The Moscone Center
    San Francisco, California, United States
    28 January - 2 February 2017
    Print PageEmail Page

    Brain Presentations

    Neural Imaging, Sensing, Optogenetics, and Optical Manipulation
    (ordered by start date and time)


    Using stereotactic brain atlases for small rodents and nonhuman primates for optrode array customization.
    Paper 10052-3

    Author(s):  Ronnie Boutte, Northrop Grumman Mission Systems (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 1: Detection I
    Date and Time: Saturday, January 28, 2017, 9:40 AM

    As the optogenetic field expands its need to target, with high specificity, only grows more crucial. This work will show a method for customizing soda-lime glass optrode arrays so that fine structures within the brains of small rodents and nonhuman primates can be optically interrogated deep below the outer cortex. An 8X6 array is customized for optrode length (800um), optrode width (75um), optrode pitch (400um), backplane thickness (500um), and overall form factor 3.45mm x 2.65mm. The 800um long optrode is capable of stopping at the neocortical boundary of layer III and layer IV of nonhuman primate (Macaca Fascicularis).


    Deep brain single optical fiber fluorescence imaging
    Paper 10052-5

    Author(s):  Israel Delarosa, Univ. of Wisconsin-Milwaukee (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 2: Detection II
    Date and Time: Saturday, January 28, 2017, 10:50 AM

    A novel optoelectronic design is proposed, that uses only a relatively thin penetrating and rotating side-firing fiber to scan the brain tissue and collect data sets. The processed data sets are used to reconstruct images displaying the distribution of fluorescence molecules in a cylindrical volume surrounding the fiber and applied algorithms model light-tissue interaction in the brain. We expect to achieve a radial penetration depth of ~1.0mm around the optical axis of the fiber with axial resolution of ~100um or better, while each complete scan takes time in the range of several minutes.


    Micro-device combining electrophysiology and optical imaging for functional brian monitoring in freely moving animals
    Paper 10052-6

    Author(s):  Peng Miao, Johns Hopkins Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 2: Detection II
    Date and Time: Saturday, January 28, 2017, 11:10 AM

    Monitoring brain activities in awake and freely moving status is very important in physiological and pathological studies of brain functions. In this study, we developed a new standalone micro-device combining electrophysiology and optical imaging for monitoring the cerebral blood flow and neural activities with more feasibility for freely moving animals.


    Organic LEDs as biocompatible light sources for optogenetics
    Paper 10052-8

    Author(s):  Malte C. Gather, Univ. of St. Andrews (United Kingdom), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 3: Stimulation I
    Date and Time: Saturday, January 28, 2017, 1:50 PM

    Optogenetic stimulation will benefit from biocompatible light sources with spatially and temporally controlled illumination. Here, we show that organic light-emitting diodes (OLEDs) are highly attractive in this context, in particular due to their low toxicity, fast switching, high brightness, and ability to provide patterned illumination with very high spatial resolution. OLED microdisplays containing >100,000 individual top-emitting OLED pixels with µm dimensions are used to control cell behaviour and electrophysiology. We also demonstrate OLED mediated optogenetic control of Drosophila larvae and show that, maybe somewhat against common expectation, state-of-the-art pin OLEDs reliably achieve sufficient light intensities to stimulate neurons.


    Reconfigurable visible nanophotonic switch for optogenetic applications
    Paper 10052-12

    Author(s):  Aseema Mohanty, Columbia Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 4: Stimulation II
    Date and Time: Saturday, January 28, 2017, 3:50 PM

    High spatiotemporal resolution deep-brain optical excitation for optogenetics would enable activation of specific neural populations and in depth study of neural circuits. Active switching on a nanophotonic platform is necessary for eventually controlling highly-multiplexed reconfigurable optical circuits, enabling high-resolution optical stimulation in deep-brain regions. Here we use a silicon nitride waveguide platform to demonstrate the first active integrated optical switch for neural excitation at 473 nm, enabling control of multiple beams for deep-brain neural stimulation. We test the fully-packaged devices in-vivo and demonstrate single-cell optical activation of neural activity from different grating emitters.


    Measurement of light transmission and irradiance in brain tissue in vivo
    Paper 10052-14

    Author(s):  John J. Macklin, Howard Hughes Medical Institute (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 4: Stimulation II
    Date and Time: Saturday, January 28, 2017, 4:30 PM

    We describe methods to directly measure light transmission and irradiance profiles (axial and transverse) in mice. Light transmission is generally obtained from acute tissue sections, which differs from intact, live tissue. To quantify light transmission in multiple brain regions, measurements were made at 5 wavelengths (405 nm to 640 nm) for distances of 50 um to 4 mm from an embedded fiber optic source. These techniques and results can guide the design of optogenetics experiments and tools; test assumptions about light intensity in vivo; and more broadly can provide dosimetry for localized light-driven therapies targeting disease deep in tissue.


    3D Monte Carlo model with direct photon flux recording for optimal optogenetic light delivery
    Paper 10052-15

    Author(s):  Younghoon Shin, Gwangju Institute of Science and Technology (Korea, Republic of), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 4: Stimulation II
    Date and Time: Saturday, January 28, 2017, 4:50 PM

    We present a new mesh-based 3D Monte Carlo model that record the direct photon flux for optogenetic applications. Our method is aimed to maximize near-field recording efficiency by considering the proximity condition between a source and neural target. Unlike the conventional weight-loss approach, the photon trajectory is recorded in the volumetric grid planes and the photons under absorption is terminated without reduction of weight for efficiency. We investigated light delivery for optogenetic applications using various methods and demonstrated that our method can be applied to design optimal conditions with accurate estimates of intensity.


