The first part of the thesis focuses on treatment of achalasia, comparing two methods: single series pneumatic dilation (PD) and peroral endoscopic myotomy (POEM). Our study of 133 patients showed that POEM was more effective than PD after five years was more effective than PD, with 81% of patients in remission, compared to 40% with PD.However, patients treated with POEM were more likely to use proton pump inhibitors.In addition, a phenomenon seen after treatment with POEM was described; a pseudodiverticulum or distal focal dilatation at the site of the myotomy, also called a 'blown-out myotomy' (BOM). This is seen in one-third of POEM patients five years after initial treatment. Patients who developed a BOMhad higher acid exposure time, more reflux complaints and symptoms of regurgitation. We concluded that the presence of a BOM could explain for certain symptoms that patients develop in the years following a myotomy.The second part of the thesis explores new treatments for gastro-esophageal reflux disease. The natural supplement benesco™ was investigated but found to be no more effective than a placebo in reducing reflux symptoms. Ziverel, a gel that forms a layer in the esophagus, offered no significant benefit for patients with persistent reflux symptoms who were taking concurrent proton pump inhibitors.A promising treatment is endoscopic anti-reflux mucosectomy (ARMS). In patients with therapy-resistant reflux symptoms, ARMS led to a significant reduction in reflux episodes and acid exposure, with no increase in swallowing problems.This technique may be an effective option for a certain group of patients who do not respond well respond to medication
