Current dipole estimation from magnetospinogram with 3-D planar sensor array

Magnetspinogram(MSG) is an electrical diagnosis method for myelopathy, symptom by fault of spinal nerve. It is one of the promising technique to locate spinal cord legion by detecting nerve activities. Since the nerve activities are hard to detect on body surface electrode as in electroencephalogram(EEG), 3-D biomagnetic superconducting quantum interference device(SQUID) sensors are in clinical use. This paper describes application of a direct current dipole estimation method succeeded in magnetoencephalogram(MEG) to MSG processing. Since MSG does not have the electrical counter part, electrospinogram(ESG), due to low SNR, a closed and explicit description of volume current field is required, and we introduce strict derivation by using Green's function.