Page 8 - LifeScience Solution for FNIRS
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            Neurorehabilitation                                                                                                       Comparison of fNIRS and fMRI                                                                              Light to Measure Brain Function  Principle of Using Near Infrared






            Example of Brain-Function Imaging Research: Neurorehabilitation Application Research                                      Example of Brain-Function Imaging Research: Comparison of fNIRS and fMRI


               Data                                                                                                                     Data                                                                                                    Imaging  Optical Brain-Function

               In recent years, progress has been made in researching the use of fNIRS in neurorehabilitation applications, such as during or after a                                   A: Measurement by fMRI
               stroke.                                                                                                                     A                     B
               PET and fMRI systems require the subject to be at rest, but fNIRS systems can measure brain function even while the subject is                                           Clearly shows activity in motor cortex for opposite side due to   bilitation  Neuroreha-
                                                                                                                                                                                        exercise (grasping). The lower BOLD* signal shows an increase
               performing tasks that involve body movement. Therefore, it can be used to obtain information about cerebral activity associated with
                                                                                                                                                                                        during the task (blue).
               walking or other movement.
                                                                                                                                                                                        B: Measurement by fNIRS
                                                                      Irradiation
                                                                                                                                                                                        Displays results from 2D mapping (overlaid on MRI image) of
                                                                      Detection                                                                                                         Deoxy-Hb and Oxy-Hb during exercise. The lower graph shows the   fNIRS and fMRI  Comparison of
                                                                                                                                                                                        change in Oxy-Hb and Deoxy-Hb in the motor cortex (marked with
                                                                                                                                                                                        circles). It shows how Oxy-Hb and Total-Hb increase and Deoxy-Hb
                                                                                                                                                                                        decreases during the task (40 sec).


                                                         Walk Walk Walk Walk Walk                                                                                                                                                               Motor Control  Brain Activity during
                                                                                                                                                                                                             * BOLD: Blood Oxygen Level Dependent
                                                                                                                                         Comparison of BOLD-fMRI (A) and fNIRS (B) for Normal Healthy Subject

                                                                                                                                                                                        Since fNIRS is not affected by electrical noise or magnetic fields
                                                                                                                                           C                     D                                                                              Measurement with EEG  Simultaneous
                                                                                                                                                                                        and has few limitations on patient posture during measurements,
                                           fNIRS Measurement of Brain Activation while Walking on a Treadmill
                                                                                                                                                                                        it can be used to measure brain function in cases where
                                                                                                                                                                                        BOLD-fMRI cannot be used, such as on subjects being treated with
                                                Walk     Swinging Arms  Leg Movement  Visualizing Walking                                 Tremor(+)                                     deep brain stimulation (DBS) using a metal electrode.

                                                                                                                                                                                        C: fNIRS Image (overlaid on MRI image) of               Analysis Method  NIRS Signal
                                                                                                                                                                                            Essential Tremor Subject Being Treated with DBS
                                                                                                                                                                                        1. With Electrical Stimulation of DBS OFF (upper graph)
                                                                                                                                          Tremor(-)                                     Oxy-Hb increased significantly and Deoxy-Hb also increased,
                                 fNIRS
                                                                                                                                                                                        primarily in the right motor cortex, when a strong tremor occurred
                                                                                                                                                                                        in the upper left extremity during a finger-to-finger test.   Inner Speech  Investigating
                                                                                                                                                                                        (The increase in Deoxy-Hb indicates an abnormal enhanced release
                                                                                                                                                                                        of oxygen metabolites.)
                                                                                                                                                                                        2. With Electrical Stimulation of DBS ON (lower graph)
                                                                                                                                                    fNIRS Measurement of Change in      The tremor did not occur during the finger-to-finger test and the
                                                                                                                                               Active Brain Oxygen Metabolites in Tremor Subject
                                                                                                                                                                                        increase in Deoxy-Hb disappeared.                       Functions  Language Processing
                                                            fMRI
                                                                                                                                                                                        D: Change in Oxy-Hb, Deoxy-Hb, and Total-Hb
                                                                                                                                                                                             Levels During Movement Task
                                           Brain Activity for Healthy Person during walking and Related Tasks

               The above shows the brain activity measured while walking on a treadmill. It shows an increase in Oxy-Hb associated with walking,                                                                                                Research  Mental Disorder
                                                                                                                                        Since fNIRS can measure not only Deoxy-Hb, but also changes in Oxy-Hb and blood flow, it is especially well suited to imaging brain
               inner side of the primary sensorimotor cortex, near the center. fNIRS is able to measure brain activity during dynamic movements
                                                                                                                                        function in subjects where brain oxygen metabolite activity and hemodynamics are not normal. Currently, BOLD-fMRI is the primary
               assigned as tasks, such as walking or arm swinging, which cannot be measured using fMRI and PET. It can also be used to assess
                                                                                                                                        method used to image brain function, but using it in conjunction with fNIRS allows accurately imaging brain function.
               brain activity at the bedside. fNIRS is being used in research to evaluate brain activity during hemiplegic gait by stroke subjects, to
               improve asymmetry in the activity of the sensorimotor cortex, increase activity in the premotor cortex, improve walking, etc.                                                                                                    Shimadzu fNIRS   Key References Regarding
               (Data provided by: Mr. Ichiro Miyai, Morinomiya Hospital, Omichi-kai Medical Corporation)                                (Data provided by: Mr. Kaoru Sakatani, Department of Neurological Surgery, Nihon University School of Medicine)
               Reference: Miyai, I., (2004). "Application of fNIRS in Neurorehabilitation." MEDICAL NOW, No. 52: 33-36.                 Reference: Sakatani, K., (2006) "Imaging Brain-Function of Patients with Encephalopathy: Comparison of fNIRS and fMRI," MEDICAL NOW, No.59: 44-46.




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