Duodenal ablation with improved depth and consistency of ablation

A method for treating at least one of excess weight, obesity, eating disorders, metabolic syndrome, dyslipidemia, diabetes, polycystic ovarian disease, fatty liver disease, non-alcoholic fatty liver disease, or non-alcoholic steatohepatitis disease by ablating duodenal tissue using a vapor ablation system, wherein the vapor ablation system comprises a catheter having at least one positioning element configured to expand outward from the catheter, wherein, upon expansion, the at least one positioning element defines a portion of a first treatment zone, wherein ports are positioned on the catheter and are configured to direct ablative fluid from within the catheter out toward said first treatment zone, and wherein the vapor ablation system further comprises a controller having at least one processor in electrical communication with the catheter, the method comprising:

• positioning the catheter in a patient's duodenum;
• causing the at least one positioning element to expand and define the portion of the first treatment zone;
• activating the controller, wherein, upon activation, the controller delivers a first fluid to the catheter and causes the catheter to heat the first fluid to form a first ablative fluid such that the first ablative fluid leaves the catheter through the ports over a first period of time, wherein the first ablative fluid delivered over the first period constitutes a first dose and wherein the first dose comprises less energy than required to achieve effective ablation of tissue in the first treatment zone;
• after the first period of time, waiting a second period of time to permit a structural change in a mucosa layer or submucosa layer of the duodenum;
• and
• after said second period of time, activating the controller, wherein, upon activation, the controller is configured to deliver a second fluid to the catheter and cause the catheter to heat the second fluid to a second ablative fluid such that the second ablative fluid leaves the catheter through the ports over a third period of time, wherein the second ablative fluid delivered over the third period constitutes a second dose and wherein the second dose comprises at least one of a) less energy than required to achieve effective ablation of tissue in the first treatment zone, b) sufficient energy required to achieve effective ablation of tissue in the first treatment zone, or c) more energy than required to achieve effective ablation of tissue in the first treatment zone.