 4.4 μm lateral resolution and 1 - 8 Hz temporal sampling rate. The imaging is performed through a chronically-implanted cranial window that remains optically clear between 2 to > 6 weeks after the craniotomy. This imaging method is well suited for longitudinal studies of chronic models of brain diseases and disorders...
September 1, 2016: Biomedical Optics Express
Chien-Shun Yan, Yao-Nan Wang
A multi-parameter optofluidic cytometer based on two low-cost commercial photovoltaic cells and an avalanche photodetector is proposed. The optofluidic cytometer is fabricated on a polydimethylsiloxane (PDMS) substrate and is capable of detecting side scattered (SSC), extinction (EXT) and fluorescence (FL) signals simultaneously using a free-space light transmission technique without the need for on-chip optical waveguides. The feasibility of the proposed device is demonstrated by detecting fluorescent-labeled polystyrene beads with sizes of 3 μm, 5 μm and 10 μm, respectively, and label-free beads with a size of 7...
September 1, 2016: Biomedical Optics Express
Chih-Ju Lin, Feng-Chieh Li, Yu-Yang Lee, Te-Yu Tseng, Wei-Liang Chen, Vladimir Hovhannisyan, Ning Kang, Nicholas G Horton, Shu-Jen Chiang, Chris Xu, Hsuan-Shu Lee, Chen-Yuan Dong
Hepatobiliary metabolism is one of the major functions of the liver. However, little is known of the relationship between the physiological location of the hepatocytes and their metabolic potential. By the combination of time-lapse multiphoton microscopy and first order kinetic constant image analysis, the hepatocellular metabolic rate of the model compound 6-carboxyfluorescein diacetate (6-CFDA) is quantified at the single cell level. We found that the mouse liver can be divided into three zones, each with distinct metabolic rate constants...
September 1, 2016: Biomedical Optics Express
Masahiro Yamanari, Satoru Tsuda, Taiki Kokubun, Yukihiro Shiga, Kazuko Omodaka, Naoko Aizawa, Yu Yokoyama, Noriko Himori, Shiho Kunimatsu-Sanuki, Kazuichi Maruyama, Hiroshi Kunikata, Toru Nakazawa
Estimation of polarimetric parameters has been a fundamental issue to assess biological tissues that have form birefringence or polarization scrambling in polarization-sensitive optical coherence tomography (PS-OCT). We present a mathematical framework to provide a maximum likelihood estimation of the target covariance matrix and its incoherent target decomposition to estimate a Jones matrix of a dominant scattering mechanism, called Cloude-Pottier decomposition, thereby deriving the phase retardation and the optic axis of the sample...
September 1, 2016: Biomedical Optics Express
Na Huang, Heng Guo, Weizhi Qi, Zhiwei Zhang, Jian Rong, Zhen Yuan, Wei Ge, Huabei Jiang, Lei Xi
The zebrafish, an ideal vertebrate for studying developmental biology and genetics, is increasingly being used to understand human diseases, due to its high similarity to the human genome and its optical transparency during embryonic stages. Once the zebrafish has fully developed, especially wild-type breeds, conventional optical imaging techniques have difficulty in imaging the internal organs and structures with sufficient resolution and penetration depth. Even with established mutant lines that remain transparent throughout their life cycle, it is still challenging for purely optical imaging modalities to visualize the organs of juvenile and adult zebrafish at a micro-scale spatial resolution...
September 1, 2016: Biomedical Optics Express
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