Title :
Instrumentation for the non-invasive direct measurement of skull impedance
Author :
Seagar, Andrew ; Chen, Dong
Author_Institution :
Sch. of Biophys. Sci. & Electr. Eng., Swinburne Univ. of Technol., Hawthorn, Australia
Abstract :
A model is presented for the local flow of electric current, based on the known electrical properties of the tissues which comprise the human head. It is applied to the design of an instrument for the direct non-invasive measurement of the skull´s impedance, addressing the need for exceedingly high impedances at frequencies in the 10 to 100 kHz range. It is shown how the design achieves impedances in excess of those of the usually achieved with operational amplifiers, even when their open loop gains are strictly limited. The performance characteristics of a hardware realisation of the design are presented
Keywords :
bioelectric phenomena; biomedical equipment; bone; electric impedance measurement; physiological models; 10 to 100 kHz; electric current local flow model; hardware realisation; human head; medical instrumentation; noninvasive direct measurement instrumentation; open loop gains; operational amplifiers; performance characteristics; skull impedance; tissue electrical properties; Current measurement; Electric resistance; Electric variables measurement; Electrical resistance measurement; Frequency; Immune system; Impedance measurement; Instruments; Scalp; Skull;
Conference_Titel :
Bioelectromagnetism, 1998. Proceedings of the 2nd International Conference on
Conference_Location :
Melbourne, Vic.
Print_ISBN :
0-7803-3867-7
DOI :
10.1109/ICBEM.1998.666416