    Photovoltaic restoration of sight in rodents with retinal degeneration
    Paper 10052-16

    Author(s):  Daniel V. Palanker, Stanford Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 5: Stimulation III
    Date and Time: Sunday, January 29, 2017, 8:30 AM

    Photovoltaic retinal prosthesis is designed to restore sight in patients blinded by the loss of photoreceptors. Visual information is projected onto the retina by video goggles using pulsed NIR light. Subretinal photovoltaic pixels convert light into pulsed electric current, stimulating the nearby inner retinal neurons. This wireless design greatly reduces the surgical complexity, allows scaling the implants to thousands of electrodes, and multiple modules can be tiled under the retina to expand the visual field. Photovoltaic arrays with 70um pixels restored visual acuity up to a single pixel pitch, which is only two times lower than natural acuity in rats.


    Short infrared laser pulses block action potentials in neurons
    Paper 10052-17

    Author(s):  Alexandra J. Walsh, Air Force Research Lab. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 5: Stimulation III
    Date and Time: Sunday, January 29, 2017, 9:20 AM

    Rat hippocampal neurons were transfected with the Optopatch2 plasmid which contains a blue-light activated channel rhodopsin (CheRiff) and a fluorescent membrane voltage reporter, QuasAr2. This platform allows stimulation and recording of action potential activity. Reversible action potential block in neurons was observed following a short infrared laser pulse, with the block persisting for more than 1 s with exposures greater than 0.69 J/cm2. Action potential block was sustained for 30 s with repeated laser pulses. These results indicate that short infrared laser pulses can be used for reversible action potential block.


    Neural responses of rat cortical layers due to infrared neural stimulation
    Paper 10052-19

    Author(s):  John Logan Jenkins, Vanderbilt Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 6: Stimulation IV
    Date and Time: Sunday, January 29, 2017, 10:30 AM

    Infrared neural stimulation (INS) is a label-free method for eliciting neural activity with high spatial selectivity in mammalian models. While there has been an emphasis on INS research towards applications in the peripheral nervous system and the central nervous system, the biophysical mechanisms by which INS occurs remains unresolved. In this study, we present the neural responses of different cortical cell types due to exposure to pulsed infrared light (λ=1.875 µm, 200 µm fiber, 200 Hz) using electrophysiological and optical techniques, which may lead to a better understanding of the cell populations that are sensitive to INS.


    Spectral-temporal modulation of supercontinuum generation for optogenetics
    Paper 10052-20

    Author(s):  Yuan-Zhi Liu, Univ. of Illinois at Urbana-Champaign (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 6: Stimulation IV
    Date and Time: Sunday, January 29, 2017, 10:50 AM

    By combining optical and genetic methods, optogenetics has become a very important tool in neuroscience research for manipulating neuron activities. Photonic crystal fiber-based supercontinuum generation is proposed as a broadband coherent light source for two-photon optogenetic excitation and calcium imaging. Programmable pulse shaping is utilized to modulate the phases of partial wavelengths to tailor the temporal shape of the femtosecond pulse, which manipulates the absorption of optogenetic probes and provides a unique approach for controllable optogenetic excitation. Video-rate calcium imaging results suggest that spectral-temporal programmable supercontinuum pulses provides a powerful tool for neural network activity research.


    Analysis of components of compound action potentials in response to infrared laser light
    Paper 10052-21

    Author(s):  Junqi Zhuo, Case Western Reserve Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 6: Stimulation IV
    Date and Time: Sunday, January 29, 2017, 11:10 AM

    Many techniques, including infrared light, are being studied for modulating peripheral nerve activity. Analysis methods must determine if CAP (compound action potential) sub-components have been selectively enhanced or blocked. A numerical simulation explored the stability of several quantitative measures when CAP sub-components were shifted or blocked. Rectified area under the curve provided a more stable measure of change than other options (e.g., power). By selecting the lowest variance of the normalized area, the boundary between sub-components could be objectively defined. The analysis shows that slower components are blocked before faster components using IR in Aplysia californica nerves and shrew vagus.


    Multi-Characteristics Opsin enabled vision restoration
    Paper 10052-24

    Author(s):  Samarendra K. Mohanty, Nanoscope Technologies, LLC (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 8: Application
    Date and Time: Sunday, January 29, 2017, 1:40 PM

    Here, we demonstrate vision restoration using Multi-Characteristics Opsin (MCO) in animal models with photo-degenerated retina. MCO is reliably delivered to specific retinal cells via intravitreal injection of Adeno-Associated Virus, leading to significant improvement in visually guided behavior conducted using a radial-arm water maze. The number of error arms and time to reach platform significantly reduced after delivery of MCO. Biodistribution study using qPCR analysis showed negligible quantities of MCO-gene in different tissues of the treated mice. Safe virus-mediated MCO-delivery has potential for effective gene therapy of diverse retinal degenerations in patients.


    Infrared light causes short- and long-term modulation of phrenic nerve activity
    Paper 10052-25

    Author(s):  Gjinovefa Kola, Case Western Reserve Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 8: Application
    Date and Time: Sunday, January 29, 2017, 2:00 PM

    Infrared light has been shown to both excite and inhibit neural activity over the short term. We therefore hypothesized that it could modulate phrenic nerve activity (PNA). We found that IR could either excite or inhibit PNA, depending radiant exposure levels, and that it induced long-term changes similar to those evoked by serotonin or short hypoxic exposures. IR may therefore be a new modality for evoking neuroplasticity and neuromodulation of motor nerve activity.


    Safety and selectivity of infrared block for small-diameter axons
    Paper 10052-27

    Author(s):  Emilie H. Lothet, Case Western Reserve Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session 8: Application
    Date and Time: Sunday, January 29, 2017, 2:40 PM

    We demonstrated that infrared light is capable of selectively blocking action potentials with axonal sub-population resolution, preferentially affecting small-diameter, slower-conducting axons. Using unmyelinated Aplysia californica nerves, we found that infrared light could be applied for extended periods of time without causing functional damage to the nerve. We also demonstrated that selective block could be initiated in < 1 second. Long-lasting and fast selective control of smaller-diameter, slow-conducting axons could have significant therapeutic implications.


