Peroral endoscopic myotomy (POEM) for esophageal diverticula

POEM from A to Z: current perspectives

The "third space endoscopy" or also called "submucosal endoscopy" is a reality we can transfer to our patients since 2010. Various modifications of the submucosal tunneling technique allow access to the submucosa or deeper layers of the gastrointestinal tract. In addition to peroral endoscopic myotomy for the treatment of achalasia, also called esophageal POEM, other variants have emerged that make it possible to treat different esophageal motility disorders, esophageal diverticula, subepithelial tumors of various locations, gastroparesis, reconnection of complete esophageal strictures or even thanks to exceptional endoscopists, pediatric disorders such as Hirschsprung's disease. Although some technical aspects are yet to be standardized, these procedures are becoming widespread worldwide and will likely become the standard treatment of these pathologies soon.

Laparoscopic Management of Esophageal Epiphrenic Diverticulum

A 45-year-old man who presented with progressive dysphagia of five months duration was diagnosed as a case of oesophageal epiphrenic diverticulum after endoscopic and imaging investigations. He underwent laparoscopic cardiomyotomy with Dor's fundoplication. Myotomy was done from the base of the diverticulum up to 2 cm distal to the gastroesophageal junction. Intraoperative endoscopy was done to check the adequacy of myotomy. Diverticulectomy was not done. Yet the patient had complete relief of symptoms and is well and asymptomatic after two years. Cardiomyotomy with anti-reflux procedures is effective in treating the epiphrenic diverticulum without the need for resection of the diverticulum, which also provides a better prognosis and less morbidity to the patient.

Submucosal endoscopy: the present and future

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.

Impact of modified techniques on outcomes of peroral endoscopic myotomy: A narrative review

Peroral endoscopic myotomy (POEM) is an established frontline treatment modality for achalasia cardia. Since its initial description, several modifications have been proposed to the technique of POEM. Broadly speaking, these modifications follow the basic principles of submucosal endoscopy, but incorporate variations in the POEM technique, including the difference in the orientation of myotomy (anterior or posterior), length of myotomy (short or long), and thickness of myotomy (selective circular or full thickness). Some of these modifications have been shown to reduce procedural duration without compromising the efficacy of the POEM procedure. More recently, several alterations have been reported that intend to reduce gastroesophageal reflux after POEM. These include preservation of sling fibers during posterior POEM and addition of NOTES fundoplication to the POEM procedure. Although some of the modified techniques have been compared with the conventional techniques in quality trials, randomized studies are awaited for others. The incorporation of some of these modifications will likely make POEM a technically easy and safer modality in near future. This review aims to discuss the current evidence with regard to the impact of modified techniques on the outcome of POEM.