Patent · US Expired

Impedance feedback monitor for electrosurgical instrument

US5558671A · kind A · utility

2,596Cited by
31References
11Claims
0Family size

Inventor

Key dates

Filing dateSep 23, 1994
Grant dateSep 24, 1996
Priority date
Expiry dateSep 23, 2014

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B2090/032
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

An impedance monitoring device is provided for monitoring the electrical impedance of tissue as it is treated with electrosurgical energy. Based on a predicted model of tissue impedance and a number of initial impedance readings, the impedance at which tissue treatment is completed is predicted. More particularly, a minimum impedance level is measured and a function of the minimum impedance is used to determine impedance at which coagulation is completed. A control device is provided for bringing the output of the generator within an optimum range based on a system load curve. In one embodiment the impedance monitoring device is used in conjunction with a bipolar electrosurgical instrument. Preferably, the instrument comprises electrically opposite electrodes located on one or more tissue engaging surfaces for engaging tissue to be treated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.