    Initial proof-of-concept of photoacoustic cell stimulation approach: preliminary in vitro study
    Paper 10052-22

    Author(s):  Jeeun Kang, Johns Hopkins Univ. (United States), et al.
    Conference 10052: Optogenetics and Optical Manipulation
    Session PSun: Posters-Sunday
    Date and Time: Sunday, January 29, 2017, 5:30 PM

    Localized, non-invasive cell stimulation method has been desired. Here we propose the initial proof-of-concept in vitro study of the photoacoustic cell stimulation approach, which is totally non-invasive and high-throughput solution broadening the way of cellular stimulation. The preliminary proof-of-concept in vitro study present that the primary neurons can indicate the significant membrane potential change by means of the photoacoustic stimulation, which is comparable to that of the potassium chloride-administrated control group. We envisage that the proposed approach can allow broad strategies for non-invasive cell stimulation by using the photoacoustic contrasts situated at inside or outside of the body.


    Effect of hindpaw electrical stimulation on capillary flow heterogeneity and oxygen delivery in rodents in vivo
    Paper 10051-1

    Author(s):  Yuandong Li, Univ. of Washington (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 1: OCT I
    Date and Time: Monday, January 30, 2017, 8:00 AM

    We report a novel use of optical coherence tomography (OCT) based angiography to visualize and quantify dynamic response of cerebral capillary flow pattern in mice upon hindpaw electrical stimulation through the measurement of the capillary transit-time heterogeneity (CTH) and capillary mean transit time (MTT). The OCT system was developed to have a central wavelength of 1310 nm, a spatial resolution of ~8 µm and a system dynamic range of ~105 dB at an imaging rate of 92 kHz. The mapping of dynamic cerebral microcirculations was enabled by optical microangiography protocol.


    Visible light spectral domain optical coherence microscopy system for ex vivo imaging
    Paper 10051-2

    Author(s):  Antonia Lichtenegger, Medizinische Univ. Wien (Austria), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 1: OCT I
    Date and Time: Monday, January 30, 2017, 8:30 AM

    A spectral domain optical coherence microscope (OCM) was developed. The system operates in the visible wavelength range of 465-690 nm. This extremely broad bandwidth enables an ultrahigh axial resolution of 1.4 μm (1.0 μm in tissue). Using a homemade spectrometer with a spectral resolution of 0.03 nm, a depth range of 2.4 mm in tissue was achieved. Cerebral tissues from non-pathological and Alzheimer’s disease affected brains were imaged. Based on our preliminary data, visible light OCM imaging has the potential to provide 3D spectroscopic contrast of endogenous as well as of established immunohistochemical markers used in state-of-the-art neuropathological practice.


    Assessing cortical and subcortical changes in a western diet mouse model using spectral / Fourier domain OCT
    Paper 10051-4

    Author(s):  Marcel T. Bernucci, Univ. of California, Davis (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 1: OCT I
    Date and Time: Monday, January 30, 2017, 9:10 AM

    The Western diet, causative in the development of atherosclerotic cardiovascular disease, has recently been associated with the development of diffuse white matter disease (WMD). To better understand the role of Western Diet in the development of WMD, intensity and Doppler flow OCT images, obtained using a 1300 nm SD- spectral / Fourier domain OCT system, were used to observe the structural and functional alterations in the cortex and corpus callosum of Western Diet and control diet mouse models. We show evidence that collateral tortuosity was significantly higher in the Western diet animal group, and that the corpus callosum is thinner in Western diet mice.


    Imaging mouse cerebellum using serial optical coherence scanner
    Paper 10051-5

    Author(s):  Chao J. Liu, Univ. of Minnesota, Twin Cities (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 1: OCT I
    Date and Time: Monday, January 30, 2017, 9:30 AM

    We present visualization of the cerebellum and adjacent brainstem of mouse by the serial optical coherence scanner (SOCS), which consists of a polarization sensitive optical coherence tomography and a vibratome with associated controls for ex-vivo serial imaging. The cerebellar cortical layers and white matter are distinguished by using intrinsic optical contrasts. Large-scale anatomy and the nerve fiber pathways are constructed at 10 μm lateral resolution with a scan lens. Incorporating a water-immersion microscope objective resulted in higher resolution (4 μm) images for selected slices. SOCS has potential to study pathological changes and monitor the effects of treatment in cerebellar diseases.


    In-vivo imaging of the morphology and blood perfusion of brain tumours in rats with UHR-OCT
    Paper 10051-6

    Author(s):  Kostadinka Bizheva, Univ. of Waterloo (Canada), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 1: OCT I
    Date and Time: Monday, January 30, 2017, 9:50 AM

    Brain tumors are characterized with morphological changes at cellular level such as enlarged, non-spherical nuclei and are highly vascularized. Research-grade optical coherence tomography (OCT) systems operating at ~800 nm and ~1060 nm with axial resolution of 0.95 µm and 3.5 µm in biological tissue respectively, were used to image in vivo and ex vivo the structure of brain tumours in rats. The morphological OCT images were correlated with H&E histology of the tumour. By utilizing different data acquisition protocols for Doppelr OCT and optical microangiography (OMAG) during the in vivo imaging session, 3D images of the tumour vasculature were generated.


    Optical changes in cortical tissue during seizure activity using optical coherence tomography
    Paper 10051-8

    Author(s):  Danielle Ornelas, Univ. of California, Riverside (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 2: OCT II
    Date and Time: Monday, January 30, 2017, 11:00 AM

    Optical coherence tomography (OCT) is a label-free, high resolution, and minimally invasive imaging technique that can produce depth-resolved cross-sectional and 3D images. In this study, OCT was used to detect non-vascular depth-dependent optical changes in cortical tissue during 4-aminopyridine (4-AP) induced seizure onset. The results of this study reveal a significant depth-dependent decrease in attenuation coefficient of nonvascular cortical tissue during seizure onset and progression both ex vivo and in vivo, with significant temporal correlation electrophysiology activity


    Closed-loop optogenetic control of cortical hemodynamics
    Paper 10051-9

    Author(s):  Rex Chin-Hao Chen, Univ. of Wisconsin-Milwaukee (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 2: OCT II
    Date and Time: Monday, January 30, 2017, 11:20 AM

    The combination of optogenetics and optical imaging modalities has become a popular tool for investigation of neurovascular coupling. Developing a closed-loop hemodynamic control system capable of dynamically following various blood flow patterns could be beneficial to the causal investigation of neurovascular coupling. To develop this closed-loop control system for the cortical vasculature of Thy1-Channelrhodopsin-2 mice, we integrated optogenetics and optical coherence tomography with a proportional-derivative compensator. This system is capable of monitoring the cross-sectional velocity profile of a vessel in real-time and simultaneously adjusting the stimulation parameters of a pulsed laser based on blood flow dynamic measurements.


