Proceedings ArticleDOI
UCL multichannel time-resolved system for optical tomography
Kevin Wells,Jeremy C. Hebden,Florian E. W. Schmidt,David T. Delpy +3 more
- Vol. 2979, pp 599-607
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TLDR
In this article, a multichannel time resolved imaging system was developed at University College London (UCL) suitable for optical tomography of the human breast and neonatal brain.Abstract:
A multichannel time resolved imaging system is being developed at University College London (UCL) suitable for optical tomography of the human breast and neonatal brain. The system utilizes the time correlated single photon counting technique, operating in reverse start-stop mode. The detectors are custom made multi-anode microchannel plate photomultipliers (Hamamatsu R411OU-05MOD). Signal processing is implemented using fast NIM logic, and the system is based upon the ORTEC 9308-D picosecond time analyzer in place of a conventional time to amplitude converter. The system is designed to acquire 32 channels of time-resolved data simultaneously, with sub-100 ps temporal resolution, and at count rates of at least 2 multiplied by 104 photons per second per channel. This paper discusses the theoretical considerations which led to the final design, and describes the detector and electronic hardware on which the system is based.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.read more
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A 32-channel time-resolved instrument for medical optical tomography
TL;DR: A prototype multichannel time-resolved medical optical tomography system is presented, and the effectiveness of this instrument is demonstrated by successfully imaging a tissue-equivalent phantom.
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Iterative reconstruction scheme for optical tomography based on the equation of radiative transfer.
TL;DR: An iterative image reconstruction scheme for optical tomography that is based on the equation of radiative transfer that accurately describes the photon propagation in turbid media without any limiting assumptions regarding the optical properties is reported on.
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Optical tomographic imaging of dynamic features of dense-scattering media
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Sensors and measurements in solid state fermentation: a review
TL;DR: Current on-line methods and innovative applications of methods with a potential to measure parameters in SSF, including aroma sensing, infrared spectrometry, artificial vision, and tomographic techniques are explored.
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Spatial and temporal analysis of human motor activity using noninvasive NIR topography
Atsushi Maki,Yuichi Yamashita,Yoshitoshi Ito,Eiju Watanabe,Yoshiaki Mayanagi,Hideaki Koizumi +5 more
TL;DR: It was found that the regional change in cerebral blood volume in the primary motor area overlaps the global change around the motor cortex.
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Experimental images of heterogeneous turbid media by frequency-domain diffusing-photon tomography.
TL;DR: To the knowledge, the images are the first experimental reconstruction based on data collected in the frequency domain, and it is shown that this method is sensitive to the optical properties of the heterogeneity.
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Spatially varying optical property reconstruction using a finite element diffusion equation approximation
Keith D. Paulsen,Huabei Jiang +1 more
TL;DR: Results using simulated data suggest that qualitative images can be produced that readily highlight the location of absorption and scattering heterogeneities within a circular background region of close to 4 cm in diameter over a range of contrast levels, suggesting that absolute optical imaging involving simultaneous recovery of both absorption and scatter profiles in multicentimeter tissues geometries may prove to be extremely difficult.
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Dynamic multichannel near-infrared optical imaging of human brain activity
Yoko Hoshi,Mamoru Tamura +1 more
TL;DR: In this paper, a maximal five-channel optical monitoring system was used to detect region-specific changes in both the hemoglobin oxygenation state and blood volume during various mental tasks, in addition to visual and auditory stimulation.