Patent ID: 7758587

Claim:
An apparatus for determining the orientation of a medical device within a patient's body, comprising: a catheter having a tube wall defining a lumen therethrough, wherein the catheter is radiopaque under x-ray fluoroscopy; and a plurality of tube wall bending indicators located at least on or within the catheter wall at a reference portion of the catheter to become curved where the catheter passes through an anatomical reference when the distal end of the catheter is at a target site within the patient's body; wherein the plurality of tube wall bending indicators provide an indication of tube wall bending to indicate the orientation of the reference portion of the catheter relative to the anatomical reference; wherein the tube wall bending indicators comprises: a plurality of strain gauges for providing said indication of tube wall bending by changing an electrical resistance in accordance with an amount of tube wall bending within the vicinity of each strain gauge.