    Spatial and temporal cerebral hemodynamic response after regional optogenetic stimulation in mice
    Paper 10051-10

    Author(s):  Farid Atry, Univ. of Wisconsin-Milwaukee (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 2: OCT II
    Date and Time: Monday, January 30, 2017, 11:40 AM

    To conduct spatially and temporally cell type–specific neurovascular coupling studies, we have developed a platform utilizing optogenetics and optical coherence tomography. This platform can directly modulate neural activity in the cerebral cortex of Thy1-Channelrhodopsin-2 (ChR2) mice, while monitoring the cross-section of blood vessels. We have used this platform to study hemodynamics following local optogenetic stimulation with varying irradiance, power, and stimulation spot size. For spot diameters between 0.267mm and 0.8mm, the blood flow and velocity responses were closely related to the stimulation optical power. The maximum blood flow response happened when the stimulation site co-locates with the vascular territory.


    Imaging human brain cytoarchitecture with quantitative optical coherence tomography
    Paper 10051-11

    Author(s):  David A. Boas, Athinoula A. Martinos Ctr. for Biomedical Imaging (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 3: Whole Brain Imaging
    Date and Time: Monday, January 30, 2017, 1:30 PM

    No current imaging technology allows us to directly and without significant distortion visualize the microscopic and defining anatomical features of the human brain. Ex vivo histological techniques can yield exquisite planar images, but the cutting, mounting and staining that are required components of this type of imaging induce distortions that are different for each slice, introducing cross-slice differences that prohibit true 3D analysis. We are overcoming this issue by utilizing Optical Coherence Tomography (OCT) with the goal to image whole human brain cytoarchitectural and laminar properties with potentially 3.5 µm resolution in block-face without the need for exogenous staining.


    High-throughput dual-color precision imaging for brain-wide mapping of the connectome with cytoarchitectonic landmarks at the cellular level
    Paper 10051-12

    Author(s):  Qingming Luo, Huazhong Univ. of Science and Technology (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 3: Whole Brain Imaging
    Date and Time: Monday, January 30, 2017, 2:00 PM

    Deciphering the fine morphology and precise locations of neural structures are crucial to enhance our understanding of brain function. Here, we present a high-throughput imaging method that can automatically obtain brain-wide neural circuits and their cytoarchitecture reference at single-neuron resolution. The method consists of employing wide-field large-volume tomography to acquire three-dimensional images of thick tissue and implementing real-time soma counterstaining to obtain cytoarchitectonic landmarks during imaging process. Using our method, mouse brain imaging datasets of multiple type-specific neurons and circuits were successfully acquired, demonstrating the versatility. We believe our method could contribute to cell type, projectome and connectome studies.


    A large field of view, high resolution Bessel beam two-photon light sheet microscope for large-scale 3D brain imaging
    Paper 10051-13

    Author(s):  Cleophace Akitegetse, Univ. Laval (Canada), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 3: Whole Brain Imaging
    Date and Time: Monday, January 30, 2017, 2:30 PM

    Recent advances in light-sheet microscopy have made possible high-throughput large-scale imaging. Generating thin and large light-sheets remains, however, challenging. We present a novel large field of view light-sheet microscope with a high axial resolution. A light-sheet is obtained by scanning a Bessel beam, generated using an axicon, and we are able to achieve a large field of view without compromising the axial resolution. The combination of our light-sheet technology with optical clearing promises to transform our ability to understand the neuro-circuitry of the brain and thus significantly advance understanding of neurological and psychiatric diseases which involve remodelling of brain connections.


    Sub-micron opto-chemical probes for studying living neurons
    Paper 10051-15

    Author(s):  Mani Hossein-Zadeh, Intelligent Optical Systems, Inc. (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 4: Novel Biomarker or Model
    Date and Time: Monday, January 30, 2017, 3:40 PM

    We have fabricated sub-micron opto-chemical probes with conformal functional coatings and demonstrated their application in monitoring of neurons. The geometry of the functionalized region on the probe combined with high sensitivity imaging enables simultaneous optical monitoring of spatially adjacent but distinct compartments as well as differential measurement of the target parameter referenced to a stable bath. As proof of concept we impaled cultured neurons (cortical neuronal cultures) and acute hippocampal slices with these probes to measure calcium, oxygen and pH. We have also demonstrated multifunctional probes capable of measuring up to three parameters in the extracellular space in brain slices.


    A novel reactive embedding resin for mapping of neural circuits
    Paper 10051-16

    Author(s):  Shaoqun Zeng, Britton Chance Ctr. for Biomedical Photonics, Huazhong Univ. of Science and Technology (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 4: Novel Biomarker or Model
    Date and Time: Monday, January 30, 2017, 4:00 PM

    Tissue embedding a critical technology image quality in biological tissue imaging. The embedding resin largely affects the embedding effect in embedding process. Here, we developed a novel reactive plastic embedding resin with the biological tissue via the reaction of epoxy group and amino group, compatibility biological tissue and can be good to preserve the fluorescence intensity of endogenous fluorescent protein and dyes in biological tissue. This resin can potentially be applied in serial sectioning large sample for fluorescence microscopy imaging or electron microscopy imaging.


