Patent ID: 8731636
Filing Date: 2014-05-20
Classification: A61B,G16H

Abstract:
1. A diagnostic method for monitoring changes in a fluid medium in a patient's head, the method comprising: positioning a transmitter at a first location on or near the patient's head, wherein the transmitter is configured to generate and transmit a time-varying magnetic field into a fluid medium in the patient's head responsive to a first signal; positioning a receiver at a second location on or near the patient's head on an opposite side of the fluid medium from the transmitter and configured to generate a second signal responsive to a received magnetic field at the receiver; transmitting from the transmitter a time-varying magnetic field into the fluid medium in the patient's head in response to the first signal; receiving at the receiver the transmitted magnetic field; generating with the receiver the second signal responsive to the received magnetic field; and determining, using a processing unit coupled with at least the receiver, a phase shift between the transmitted magnetic field and the received magnetic field for a plurality of frequencies of the transmitted time-varying magnetic field; wherein at least one of the transmitter or the receiver comprises a shielded transmission line, and wherein the shielded transmission line comprises a strip line on a printed circuit board coupled between two grounded planes, the shielded transmission line has a loop shape, and the shielded transmission line has a lowest natural resonant frequency above 200 MHz.