Abstract: A portion of a concentric bipolar microelectrode sensor is attached to an inflatable balloon of a catheter. Another portion of the concentric bipolar microelectrode sensor is also attached to a body of the catheter. The inflatable balloon is guided to become in proximity of a tissue. The inflatable balloon is then inflated. The inflation increases the likelihood of contact between microelectrodes of the concentric bipolar microelectrode sensor with the tissue. A voltage is supplied to the microelectrodes. The tissue's impedance is accordingly measured over a frequency range. A disease of the tissue, such as a lesion, is diagnosed based on the measured impedance.

Abstract: A portion of a concentric bipolar microelectrode sensor is attached to an inflatable balloon of a catheter. Another portion of the concentric bipolar microelectrode sensor is also attached to a body of the catheter. The inflatable balloon is guided to become in proximity of a tissue. The inflatable balloon is then inflated. The inflation increases the likelihood of contact between microelectrodes of the concentric bipolar microelectrode sensor with the tissue. A voltage is supplied to the microelectrodes. The tissue's impedance is accordingly measured over a frequency range. A disease of the tissue, such as a lesion, is diagnosed based on the measured impedance.

Abstract: A micromachined sensor for measuring vascular parameters, such as fluid shear stress, includes a substrate having a front-side surface, and a backside surface opposite the front-side surface. The sensor includes a diaphragm overlying a cavity etched within the substrate, and a heat sensing element disposed on the front-side surface of the substrate and on top of the cavity and the diaphragm. The heat sensing element is electrically couplable to electrode leads formed on the backside surface of the substrate. The sensor includes an electronic system connected to the backside surface and configured to measure a change in heat convection from the sensing element to surrounding fluid when the sensing element is heated by applying an electric current thereto, and further configured to derive from the change in heat convection vascular parameters such as the shear stress of fluid flowing past the sensing element.