Zenker's diverticulum advancing beyond the tunnel. Authors are listed here and here are our disclosures. Following introduction of the flexible endoscopic cricopharyngeal myotomy, rapid advancements in endoscopy have led to the Zenker's per-oral endoscopic myotomy and associated modifications, allowing treatment of a broader spectrum of patients. We will summarize the available endoscopic methods for treating Zenker's diverticulum and related conditions. During traditional endoscopic cricopharyngeal myotomy, a nasogastric tube can be inserted to delineate the true esophageal lumen. In this procedure, a concurrent septotomy and myotomy of the cricopharyngeal muscle is performed. The aim is for a complete myotomy, however this can be difficult to gauge endoscopically and an incomplete myotomy is felt to be a large contributor to high reported relapse rates of up to 30%. Once the septum is transected, through the scope clips can be placed at the apex to prevent perforation. In a Z-POEM, a submucosal injection followed by mucosal incision is performed one to two centimeters proximal to the septum. Submucosal tunneling is then performed until the septum is exposed, allowing a complete myotomy. As an incomplete myotomy is felt to be a large contributor to recurrence following a standard septotomy, this theoretically reduces the risk of recurrence. Here, a submucosal injection is performed 1.5 centimeters proximal to the center septum to create a mucosal bleb. We use a premix solution of indigo carmine and normal saline. A mucosal incision is then made along the axis of the septum. The use of a clear cap helps to separate tissue and improves both visualization and working space. It aids entrance to the submucosal space where tunneling is performed until the septum is reached. Injection of the premix solution via a pump maintains visualization of the mucosal planes. Bleeding can quickly impair visualization and should be treated promptly. Here, Cole graspers are used to grab the culprit vessel and a gentle pull towards the scope while applying soft coagulation successfully stops the bleed. Dissection is then continued until the septum is completely exposed on both sides. A complete myotomy is then performed transacting through the cricopharyngeal muscle and extending a few centimeters into esophageal muscle. Re-look demonstrates full thickness myotomy. Finally, the mucosal incision site is closed with through the scope clips. Clips are placed sequentially in close approximation until the entire defect is sealed. In a modified z-poem, submucosal injection followed by mucosal incision is performed directly over the septum. Submucosal dissection is then performed on either side for exposure prior to myotomy. In contrast to achalasia, visualization of the Zenker's septum negates the need for proximal tunneling. Here, a submucosal injection is performed directly over the septum until a mucosal bleb is created. Mucosal incision is then made along the axis of the septum. Once the submucosal space is entered, the septum is visualized and dissection is performed on either side followed by full thickness myotomy through the cricopharyngeus and into esophageal muscle. Notably, working space during mucosal closure is larger, reducing technical difficulty and improving visualization of closure adequacy. This theoretically reduces the risk of leak and is now the preferred technique at our institution. We prefer short stem clips due to the proximal location as this decreases the foreign body sensation for patients. Importantly, during standard septotomy or z-poem, diverticulectomy is not performed. Furthermore, as the mucosa is left intact during z-poem, a large mucosal flap can contribute to residual symptoms. We propose the addition of a mucosotomy in large Senker's diverticulum. Shown here is the endoscopic appearance following completion of myotomy as part of a modified z-poem. The large residual mucosal flap is stabilized with placement of through the scope clips. Here we placed one clip at either end of the mucosal incision. The mucosa in between the two clips is then transected, allowing a wider communication between the diverticulum and esophageal lumen. This is carefully performed sequentially until the base of the diverticulum is reached, as appreciated here. Complete closure is then obtained by sequential clip placement across the entire mucosal defect. Recurrence of Senker's after treatment is not uncommon and patients are increasingly presenting after prior surgical or endoscopic therapy. In this case, a surgical staple is seen, indicative of prior treatment. Submucosal injection results in minimal lift. Following mucosal incision, the submucosal plane was not readily identifiable, despite repeated injection of the pre-mixed normal saline and indigo carmine solution. A decision is made to commence standard septotomy. After the initial incision, fibrotic tissue can be clearly seen. Septotomy is continued sequentially until submucosal tissue is eventually visualized. Injection of the pre-mixed solution into this tissue is then able to delineate the submucosal plane, allowing the completion of a submucosal tunnel. The benefit of this procedure over standard septotomy is that tunneling can be performed at the crucial point, the base of the diverticulum, to allow direct visualization and confirmation of a complete myotomy, thereby again theoretically reducing the risk of recurrence. We will now briefly mention the use of these techniques in the management of other upper esophageal disorders. In a cricopharyngeal bar, there is no diverticulum or septum, however a similar technique can still be adopted. In this patient with a prominent cricopharyngeal bar, submucosal injection is performed proximal to the cricopharyngeus, followed by a mucosal incision. Again, the submucosal space is entered and tunneling allows clear identification of the thickened cricopharyngeus. Full thickness myotomy can then be performed from the cricopharyngeus extending to the end of the tunnel. Finally, the mucosal incision is closed with clips. The Z-bond procedure can also be modified for treatment of other esophageal diverticuli or even a combination of pathologies. Here, a prominent cricopharyngeus is noted, causing resistance to passage of the scope. Distal to this, a diverticulum is seen. Mucosal bleb and mucosal incision is created proximal to the cricopharyngeus. Submucosal tunneling is then performed from this level and extending beyond the diverticular septum to normal esophageal muscle. Once the muscular septum is exposed, myotomy is performed and extended to the end of the tunnel. Then, the scope is pulled back until the cricopharyngeus is identified and a complete cricopharyngeal myotomy is performed. Relog demonstrates adequate treatment of the tight cricopharyngeus and diverticular septum. Static mucosal closure is then performed with clips. In conclusion, multiple endoscopic treatment modalities for Zenkis dimeticulum are available, which can also be modified to treat other upper esophageal conditions.

endoscopic methods

Zenker's diverticulum

cricopharyngeal myotomy

Z-POEM technique

modified Z-POEM technique