Dynamic optical contrast imaging (DOCI): system theory for rapid, wide-field, multispectral optical imaging using fluorescence lifetime contrast mechanism

The microcirculation is a complex system, and the visualization of microcirculation has great significance in improving our understanding of pathophysiological processes in various disease conditions, in both clinical and fundamental studies. A range of techniques are available or emerging for investigating different aspect of the microcirculation in animals and humans. This paper reviews the recent developments in the field of high-resolution and high-sensitive optical imaging of microcirculatory tissue beds, emphasizing technologies that utilize the endogenous contrast mechanism. Optical imaging techniques such as intravital microscopy, Capillaroscopy, laser Doppler perfusion imaging, laser speckle perfusion imaging, polarization spectroscopy, photo-acoustic tomography, and various implementations of optical coherence tomography based on Doppler and speckle contrast imaging are presented together with their prospectives and challenges.

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A Large Lateral Craniotomy Procedure for Mesoscale Wide-field Optical Imaging of Brain Activity

Journal of Visualized Experiments ◽

10.3791/52642 ◽

2017 ◽

Cited By ~ 7

Author(s):

Michael Kyweriga ◽

Jianjun Sun ◽

Sunny Wang ◽

Richard Kline ◽

Majid H. Mohajerani

Keyword(s):

Optical Imaging ◽

Brain Activity ◽

Wide Field

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X-ray imaging with ultra-small-angle X-ray scattering as a contrast mechanism

Journal of Applied Crystallography ◽

10.1107/s0021889804016073 ◽

2004 ◽

Vol 37 (5) ◽

pp. 757-765 ◽

Cited By ~ 28

Author(s):

L. E. Levine ◽

G. G. Long

Keyword(s):

Small Angle ◽

Imaging Technique ◽

Three Dimensional ◽

Sample Volume ◽

Contrast Imaging ◽

X Ray ◽

X Ray Scattering ◽

X Ray Imaging ◽

Contrast Mechanism ◽

Ray Scattering

A new transmission X-ray imaging technique using ultra-small-angle X-ray scattering (USAXS) as a contrast mechanism is described. USAXS imaging can sometimes provide contrast in cases where radiography and phase-contrast imaging are unsuccessful. Images produced at different scattering vectors highlight different microstructural features within the same sample volume. When used in conjunction with USAXS scans, USAXS imaging provides substantial quantitative and qualitative three-dimensional information on the sizes, shapes and spatial arrangements of the scattering objects. The imaging technique is demonstrated on metal and biological samples.

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In situ wide-field visualization of palladium hydrogenation

10.21203/rs.3.rs-88509/v1 ◽

2020 ◽

Author(s):

Chongjun Jin ◽

Nicholas Fang ◽

Xiaoyi She ◽

Huifeng Du ◽

Yang Shen ◽

...

Keyword(s):

Real Time ◽

Hydrogen Diffusion ◽

Fast Response ◽

Wide Field ◽

Ion Diffusion ◽

Optical Contrast ◽

Self Organized ◽

Transmission Electron ◽

Kinetics Of

Abstract Visualizing hydrogenation processes in metals in real-time is important to various hydrogen-involved applications. However, observing hydrogen diffusion was limited by transmission electron microscopy, and the kinetics of hydrogenation in the interior of the metals was not reported. Here we proposed an optical microscopy-based visualization of palladium hydrogenation from diffusion surface to the interior by introducing a fast-response mechanical platform that transforms the hydrogen diffusion into self-organized ordered wrinkles with sharp optical contrast. This platform is an Au/Pd double layer on elastomer which results in directional hydrogenation from sidewall to the interior. The kinetics of hydrogenation in the interior of the palladium along the diffusion direction was monitored in real-time. This platform will enable in-situ visualization of atom/ion diffusion on metals that are crucial in energy storage and hydrogen detection.

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Electro-optic imaging enables efficient wide-field fluorescence lifetime microscopy

Nature Communications ◽

10.1038/s41467-019-12535-5 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 7

Author(s):

Adam J. Bowman ◽

Brannon B. Klopfer ◽

Thomas Juffmann ◽

Mark A. Kasevich

Keyword(s):

