Systems and methods for treating tissue with radiofrequency energy

A method of treating gastrointestinal reflux disease comprising:

• providing a treatment device having a plurality of electrodes, the treatment device electrically connected to an external controller;
• inserting the plurality of electrodes through mucosal layer and into sphincter muscle tissue;
• applying radiofrequency energy to the plurality of electrodes to thermally treat sphincter muscle tissue below a tissue ablation threshold and create a plurality of tissue lesions along axially spaced tissue levels within the upper gastrointestinal tract in sphincter muscle tissue below the mucosal layer;
• monitoring tissue temperature throughout a procedure for treating gastrointestinal reflux disease;
• and
• regulating power in response to the monitoring step to ensure the tissue temperature at the sphincter muscle tissue below the mucosal layer at all times during operation of the treatment device to create the plurality of tissue lesions does not exceed a predetermined value which would cause one or both of tissue ablation or tissue necrosis of sphincter muscle tissue below the mucosal layer at any time during the applying of radiofrequency energy.