By using a multiple receiving coil composed of receiving coils, an imaging portion of a subject is subjected to a first pulse sequence to create n sensitivity images (701 to 703) fewer than the examination images. When these sensitivity images are created, an NMR signal is measured for only the low-frequency region of the k space. A second pulse sequence from which a phase encode step is removed is conducted to create m (m>n) examination images (704, 705) of the subject by using the receiving coils. When sensitivity distributions (707, 708) of the receiving coils are determined for the sensitivity images (701 to 703), and if there are no sensitivity distributions corresponding to the slice positions of the examination images (704, 705), they are determined by slice interpolation using the sensitivity distributions (701 to 703), and the aliasing artifacts of the examination images (704, 705) are removed by matrix operation by using the sensitivity distributions (707, 708).

Magnetic resonance imaging device

http://www.iss.com/resources/pdf/publications/fnirs-history.pdf

A brief review on the history of human functional near-infrared spectroscopy (fNIRS) development and fields of application.

A review on continuous wave functional near-infrared spectroscopy and imaging instrumentation and methodology.

We review the current state-of-the-art of diffuse optical imaging, which is an emerging technique for functional imaging of biological tissue. It involves generating images using measurements of visible or near-infrared light scattered across large (greater than several centimetres) thicknesses of tissue. We discuss recent advances in experimental methods and instrumentation, and examine new theoretical techniques applied to modelling and image reconstruction. We review recent work on in vivo applications including imaging the breast and brain, and examine future challenges.

https://iopscience.iop.org/article/10.1088/0031-9155/50/4/R01/pdf

Recent advances in diffuse optical imaging.

Near-infrared spectroscopy (NIRS) is a noninvasive neuroimaging tool for studying evoked hemodynamic changes within the brain. By this technique, changes in the optical absorption of light are recorded over time and are used to estimate the functionally evoked changes in cerebral oxyhemoglobin and deoxyhemoglobin concentrations that result from local cerebral vascular and oxygen metabolic effects during brain activity. Over the past three decades this technology has continued to grow, and today NIRS studies have found many niche applications in the fields of psychology, physiology, and cerebral pathology. The growing popularity of this technique is in part associated with a lower cost and increased portability of NIRS equipment when compared with other imaging modalities, such as functional magnetic resonance imaging and positron emission tomography. With this increasing number of applications, new techniques for the processing, analysis, and interpretation of NIRS data are continually being developed. We review some of the time-series and functional analysis techniques that are currently used in NIRS studies, we describe the practical implementation of various signal processing techniques for removing physiological, instrumental, and motion-artifact noise from optical data, and we discuss the unique aspects of NIRS analysis in comparison with other brain imaging modalities. These methods are described within the context of the MATLAB-based graphical user interface program, HomER, which we have developed and distributed to facilitate the processing of optical functional brain data.

/pdf/homer-a-review-of-time-series-analysis-methods-for-near-4ln9n7d315.pdf

HomER: a review of time-series analysis methods for near-infrared spectroscopy of the brain.

Non-invasive assessment of language dominance with near-infrared spectroscopic mapping

Practicality of wavelength selection to improve signal-to-noise ratio in near-infrared spectroscopy

Near infrared spectroscopic topography (NIRS) is widely recognized as a noninvasive method to measure the regional cerebral blood volume (rCBV) dynamics coupled with neuronal activities. We analyzed the rCBV change in the early phase of epileptic seizures in 12 consecutive patients with medically intractable epilepsy. Seizure was induced by bemegride injection. We used eight-channel NIRS in nine cases and 24 channel in three cases. In all of the cases, rCBV increased rapidly after the seizure onset on the focus side. The increased rCBV was observed for about 30-60 s. The NIRS method can be applied to monitor the rCBV change continuously during seizures. Therefore, this method may be combined with ictal SPECT as one of the most reliable noninvasive methods of focus diagnosis.

https://www.spiedigitallibrary.org/journals/Journal-of-Biomedical-Optics/volume-5/issue-03/0000/Non-invasive-cerebral-blood-volume-measurement-during-seizures-using-multi/10.1117/1.429998.pdf

Noninvasive cerebral blood volume measurement during seizures using multichannel near infrared spectroscopic topography.

In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.

Optical system for measuring metabolism in a body and imaging method

In a radiation detector, scintillation material flouoresces and the produced light is converted to electrical energy in an adjacent converter, separators are provided in spaces between the adjacent scintillators and converters. The separators may have a greater length than the adjacent scintillators, so that they will extend beyond to reduce cross-talk. The separators can extend toward the source of radiation for a height substantially greater than, and particularly five times, the height of the spaces between the adjacent scintillators to prevent X-ray scattering and function as a collimator. Optically opaque adhesive may be provided on the opposite ends of separators and pairs of scintillators and collimators, to prevent cross-talk.

Fumio Kawaguchi

Papers

Non-invasive assessment of language dominance with near-infrared spectroscopic mapping

Practicality of wavelength selection to improve signal-to-noise ratio in near-infrared spectroscopy

Noninvasive cerebral blood volume measurement during seizures using multichannel near infrared spectroscopic topography.

Optical system for measuring metabolism in a body and imaging method

Multi-element radiation detector