Yasunobu Ito

Shimadzu (Japan)

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<title>Near-infrared optical imager for cerebral blood flow and oxygenation detection</title>

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (2001)

Ichiro Oda Yukihisa Wada Sadao Takeuchi Yukio Oikawa Naojumi Sakauchi

This paper describes the theory and the apparatus on our newly developed 64 channel optical imager that enables imaging of three components, indocyanine green (ICG), oxyHb and deoxyHb. Knowledge on blood flow is obtainable using ICG as a blood flow indicator that is to be introduced via injection. ICG has a strong absorption at 805nm, therefore the changes in ICG is detectable with NIR spectroscopy separating from oxyHb and deoxyHb using proper three wavelengths. In addition to the system description, it describes an animal experiment and a phantom test for the validation study. It discusses independence features of ICG on Hb values. Using a simple quasi Lambert Beer's law, it proved the excellent separation of the three components. It also discusses the factors that affect the performance of signal separation.

Indocyanine Green

Blood oxygenation

10.1117/12.434516

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Citations (7)

Reconstructed images for oxy and deoxy hemoglobin for a phantom with varied local oxygenation using optical CT

Advances in Optical Imaging and Photon Migration (1998)

Ichiro Oda Hideo Eda Yasunobu Ito Yukio Oikawa Yukihisa Wada

Get PDF Email Share Share with Facebook Share on X Post on reddit Share with LinkedIn Add to Mendeley Add to BibSonomy Share with WeChat Get Citation Copy Citation Text I. Oda, H. Eda, Y. Ito, Y. Oikawa, Y. Wada, Y. Tsunazawa, M. Oda, K. Ohta, Y. Yamashita, and Y. Tsuchiya, "Reconstructed images for oxy and deoxy hemoglobin for a phantom with varied local oxygenation using optical CT," in Advances in Optical Imaging and Photon Migration, J. Fujimoto and M. Patterson, eds., Vol. 21 of OSA Trends in Optics and Photonics (Optica Publishing Group, 1998), paper ATuB4. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

Optical density

10.1364/aoipm.1998.atub4

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Investigation of Multilayered 20th Century Painting by THz Imaging

2022 47th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz) (2019)

Kaori Fukunaga Yoshimi Ueno Yasunobu Ito

A masterpiece of Salvador Dalí was investigated by using Terahertz time-domain imaging. The experimental results confirmed its multilayered structure and suggested that Dalí did not cover the entire canvas because the number of painted layers depends on the area. The painting was supported with a lining layer and a metal plate added in previous intervention, and its structure was compared with that of another 20th century masterpiece painted by Pablo Picasso.

PICASSO

10.1109/irmmw-thz.2019.8873825

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Citations (4)

Image Reconstruction of Phantom with plural Absorbing Rods in Optical CT

Advances in Optical Imaging and Photon Migration (1996)

Hideo Eda Ichiro Oda Yasunobu Ito Yukihisa Wada

Reconstructed images of Cylindrical phantom with plural absorbing rods are presented. TEAM/FBP gives best spatial resolution. CW/Weight gives better in accuracy of absorption coefficient.

Plural

Rod

10.1364/aoipm.1996.ria290

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Citations (1)

Visuospatial imagery is a fruitful for the digit span backward task: a study with near-infrared optical tomography

NeuroImage (2000)

Yoko Hoshi Ichiro Oda Yukihisa Wada Yasunobu Ito Yutaka Yamashita

Numerical digit

Memory span

10.1016/s1053-8119(00)91303-x

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<title>Optical imaging of hemoglobin distribution in human skin</title>

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (2001)

Manami Kobayashi Yasunobu Ito Naojumi Sakauchi Ichiro Oda Ikuo Konishi

We have developed a new four-wavelength optical imager to evaluate the oxygen supply in human skin for peripheral circulation. It measures the reflected light from human skin by a CCD and presents the maps of hemoglobin distribution. This paper describes the principle, system configuration and performance test for human foot during and after venous and arterial occlusion. The obtained images showed distinct local difference in skin oxygenation due to blood flow.

Human skin

Blood supply

Blood circulation

10.1117/12.447423

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Citations (3)

Optical imaging of hemoglobin distribution in human skin

Manami Kobayashi Yasunobu Ito Naofumi Sakauchi Ichiro Oda Ikuo Konishi

Human skin

Blood supply

Blood circulation

10.1364/ecbo.2001.4431_199

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Analysis of nonlinear relation for skin hemoglobin imaging

Optics Express (2001)

Manami Kobayashi Yasunobu Ito Naofumi Sakauchi Ichiro Oda Ikuo Konishi

This paper discusses the accuracy of the optical determination of the oxygenated and deoxygenated hemoglobin content of human skin under the influence of a melanin layer for a multi-wavelengths imager. The relation between the nonlinear results by Monte Carlo simulation (MCS) and the modified Lambert Beer's law (MLB) is also clarified, emphasizing the importance of the absolute values of skin pigments and their influence on the mean path-length used in MLB. The fitting procedure of the MCS data to the actual skin spectra is shown to obtain the absolute values. It is also shown that once the proper mean path-lengths have been determined, MLB can be used fairly well within an accuracy of 80% compared with MCS. Images of oxygenated hemoglobin with a newly-developed fourwavelength camera are presented to demonstrate the advantages of a multiwavelength system.

Deoxygenated Hemoglobin

Beer–Lambert law

10.1364/oe.9.000802

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Citations (39)

<title>Noninvasive hemoglobin oxygenation monitor and computed tomography by NIR spectrophotometry</title>

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (1991)

Ichiro Oda Yasunobu Ito Hideo Eda Tomomi Tamura Michinosuke Takada

Using a near infrared (NIR) spectrophotometry, a compact instrument for monitoring the hemoglobin (Hb) oxygenation state in human brain was developed. Brian oxygen metabolism was non-invasively studied by simultaneous measurement of oxygenated Hb, deoxygnated Hb and total Hb content in rat and human head. After evaluating our method using anesthetized and artificially ventilated rats, this instrument was applied for clinical use, and was useful for the management of clinical patients. The same method was applied to develope the NIR computed tomography (CT). Human X-ray CT was modified for NIR-CT, and CT images were obtained using the back-projection (BP) method. NIR-CT could measure the oxygenation map of the tissues of anesthetized rats.

Spectrophotometry

Oxygen metabolism

10.1117/12.44199

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Citations (18)

Nondestructive observation of multilayered modern paintings by electromagnetic waves

Kaori Fukunaga Yoshimi Ueno Yasunobu Ito

Electromagnetic waves from microwave to X-ray have been used in heritage science research filed. We have examined masterpieces of modern paintings among collections of the Ikeda Museum of 20th Century Art in Japan, by using THz time-domain imaging, near-infrared camera, and X-ray fluorescence, depending on the points to be discussed. An oil painting by Salvador Dalí has been mounted on aluminium plate for conservation purpose in the 20th century. THz imaging revealed multiple painting layers and thick supporting layers on the aluminium plate. Infrared imaging of a gouache painting by Marc Chagall clearly shows underdrawings. X-ray fluorescence method is applied to investigate paints used by Joan Miró, and successfully distinguished two white pigments.

Conservation

10.1117/12.2530142

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