Patent ID: 6216027
Filing Date: 2001-04-10
Classification: A61B,A61N

Abstract:
A method of establishing anatomical landmarks within a living body, comprising the steps of:(a) providing a reference catheter having a plurality of ultrasound reference transducers, each reference transducer capable of transmitting and receiving ultrasound signals;(b) providing a marking catheter having an ultrasound target transducer;(c) positioning the reference catheter and the marking catheter within the living body and positioning the distal tip of the marking transducer adjacent to an anatomical structure within the body;(d) causing a plurality of the transducers to emit ultrasound signals for receipt by others of the transducers, including causing reference transducers to receive ultrasound signals emitted by others of the reference transducers;(e) measuring the elapsed time between transmission of each ultrasound signal emitted in step (d) and its receipt by others of the transducers, and using the measured elapsed times to determine the relative distances between the transducers;using distances determined in step (e), establishing the three-dimensional arrangement of the reference transducers to establish a coordinate system within the body, and determining the location of the target transducer relative to the coordinate system;(g) deriving the location of the anatomical landmark using the location of the target transducer determined in step (f); and(h) displaying the three-dimensional position of the anatomical landmark relative to the coordinate system on a graphical display.