PROCESS FOR THE STUDY OF INTERNAL PHYSIOLOGICAL PHENOMENA

摘要

1416335 Electro-medical apparatus J DUROUX 3 Nov 1972 [15 Nov 1971] 50831/72 Heading G1N Physiological phenomena are investigated by subjecting the body to an electromagnetic field having a frequency of at least 10 kHz, this frequency being regulated to determine the volume of body to be investigated, sensing and measuring at least one component of the field in the vicinity of the volume by means of a field pick-up in contact with the body, calculating an impedance function based on the measurement, and registering this function. The source of the field is preferably a magnetic dipole consisting of a search coil having a current passed therethrough. An electric dipole may alternatively be used. The coil may be arranged at a distance from the surface of the body with the coils in a plane at right-angles to the surface or it may be arranged on the body either perpendicular or parallel to the body surface. The components which may be measured are the magnetic field components Hx, Hy, Hz using pick-up coils 4, 10, and the electric field components Ex, Ey, Ez using pick-up electrodes 3. Various orientations are described with reference to Figs. 3-12 (not shown). Alternatively the phase shift of the various components relative to the field or the in-phase or quadrature components may be measured. As shown in Fig. 2, the electrodes 3 and the coils 4, 10 are each connected to a respective filter and amplification chain 5, 6, 11 whose outputs are applied to a calculator 7 whose output is applied directly to a register 8 and to the register via a shunt 9 which provides a differential with respect to time. Various impedance functions determined by the calculator from the measured values are given. The phenomena which may be investigated include, pulmonary ventilation, respiratory frequency, cardiac output, the water content of the extravascular sector, lungs or peripheral interstitial tissue, circulation in the kidneys, brain, a limb or any other part of the body.