    Hypertension and stroke: the changes in permeability of blood-brain barrier in rats
    Paper 10051-17

    Author(s):  Oxana V. Semyachkina-Glushkovskaya, Saratov State Univ. (Russian Federation), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 4: Novel Biomarker or Model
    Date and Time: Monday, January 30, 2017, 4:20 PM

    It is well established that hypertension (HP) is main risk factor for stroke but mechanisms underlying this problem remain not clear. Here we tested our hypnotize that high pressure exhausts adaptive capacity of cerebral endothelium and blood-brain barrier (BBB) to stress, which can provokes stroke due to the increase in permeability of BBB and cytotoxic brain oedema. Our results showed that HP is accompanied by cerebral ischemia but without any changes in BBB permeability. The acute and strong stress causes the increase BBB permeability, which is associated with stroke in most hypertensive rats.


    Wearable ear EEG for brain interfacing and monitoring
    Paper 10051-40

    Author(s):  Amanda S. Danko, USAA (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Brain-computer interfaces measuring electrical activity via electroencephalogram (EEG) have evolved beyond clinical applications to become wireless consumer products. Marketed for meditation and neurotherapy, these devices are currently too obtrusive to be a ubiquitous wearable. In this work, an ear-EEG device is created with a novel system for artifact removal and signal interpretation. Compact, cost-effective, and discreet, the device is compared to existing consumer electronics in this space for signal quality, comfort, and usability. A custom mobile app is implemented to process raw EEG from each device and display interpreted data to the user.


    Online monitoring of tissue response to plasma coated rigid neural implants using fiber-based optical coherence tomography
    Paper 10051-41

    Author(s):  Ian Dryg, Univ. of Washington (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Microfabricated neuroprosthetic devices have made possible important observations on neuron activity; however, long-term high fidelity recording performance has yet to be realized. Tissue-device interactions appear to be a primary source of lost recording performance, but are predominantly studied by post-hoc histology. Monitoring the developing tissue response could inform improvements in electrode design. Here, for the first time, we use fiber-based Optical Coherence Tomography (OCT) to achieve real-time, in-vivo monitoring of the tissue response surrounding chronically implanted rigid neural devices. The employed implants are coated with biocompatible and anti-inflammatory plasma nanofilms. We compare OCT results to traditional histology qualitatively and quantitatively.


    Functional near infrared spectroscopy for awake monkey to accelerate neurorehabilitation study
    Paper 10051-42

    Author(s):  Hiroshi Kawaguchi, National Institute of Advanced Industrial Science and Technology (Japan), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Functional near infrared spectroscopy (fNIRS) was applied to the measurement of the awake monkey to accelerate neurorehabilitation studies. The computer simulation of the light propagation in monkey head was performed on sophisticated anatomical models based on magnetic resonance images. We found that 15 mm is the optimal interval for the fNIRS measurement of monkey motor cortex. In the preliminary fNIRS measurement, the custom-made probe holder was attached over bilateral primary motor cortices of a monkey. Increases and decreases in oxy- and deoxy-hemoglobin were observed in the localized area in the hemisphere contralateral to the moved hand.


    Method for leveling the signal-to-noise ratio in multichannel functional near-infrared spectroscopy
    Paper 10051-43

    Author(s):  Toru Yamada, National Institute of Advanced Industrial Science and Technology (Japan), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Difference in the signal-to-noise ratio (SNR) of multichannel functional near-infrared spectroscopy (fNIRS) is severe problem to quantitatively identify functional activation area. To level SNR at channels in fNIRS, a novel system equipped with optical attenuator for each light source and detector was developed. By modulating the attenuators based on a systematic procedure that mathematically formulated, light intensities at the detectors can be equalized. The apparent detector noises, thus the SNR at all the channels, are leveled through this procedure. The method was examined by using the optical phantom with partly hair-covered surface.


    A pH-sensitive red fluorescent protein compatible with hydrophobic resin embedding
    Paper 10051-44

    Author(s):  Wenyan Guo, Wuhan National Lab. for Optoelectronics (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    pH sensitive fluorescent proteins enabling chemical reactivation in resin are useful tools for fluorescence microimaging. EYFP or EGFP improved from GFP in jellyfish are good for such applications. For simultaneous two-color imaging, a suitable red fluorescent protein is of urgent need. Here a pH sensitive red fluorescent protein, pHuji, is selected and verified to be compatible with hydrophobic resin embedding and thus may be promising for dual-colour chemical reactivation imaging in conjuntion with EGFP or EYFP.


    Chemical sectioning: high throughput imaging brain networks ex vivo at synaptic resolution
    Paper 10051-45

    Author(s):  Shaoqun Zeng, Wuhan National Lab. for Optoelectronics (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM


    Optical fiber based methods for deep brain calcium signal measurements in behaving mice
    Paper 10051-46

    Author(s):  Ling Fu, Huazhong Univ. of Science and Technology (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM


    NeuroGPS-Tree: Automatic reconstruction of large-scale neuronal populations with dense neurites
    Paper 10051-47

    Author(s):  Hang Zhou, Wuhan National Lab. for Optoelectronics, Huazhong Univ. of Science and Technology (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM


    A portable, multi-channel fNIRS system for prefrontal cortex: study on neurofeedback and imagery tasks
    Paper 10051-48

    Author(s):  Seung-ho Paik, Korea Univ. (Korea, Republic of), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    fNIRS is a neuroimaging technique which uses a near-infrared light source (in the range of 700-1000 nm) and allows for the detection of hemodynamic changes. We developed a portable, multidistance prefrontal fNIRS system which has 12 light sources and 15 detectors for a total of 108 channels, with a sampling rate of 5 Hz. Previously, we performed left and right arm motor imagery tasks that produced statistically significant changes of oxyhemoglobin concentration in the prefrontal cortex areas. In this study, we measured prefrontal and motor cortex oxyhemoglobin concentrations simultaneously during motor imagery task. Furthermore we developed simple device for BMI (Brain Machine Interface) and tested it with neurofeedback training.


