METHOD AND DEVICE FOR INVESTIGATING BRAIN STATE Russian patent published in 2001 - IPC

FIELD: medicine; medical engineering. SUBSTANCE: method involves applying brain tissue impedance-measuring techniques with electromagnetic resonance method at three frequencies. Volume impedance of the head is measured at the lowest frequency with patient head placed into the inductance coil field which winding is mounted on cylindrical carcass. Volume impedance of the head zones is measured at the middle frequency range with the inductance coil placed on the zones, the coil winding being mounted on flat curved carcass. Volume impedance of the head zones is measured at the highest frequency with the inductance coil placed on the zones, the coil winding being mounted on flat carcass. Active and reactive impedance components are measured in every case and the obtained results are compared to some reference values. Parameter differences are interpreted in terms of brain state in different frequency zones. The device has sinusoid oscillator, transducer unit and recorder unit. Potential outlet lead of the oscillator is connected to potential inlet lead of the transducer unit through capacitor. The transducer unit is designed as parallel oscillatory circuit and has measuring inductance coil winding, constant capacity capacitor member two variable capacity capacitor members. All the components are connected in parallel. The oscillatory circuit outlets are connected to buffer amplifier inlet which outlet is connected to recorder inlet. Oscillator outlets are connected through two capacitors to additional leads having measuring metal electrodes connectable by means of conductors. Circuit composed of variable resistor and two-positioned switch connected in series is connected in series to oscillatory circuit outlets. The device has three inductance coils of which the first is designed as cylindrical coil, which windings are mounted on plastic solid dielectric carcass having circular or oval cross- section. The second coil has spiral-shaped winding mounted on flat curved carcass from solid dielectric as radially arranged leaves with gap. Winding wire envelopes in turn the neighboring leaves from opposite sides, the number of leaves being odd. The third coil has spiral- shaped winding mounted on flat carcass from solid dielectric as radially arranged leaves with gap. Winding wire envelopes in turn the neighboring leaves from opposite sides, the number of leaves being odd. The third coil has spiral-shaped winding mounted on flat curved carcass from solid dielectric as radially arranged leaves with gap. Winding wire envelopes in turn the neighboring leaves from opposite sides, the number of leaves being odd. EFFECT: wide range of applications; noninvasive method of application; prevented complications. 3 cl, 2 dwg