Recent Advances in Contrast-Enhanced near Infrared Diffuse Optical Imaging of Diseases Using Indocyanine Green

Contrast-enhanced near-infrared spectroscopy (NIRS) with indocyanine green (ICG) can be a valid non-invasive, continuous, bedside neuromonitoring tool. However, its usage in moderate and severe traumatic brain injury (TBI) patients can be unprecise due to their clinical status. This review is targeted at researchers and clinicians involved in the development and application of contrast-enhanced NIRS for the care of TBI patients and can be used to design future studies. This review describes the methods developed to monitor the brain perfusion and the blood–brain barrier integrity using the changes of diffuse reflectance during the ICG passage and the results on studies in animals and humans. The limitations in accuracy of these methods when applied on TBI patients and the proposed solutions to overcome them are discussed. Finally, the analysis of relative parameters is proposed as a valid alternative over absolute values to address some current clinical needs in brain trauma care. In conclusion, care should be taken in the translation of the optical signal into absolute physiological parameters of TBI patients, as their clinical status must be taken into consideration. Discussion on where and how future studies should be directed to effectively incorporate contrast-enhanced NIRS into brain trauma care is given.

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Improved Speciation Characteristics of PEGylated Indocyanine Green-Labeled Panitumumab: Revisiting the Solution and Spectroscopic Properties of a Near-Infrared Emitting anti-HER1 Antibody for Optical Imaging of Cancer

Bioconjugate Chemistry ◽

10.1021/bc100336b ◽

2010 ◽

Vol 21 (12) ◽

pp. 2305-2312 ◽

Cited By ~ 20

Author(s):

Aaron Joseph L. Villaraza ◽

Diane E. Milenic ◽

Martin W. Brechbiel

Keyword(s):

Indocyanine Green ◽

Optical Imaging ◽

Near Infrared ◽

Spectroscopic Properties

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In Vivo Resolution of Multiexponential Decays of Multiple Near-Infrared Molecular Probes by Fluorescence Lifetime-Gated Whole-Body Time-Resolved Diffuse Optical Imaging

Molecular Imaging ◽

10.2310/7290.2007.00020 ◽

2007 ◽

Vol 6 (4) ◽

pp. 7290.2007.00020 ◽

Cited By ~ 31

Author(s):

Walter Akers ◽

Frederic Lesage ◽

Dewey Holten ◽

Samuel Achilefu

Keyword(s):

Optical Imaging ◽

Fluorescence Lifetime ◽

Fluorescence Intensity ◽

Near Infrared ◽

Molecular Probes ◽

Whole Body ◽

Diffuse Optical Imaging ◽

Fluorescence Lifetimes ◽

Time Resolved

The biodistribution of two near-infrared fluorescent agents was assessed in vivo by time-resolved diffuse optical imaging. Bacteriochlorophyll a (BC) and cypate-glysine-arginine-aspartic acid-serine-proline-lysine-OH (Cyp-GRD) were administered separately or combined to mice with subcutaneous xenografts of human breast adenocarcinoma and slow-release estradiol pellets for improved tumor growth. The same excitation (780 nm) and emission (830 nm) wavelengths were used to image the distinct fluorescence lifetime distribution of the fluorescent molecular probes in the mouse cancer model. Fluorescence intensity and lifetime maps were reconstructed after raster-scanning whole-body regions of interest by time-correlated single-photon counting. Each captured temporal point-spread function (TPSF) was deconvolved using both a single and a multiexponental decay model to best determine the measured fluorescence lifetimes. The relative signal from each fluorophore was estimated for any region of interest included in the scanned area. Deconvolution of the individual TPSFs from whole-body fluorescence intensity scans provided corresponding lifetime images for comparing individual component biodistribution. In vivo fluorescence lifetimes were determined to be 0.8 ns (Cyp-GRD) and 2 ns (BC). This study demonstrates that the relative biodistribution of individual fluorophores with similar spectral characteristics can be compartmentalized by using the time-domain fluorescence lifetime gating method.

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CONTRAST-ENHANCED PHOTOACOUSTIC IMAGING USING INDOCYANINE GREEN-CONTAINING NANOPARTICLES

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545813500296 ◽

2014 ◽

Vol 07 (01) ◽

pp. 1350029 ◽

Cited By ~ 13

Author(s):

JUNPING ZHONG ◽

SIHUA YANG

Keyword(s):

Indocyanine Green ◽

Contrast Agents ◽

Near Infrared ◽

Photoacoustic Imaging ◽

Signal Amplitude ◽

Photoacoustic Signal ◽

Infrared Wavelength ◽

Contrast Enhanced ◽

Human Use ◽

Good Contrast

Contrast agents are attracting a great deal of attention in photoacoustic imaging. Here we introduce an exogenous contrast agent that provides high photoacoustic signal amplitude at the near-infrared wavelength. Our agents consist of Indocyanine green (ICG) and phospholipid–polyethylene glycol (PL–PEG), entitled ICG–PL–PEG nanoparticles. These nanoparticles have overcome numerous limitations of ICG, such as poor aqueous stability, concentration-dependent aggregation and lack of target specificity. ICG–PL–PEG nanoparticles are biocompatible and relatively nontoxic. All the components of ICG–PL–PEG nanoparticles have been approved for human use. Upon pulsed laser irradiation, the nanoparticles are more efficient in producing photoacoustic waves than ICG alone. The results showed that ICG–PL–PEG nanoparticles act as good contrast agents for photoacoustic imaging. These unique ICG–PL–PEG nanoparticles have great potential in clinical applications.

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Diffuse optical imaging

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2009.0080 ◽

2009 ◽

Vol 367 (1900) ◽

pp. 3055-3072 ◽

Cited By ~ 101

Author(s):

Adam Gibson ◽

Hamid Dehghani

Keyword(s):

Optical Imaging ◽

Near Infrared ◽

State Of The Art ◽

Imaging Technique ◽

Multimodality Imaging ◽

Natural Extension ◽

Psychological Research ◽

Functional Brain Imaging ◽

Diffuse Optical Imaging ◽

Image Reconstruction Techniques

Diffuse optical imaging is a medical imaging technique that is beginning to move from the laboratory to the hospital. It is a natural extension of near-infrared spectroscopy (NIRS), which is now used in certain niche applications clinically and particularly for physiological and psychological research. Optical imaging uses sophisticated image reconstruction techniques to generate images from multiple NIRS measurements. The two main clinical applications—functional brain imaging and imaging for breast cancer—are reviewed in some detail, followed by a discussion of other issues such as imaging small animals and multimodality imaging. We aim to review the state of the art of optical imaging.

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