    High-throughput reconstruction of single neuronal morphology at brain-wide scale
    Paper 10051-49

    Author(s):  Shiwei Li, Wuhan National Lab. for Optoelectronics, Huazhong Univ. of Science and Technology (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Reconstructing the single neuronal morphology is the key to acquire the neuron circuit structure. High-resolution and brain-wide imaging of single neuron has generated complex and huge dataset. From these dataset, reconstruct the neuron morphology remain challengeable. Here, we propose a self-learning algorithm, Smart Tracer, which provides the effective reconstruction in complex environment. We developed a platform of mess data reading and management which breaks the bottleneck in processing whole-brain dataset. We also integrated the self-learning algorithm into this platform, named Smart Brain-wide Tracer. By using Smart Brain-wide Tracer, we achieve the high-throughput reconstruction of single neuronal morphology at brain-wide scale.


    Investigation soluble epoxide hydrolase inhibitor effects on cerebrovascular functions of focal ischemic stroke rats by novel dual-wavelength optical imaging
    Paper 10051-51

    Author(s):  Han-Chi Pan, National Health Research Institutes (Taiwan), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    The novel dual-wavelength optical imaging system combines laser speckle contrast imaging and intrinsic optical signals imaging for simultaneous recording of cerebral blood flow (CBF) and hemoglobin oxygenation through a cranial optical window with high spatial resolution, fine temporal resolution and low costs of advantages. The effects of soluble epoxide hydrolase inhibitor, AUDA, on focal photothrombotic ischemia (PTI) of rats are also examined by using the optical imaging system for measuring the dynamics of CBF and hemoglobin oxygenation. The results demonstrate that AUDA not only significantly restored the CBF and hemoglobin oxygen-saturation, but also reduced the PTI stroke-induced brain damages.


    Polarization sensitive micro optical coherence tomography for cerebral cortex imaging
    Paper 10051-52

    Author(s):  Nanshuo Wang, Nanyang Technological Univ. (Singapore), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM


    Time-frequency functional brain connectivity during noxious stimulation by near infrared spectroscopy
    Paper 10051-53

    Author(s):  Raul Fernandez Rojas, Univ. of Canberra (Australia), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    In this study, we use multichannel NIRS to assess the frequency-specific features of interhemispheric connectivity of somatosensory regions of the cortex after noxious stimulation. We recorded the hemodynamic activity of eleven subjects during an acupuncture procedure. To clarify the coherence of functional connectivity, we calculated the wavelet coherence between corresponding channel pairs on both somatosensory regions. The results showed that functional connectivity between homologous channels in both hemispheres presented high coherence around three frequency ranges. Functional connectivity was significantly stronger during stimulation task and weaker during resting time. These findings suggest that synchronization of cortical activity in response to stimulation reflects interhemispheric connectivity in the somatosensory region. This study contributes to the research field to investigate interhemispheric connectivity using NIRS.


    Resonance Raman spectroscopy of human brain metastasis of lung cancer analyzed by blind source separation
    Paper 10051-54

    Author(s):  C.-H. Liu, City College of New York (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Resonance Raman (RR) spectroscopy offers a novel optical biopsy method in cancer discrimination by enhancement in Raman scattering. The RR spectra of human brain tissues were studied by a selected wavelength at 532 nm to explore the potential applications in human brain metastasis of lung cancer detection. The diagnostic significance was investigated by blind source separation (e.g. Principal Component Analysis). A linear discriminant analysis (LDA) classifier is used to evaluate the sensitivity and specificity. This research demonstrates that the Resonance Raman Spectroscopy is effective to detect spectral changes of tissues due to the development of brain metastasis of lung cancer.


    Deception detection by hybrid-pair wireless fNIRS system
    Paper 10051-55

    Author(s):  Di Hong, The Univ. of International Relations (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session PMon: Posters-Monday
    Date and Time: Monday, January 30, 2017, 5:30 PM

    Normal fNIRS setting up was limited by superficial physiological noises when applied into the lie detection. We designed a hybrid-pair wireless fNIRS system to improve the detection. The system takes advantages of short-pair channel to suppress the effect of physiological noises, and wireless module to improve the comfortableness of wearing it. We applied the system into a modified Guilty Knowledge Test. The experiment demonstrated that normal metrics might hint different energy consume during lying, while the regional oxygen saturation rSO_2, specific in the system, is sensitive to indicate a lying.


    Rehabilitation-triggered cortical plasticity after stroke: in vivo imaging at multiple scales
    Paper 10051-20

    Author(s):  Francesco S. Pavone, Lab. Europeo di Spettroscopie Non-Lineari, Univ. degli Studi di Firenze (Italy), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 5: Fluorescence Imaging I
    Date and Time: Tuesday, January 31, 2017, 8:00 AM


    Through-skull vasculature assessment using fluorescence brain imaging on murine models at around 800 nm
    Paper 10051-21

    Author(s):  Hanh N. D. Le, Johns Hopkins Univ. (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 5: Fluorescence Imaging I
    Date and Time: Tuesday, January 31, 2017, 8:30 AM

    Current effort using fluorescence-based technology has shown success in brain imaging, however, it requires invasive sample preparations such as craniotomy, cranial windows or skull-thinning procedures. Here we propose a near-infrared imaging setup operating around 800 nm for non-invasive brain imaging on live murine models. The imagery utilizes the inherent photoluminescence of a common, non-toxic indocyanine green dye for the vasculature monitoring delivered through peripheral veins. The system is calibrated with different excitation power levels for the enhancement of scattering observation and obtains resolution of 15.63 µm and an average local SNR of 25 dB.


