Patent ID: 7972335
Filing Date: 2011-07-05
Classification: A61B

Abstract:
1. A method of coaptively sealing a sidewall of biological tissue which surrounds and defines an opening in the tissue to occlude the opening, the tissue of the sidewall comprising biological fibers, the method comprising: compressing portions of the sidewall in apposition to occlude the opening; applying sufficient energy to the compressed apposed sidewall portions to cause the fibers of the compressed apposed sidewall portions to intertwine and fuse with one another to a sufficient degree to hold the apposed sidewall portions together permanently and to occlude the opening permanently; applying the energy by conducting cycles of a radio frequency (RF) current through the compressed apposed portions of the sidewall; establishing an envelope related to peak values of the cycles of the RF current conducted through the sidewall portions; mathematically differentiating the envelope to create derivative values of the peak values of the envelope; detecting a precursor fusion condition from the derivative values while applying the energy to the compressed apposite sidewall portions and before sufficient energy has been applied to cause the fibers to intertwine and fuse to the sufficient degree; and terminating the application of energy in a time-delayed relationship to the detection of the precursor fusion condition when the sufficient degree of energy has been conducted to the compressed apposed sidewall portions to intertwine and fuse the fibers to hold the apposed sidewall portions together permanently and to occlude the opening permanently.