04905698 is referenced by 263 patents and cites 7 patents.

A method and apparatus (10) for determining accurately the location of the tip (14) of a catheter (16) inside biological tissue is disclosed including a locator (34) having a coil (38) wound axially on a core (36) and a detector (12) in the form of a coil (28) wound on a core (24) removably positionable within catheter (16) adjacent the tip (14). A controller (20) generates AC current to coil (38) to produce an electromagnetic field and compares it with the output voltage developed in coil ( b 28) when the locator (34) comes within close physical proximity to detecetor (12). Locator (34) includes an amber LED indicator (42) which is energized when the locator (34) is behind the detector (12) and the monitored output voltage is in phase with the generated alternating current and includes a red LED indicator (44) which is energized when the locator (34) is beyond the detector (12) and the monitored output voltage is 180.degree. out of phase with the generated alternating current. The controller (20) includes a beeper (48) which provides an audible indicator when energization changes between the indicators (42, 44).

Title
Method and apparatus for catheter location determination
Application Number
7/243689
Publication Number
4905698
Application Date
September 13, 1988
Publication Date
March 6, 1990
Inventor
Gary R Whipple
S. Attleboro
MA, US
Alan R Shapiro
Sharon
MA, US
Donald A Kay
Sharon
MA, US
Michael C Ferragamo
N. Dighton
MA, US
Clair L Strohl Jr
Norfolk
MA, US
Agent
Peterson Wicks Nemer & Kamrath
Assignee
Pharmacia Deltec
MN, US
IPC
A61B 6/12
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