Patent ID: 8463359

Claim:
An apparatus for characterization of a three-dimensional space in a target region within a mammalian body comprising: an expandable member having two or more transducers upon the expandable member and reference sensors positioned along a catheter body proximal to the expandable member and the two or more transducers, the expandable member deliverable in a deflated state to the target region having a volume, the member adapted to inflate in the target region to at least partially fill the volume of the target region; a fluid medium having a predetermined resistivity and which is in fluid communication with an interior of the expandable member, where the two or more transducers are in communication with one another through the medium when filled within the interior; and, a microprocessor configured to calculate a distance between the two or more transducers based on the predetermined resistivity of the medium determined from a known distance between the reference sensors.