Abstract: In part, the disclosure relates to a method of cosmetic tissue treatment. The method includes disposing a treatment applicator comprising an electrode array comprising a plurality of needles on a portion of tissue such that a region of the electrode array contacts the portion of tissue, wherein each needle is an electrode in electrical communication with a control system; applying a pulse of radio frequency (RF) energy to the portion of tissue through the electrode array; measuring impedance of electrode array over time; detecting a drop in the measured impedance while electrode array is in contact with the portion of tissue; and upon detection of the reduction in impedance by a threshold value, terminating application of the pulse of RF energy after a treatment time period.