Temporal Resolution ◽

Single Molecule ◽

Fluorescence Lifetime ◽

Collection Efficiency ◽

Frame Rate ◽

Optical Systems ◽

Wide Field ◽

Pockels Cell ◽

Low Light ◽

Optical Efficiency

Abstract Nanosecond temporal resolution enables new methods for wide-field imaging like time-of-flight, gated detection, and fluorescence lifetime. The optical efficiency of existing approaches, however, presents challenges for low-light applications common to fluorescence microscopy and single-molecule imaging. We demonstrate the use of Pockels cells for wide-field image gating with nanosecond temporal resolution and high photon collection efficiency. Two temporal frames are obtained by combining a Pockels cell with a pair of polarizing beam-splitters. We show multi-label fluorescence lifetime imaging microscopy (FLIM), single-molecule lifetime spectroscopy, and fast single-frame FLIM at the camera frame rate with 103–105 times higher throughput than single photon counting. Finally, we demonstrate a space-to-time image multiplexer using a re-imaging optical cavity with a tilted mirror to extend the Pockels cell technique to multiple temporal frames. These methods enable nanosecond imaging with standard optical systems and sensors, opening a new temporal dimension for wide-field low-light microscopy.

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Optical design of common-aperture multispectral and polarization optical imaging system with wide field of view

Chinese Physics B ◽

10.1088/1674-1056/28/8/084201 ◽

2019 ◽

Vol 28 (8) ◽

pp. 084201

Author(s):

Xin Liu ◽

Jun Chang ◽

Shuai Feng ◽

Yu Mu ◽

Xia Wang ◽

...

Keyword(s):

Optical Imaging ◽

Imaging System ◽

Optical Design ◽

Field Of View ◽

Wide Field ◽

Wide Field Of View ◽

Optical Imaging System

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Macroscopic fluorescence-lifetime imaging of NADH and protoporphyrin IX improves the detection and grading of 5-aminolevulinic acid-stained brain tumors

Scientific Reports ◽

10.1038/s41598-020-77268-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mikael T. Erkkilä ◽

David Reichert ◽

Johanna Gesperger ◽

Barbara Kiesel ◽

Thomas Roetzer ◽

...

Keyword(s):

Brain Tumor ◽

Brain Tumors ◽

Fluorescence Lifetime ◽

Tumor Tissue ◽

Aminolevulinic Acid ◽

Protoporphyrin Ix ◽

Low Grade ◽

Wide Field ◽

Fluorescence Lifetime Imaging ◽

Lifetime Imaging

AbstractMaximal safe tumor resection remains the key prognostic factor for improved prognosis in brain tumor patients. Despite 5-aminolevulinic acid-based fluorescence guidance the neurosurgeon is, however, not able to visualize most low-grade gliomas (LGG) and infiltration zone of high-grade gliomas (HGG). To overcome the need for a more sensitive visualization, we investigated the potential of macroscopic, wide-field fluorescence lifetime imaging of nicotinamide adenine dinucleotide (NADH) and protoporphyrin IX (PPIX) in selected human brain tumors. For future intraoperative use, the imaging system offered a square field of view of 11 mm at 250 mm free working distance. We performed imaging of tumor tissue ex vivo, including LGG and HGG as well as brain metastases obtained from 21 patients undergoing fluorescence-guided surgery. Half of all samples showed visible fluorescence during surgery, which was associated with significant increase in PPIX fluorescence lifetime. While the PPIX lifetime was significantly different between specific tumor tissue types, the NADH lifetimes did not differ significantly among them. However, mainly necrotic areas exhibited significantly lower NADH lifetimes compared to compact tumor in HGG. Our pilot study indicates that combined fluorescence lifetime imaging of NADH/PPIX represents a sensitive tool to visualize brain tumor tissue not detectable with conventional 5-ALA fluorescence.

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Brown Dwarfs in the Alpha Persei Cluster

Symposium - International Astronomical Union ◽

10.1017/s0074180900210498 ◽

2003 ◽

Vol 211 ◽

pp. 163-170 ◽

Cited By ~ 2

Author(s):

John R. Stauffer ◽

David Barrado y Navascués ◽

Jerome Bouvier ◽

Nicholas Lodieu ◽

Mark McCaughrean

Keyword(s):

Optical Imaging ◽

Main Sequence ◽

Brown Dwarfs ◽

Wide Field ◽

Minimum Mass ◽

Infrared Photometry ◽

Candidate List ◽

Low Mass ◽

Alpha Persei ◽

The Imf

We have obtained a new, deep, wide-field optical imaging survey of the young Alpha Persei cluster which reveals a well-populated lower main sequence extending into the substellar mass regime. Subsequent infrared photometry confirms that most of the candidate brown dwarfs are indeed likely to be cluster members, with a predicted minimum mass of order 0.035 solar masses. We have combined the new candidate list with previous member catalogs to derive an IMF for Alpha Per; the slope of the IMF at the low mass end is α ~ 0.66. The Alpha Per IMF slope is thus very similar to that found in the Pleiades.

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