Development of new-designed device ("simultaneous transcranial measurement system of multiple electrical pulse impedances using multi-polar circuit method") to measure local cerebral blood flow

2005 Fiscal Year Final Research Report Summary

• Project/Area Number: 15591516
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Cerebral neurosurgery
• Research Institution: Hamamatsu University School of Medicine
• Principal Investigator: NISHIZAWA Shigeru Hamamatsu University School of Medicine, Neurosurgery, associate professor, 医学部, 助教授 (40135257)
• Co-Investigator(Kenkyū-buntansha): TAKEMAE Tadashi Shizuoka University, Faculty of Engineering, Professor, 工学部, 教授 (20115356) ; NAMBA Hiroki Hamamatsu University School of Medicine, Neurosurgery, Professor, 医学部, 教授 (60198405)
• Project Period (FY): 2003 – 2005
• Keywords: magnetic field / electrical impedance / cerebral blood flow / less invasive / tetra-polar circuit method

Research Abstract

We newly designed and developed a system ("simultaneous transcranial measurement system of multiple electrical pulse impedances using multi-polar circuit method") to measure multi-point local cerebral blood flow. Actually, 8 points of local cerebral blood flow can be measured transcranially. The system rotates around the head and electrical impedance is measured at each point.
We loaded three different kinds of task forces, such as light stimulation, loading of CO2, and pointing of difference between similar figures. In the test of pointing of difference between similar figures, impedance detected from bilateral temporo-occipital areas were significantly changed. In the light stimulation, such change was detected in occipital areas. In the loading of CO2, impedance change in the whole area was found.
We tried these tests using animal model, and examined the impedance change, which was obtained in volunteers, would also found in the animal model, and also tested the relation between the impedance change and change of intracranial pressure. However, it took unexceptionally longer time to establish the same system for animal experiment, and we did not get good results in the animal experimental model yet.
In near future, we will finish to produce the same system for animal experiment, and try this system to the experimental animal, and examine weather the results using this system for volunteers represent real change of local cerebral blood flow or not.