    Simultaneous two-photon imaging of cerebral oxygenation and capillary blood flow in atherosclerotic mice
    Paper 10051-23

    Author(s):  Xuecong Lu, Ecole Polytechnique de Montréal (Canada), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 5: Fluorescence Imaging I
    Date and Time: Tuesday, January 31, 2017, 9:10 AM

    Gradual changes in brain microvasculature and cerebral capillary blood flow occurring with atherosclerosis may significantly contribute to cognition decline due to their role in brain tissue oxygenation. This study aimed to investigate vascular and concomitant changes in brain tissue PO2 with atherosclerosis. Experiments in young healthy C57B1/6 mice (n=6, control) and atherosclerotic mice (n=6, ATX) were performed with imaging at the left sensory-motor cortex at resting state under urethane (1.5g/kg) anesthesia using two-photon fluorescence microscopy. The results showed that PO2 around capillaries increased with atherosclerosis and correlated with red blood cell (RBC) flux in capillaries.


    An optical assessment of the effects of glioma growth on resting state networks in mice
    Paper 10051-24

    Author(s):  Inema E. Orukari, Washington Univ. in St Louis (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 5: Fluorescence Imaging I
    Date and Time: Tuesday, January 31, 2017, 9:30 AM

    Gliomas cause significant changes to normal brain function that lead to cognitive deficits. Disruptions in resting state networks (RSNs) are thought to underlie these changes. In this study, we evaluated the effects of tumor growth on RSNs in a glioma mouse model. Glioma cells were implanted into the cortex of adult mice. Disruptions in RSNs were evaluated weekly with functional connectivity optical intrinsic signal imaging (fcOIS). Deficits in RSNs initiated near the lesion, and over a period of several weeks, extend more globally. Thus, we have shown fcOIS is capable of detecting alterations in mouse RSNs due to glioma growth.


    Two-photon microscopy measurement of cerebral metabolic rate of oxygen using periarteriolar oxygen concentration gradients
    Paper 10051-25

    Author(s):  Sava Sakadžić, Athinoula A. Martinos Ctr. for Biomedical Imaging (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 5: Fluorescence Imaging I
    Date and Time: Tuesday, January 31, 2017, 9:50 AM

    We present a method of estimating CMRO2 that utilizes two-photon microscopy imaging of cortical tissue PO2. This method depends on a single imaging parameter (e.g., tissue PO2 around cortical penetrating arterioles), making it significantly less complex and potentially more accurate than existing CMRO2 measuring methods that rely on multimodal imaging of blood oxygenation and blood flow. In addition, the spatial resolution of this method is ~200 μm and it can be easily combined with other optical microscopy tools for preclinical studies in animals, providing novel approaches to address critical questions related to cortical pathological conditions.


    Measurement of cortical functional activation in awake mice using two-photon microscopy and a new PO2-sensitive probe
    Paper 10051-27

    Author(s):  Ikbal Sencan, Athinoula A. Martinos Ctr. for Biomedical Imaging (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 6: Fluorescence Imaging II
    Date and Time: Tuesday, January 31, 2017, 11:00 AM

    Measurements of changes in the cortical microvascular PO2 and blood flow in response to whisker stimulation were conducted in awake mice. Two-photon microscopy of PO2 was performed using a new oxygen-sensitive antenna-free phosphorescent probe with significantly improved performance. The amplitudes and shapes of the PO2 changes were mapped as a function of the vessel type and the distance from the activation center. Our results will lead to improved understanding of cerebral physiology and more quantitative interpretation of fMRI signals.


    Exploring infrared neural stimulation with multimodal nonlinear imaging
    Paper 10051-29

    Author(s):  Wilson R. Adams, Vanderbilt Univ. (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 6: Fluorescence Imaging II
    Date and Time: Tuesday, January 31, 2017, 11:40 AM

    Recent advances in nonlinear multimodal imaging have enabled real time visualization of biochemical dynamics in live cellular systems, presenting new avenues in neuroscience research. Here, we demonstrate the ability of our novel microscope platform to combine CARS, SRS, two-photon, second harmonic and thermal imaging into a single imaging system to study the biophysical dynamics of neural activity in thalamocortical brain slices during pulsed-IR neural stimulation. Pairing results of label-free nonlinear imaging with methods previously detailed in literature, we begin to attribute underlying biophysical mechanisms may be giving rise to INS phenomena.


    Photoacoustic microscopy of cerebral hemodynamic and metabolic responses to anesthetics
    Paper 10051-30

    Author(s):  Rui Cao, Univ. of Virginia (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 7: Photoacoustic Imaging
    Date and Time: Tuesday, January 31, 2017, 1:30 PM

    General anesthetics are known to have profound effects on cerebral hemodynamics and neuronal activities. However, it remains a challenge to directly assess anesthetics-induced hemodynamic and oxygen-metabolic changes from the true baseline under wakefulness at the microscopic level, due to the lack of an enabling technology for high-resolution imaging of the awake rodent brain. To address this challenge, we have developed first-of-a-kind head-restrained photoacoustic microscopy. Side-by-side comparison of the awake and anesthetized mouse brains revealed multifaceted cerebral responses to isoflurane—including the diameter-dependent arterial dilation, elevated cerebral blood flow, reduced oxygen extraction fraction, and declined cerebral metabolic rate of oxygen.


    Real-time reperfusion imaging for cerebral ischemia in rats using the multi-wavelength handheld photoacoustic system
    Paper 10051-31

    Author(s):  Yu-Hang Liu, National Univ. of Singapore (Singapore), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 7: Photoacoustic Imaging
    Date and Time: Tuesday, January 31, 2017, 1:50 PM

    In this study, based on the multi-wavelength laser and 18.5 MHz array-based ultrasound transducer, a real-time handheld photoacoustic (PA) system was developed to evaluate cerebrovascular functions including cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) pre- and post-stroke. Photothrombotic ischemia (PTI) and middle cerebral artery occlusion (MCAo) rat models were employed for evaluating the difference between local and global ischemia in reperfusion mechanism. Results demonstrate that stroke symptoms like hypoxia can be observed in both PTI and MCAo models post-stroke. Overall, the real-time handheld PA system holds great potential in disease models involving impairments in cerebrovascular functions.


