Methods for performing coagulation necrosis of biological tissue are
provided. The methods include configuring electrode arrays to provide
balanced energy density in target tissue volumes using two or more pair
of electrodes. The electrode array configuration includes at least one of
irregular spacing between one or more pairs of electrodes and one or more
electrode diameters. The methods further include deploying each electrode
of an array at a selected depth in the target tissue volume in accordance
with the configuration. Energy is then delivered to the target tissue
volume using power sources coupled to the electrodes. The methods control
power delivery in response to at least one of elapsed time of delivery,
temperatures of the target tissue volume, and impedance levels in the
target tissue volume to provide balanced or uniform energy throughout the
target tissue volume. The methods generate planes of coagulated tissue.