04173228 is referenced by 334 patents and cites 6 patents.

A system for detecting and monitoring the position of a catheter tip during insertion and after placement of the catheter in a body cavity. A coupling means such as an inductor coil is secured adjacent the catheter tip, and leads extend from the coil along the catheter for connection to external indicating equipment. Energy is propagated through the body to the coupling means from an external source such as an oscillator-driven coil or coils, and relative proximity and orientation of the external and catheter coils is determined by monitoring amplitude and phase of the signal induced in the catheter coil.

Title
Catheter locating device
Application Number
5/797318
Publication Number
4173228
Application Date
May 16, 1977
Publication Date
November 6, 1979
Inventor
Ira N Childress
Los Angeles
CA, US
Donald H Van Steenwyk
San Marino
CA, US
Agent
Christie Parker & Hale
Assignee
Applied Medical Devices
CA, US
IPC
A61M 25/00
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