Abstract: A tissue testing chamber having a hollow, electrically insulative housing separable into two parts or halves, each half including a plate-like working electrode and spaced therefrom an annular measuring electrode, with electrical leads provided to each of the electrodes for interconnection with external control and measuring equipment. Each housing half or test chamber half has a cavity communicating with both the working and measuring electrodes and an open end. The housing halves clamp the test specimen between them. A quantity of Ringer's solution is added to each housing cavity and the four electrodes are then connected in a four electrode impedance bridge with selectively variable impedances (e.g., capacitance) which on bridge balance provides capacitance of specimen.

Abstract: Two probes for tissue impedance measurement each have first and second conductive rings unitarily arranged with an insulative member separating the rings. The conductive rings are coaxially arranged and have individual lead wires connected thereto which extend from one end of the probe for connection to external processing and measuring equipment. One probe is of a size enabling insertion within a blood vessel while the other is for location in an epithelial cavity. In use an alternating test signal is applied to the electrodes of each probe and measurements are taken between the two sets of measuring electrodes determining the impedance of the cavity wall tissue lying between the two probes without passing current through the tissue.

Abstract: Two probes for tissue impedance measurement each have first and second conductive rings unitarily arranged with an insulative member separating the rings. The conductive rings are coaxially arranged and have individual lead wires connected thereto which extend from one end of the probe for connection to external processing and measuring equipment. One probe is of a size enabling insertion within a blood vessel while the other is for location in an epithelial cavity. In use an alternating test signal is applied to the electrodes of each probe and measurements are taken between the two sets of measuring electrodes determining the impedance of the cavity wall tissue lying between the two probes without passing current through the tissue.