    Photoacoustic imaging of biopotentials: a feasibility study
    Paper 10051-32

    Author(s):  Nashaat S. Rasheed, George Mason Univ. (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 7: Photoacoustic Imaging
    Date and Time: Tuesday, January 31, 2017, 2:10 PM

    We investigated the feasibility of photoacoustically visualizing biopotentials in rat pheochromocytoma (PC12) cells tagged with voltage-sensitive dye, RH795. A change in the intramembrane potential was induced in PC12 cells by adding tetraphenylborate (TPB). The absorption spectra of RH795 as a function of 100 µM TPB were recorded using a custom-made spectrophotometer. TPB-induced electrical fields resulted in a wavelength shift and an increase in the absorption magnitude of RH795. Photoacoustic measurements of TPB-induced change in membrane voltage were recorded at 700 nm excitation wavelength. Photoacoustic-signal amplitude increased monotonically with time after the addition of TPB, which was consistent with the spectrophotometer measurements.


    Mapping cell-specific functional connections in the mouse brain using ChR2-evoked hemodynamic signals
    Paper 10051-33

    Author(s):  Adam Q. Bauer, Washington Univ. School of Medicine in St. Louis (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 8: Intrinsic Signal Imaging
    Date and Time: Tuesday, January 31, 2017, 2:30 PM

    Evoked and spontaneous hemodynamic fluctuations reflect ensemble activity from several populations of neurons making it difficult to map subunits of a functional network. To add greater specificity to hemoglobin assays, we integrated optical intrinsic signal imaging in awake mice with the cell-specificity of optogenetics to create an Opto-OIS mapping tool. Optogenetically-defined maps exhibit higher spatial specificity than those determined using spontaneous hemodynamic fluctuations and closely recapitulated connectivity information contained in the Allen Mouse Brain Connectivity database. Opto-OIS mapping could be a powerful tool for understanding cellular and molecular contributions to network dynamics and processing in the awake, behaving mouse brain.


    Wide area mapping of resting state functional connectivity at microvascular resolution with multi-contrast optical imaging
    Paper 10051-34

    Author(s):  Janaka Senarathna, Johns Hopkins Univ. (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 8: Intrinsic Signal Imaging
    Date and Time: Tuesday, January 31, 2017, 2:50 PM

    Different brain regions exhibit complex information processing even at rest. Therefore, assessing temporal correlations between regions permits task-free visualization of their ‘resting state connectivity’. We built a customized system that combines laser speckle contrast imaging, intrinsic optical signal imaging and fluorescence imaging to generate multi-contrast resting state connectivity maps at a spatial resolution of 10 μm. Moreover, concurrent mapping of CBF and HbT-based temporal correlations enabled in vivo mapping of how resting brain regions were linked in terms of their hemodynamics. Overall, we demonstrated the feasibility of wide area mapping of resting state connectivity at microvascular resolution.


    Development of a multi exposure speckle imaging for mice brain imaging
    Paper 10051-35

    Author(s):  Haleh Soleimanzad, Univ. Paris-Sud (France), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 8: Intrinsic Signal Imaging
    Date and Time: Tuesday, January 31, 2017, 3:10 PM

    A multi exposure speckle imaging system has been developed and characterized for wide field blood flow imaging of the mice cortex. We report on the choice and validation of the system components including coherent light source, fast CMOS camera and acousto-optic modulator. We have characterized its performances using microfluidic phantoms composed of channels with diameters ranging from 10 to 200 microns where blood mimicking fluids speed is set between 1mm/s and 1cm/s. The first in vivo imaging attempts in the mice brain will be presented.


    Depth monitoring of cerebral hemodynamic changes using Monte Carlo-based probabilistic photon paths
    Paper 10051-36

    Author(s):  Zephaniah Phillips, Korea Univ. (Korea, Republic of), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 9: NIR Imaging
    Date and Time: Tuesday, January 31, 2017, 4:00 PM

    Accurate and efficient reconstruction of hemodynamic changes is an important step towards the implementation of NIRS as an enhanced clinical tool for understanding oxygenation changes at various depths within the brain. Depth information could provide insight on how oxygen transported to the tissue. For this work, we ran Monte Carlo simulations to derive probabilistic photon paths at various source-detector separations and weighted the hemodynamic changes according to these probabilities for use in depth reconstruction.


    Improved accuracy of brain oxygen metabolism measurements using multi-distance diffuse correlation spectroscopy and near infrared spectroscopy together with a Monte Carlo light transport model
    Paper 10051-38

    Author(s):  Stefan A. Carp, Athinoula A. Martinos Ctr. for Biomedical Imaging, Massachusetts Institute of Technology (United States), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 9: NIR Imaging
    Date and Time: Tuesday, January 31, 2017, 4:40 PM

    Diffuse correlation spectroscopy (DCS) is being employed alongside near-infrared spectroscopy (NIRS) measurements to track the cerebral oxygen metabolic rate (CMRO2). However, both techniques employ diffusely reflected light that has traveled mostly through extracerebral tissues. The mismatch between the depth sensitivity profiles of these two methods can lead to erroneous conclusions with respect to the amount and perhaps even the direction of change in CMRO2. In this paper we employ Monte Carlo simulations based on a realistic head geometry as a light transport model and quantify the improvements offered vs. processing the measurements with a semi-infinite diffusion model.


    Correlation between VEP and hemodynamics in visual cortex
    Paper 10051-39

    Author(s):  Xin Zhang, Institute of Automation (China), et al.
    Conference 10051: Neural Imaging and Sensing
    Session 9: NIR Imaging
    Date and Time: Tuesday, January 31, 2017, 5:00 PM


    Important Dates

    Abstracts Due
    17 July 2017

    Author Notification
    25 September 2017

    Manuscripts Due
    See Individual Conferences


    Sign up for event e-alerts

     Subscribe


    Journal of Biomedical Optics

    Journal of Biomedical OpticsPublishes peer-reviewed papers that utilize modern optical technology for improved health care and biomedical research.