Navigational tunnel technique for gastric peroral endoscopic pyloromyotomy: getting straight to the point (pylorus)

Background and Aims Gastric peroral endoscopic pyloromyotomy (G-POEM) is emerging as a treatment option for patients with gastroparesis. The most technically difficult part of the procedure is creating a submucosal tunnel in the gastric antrum, which can be directionally challenging. We describe a novel navigational tunneling method that guides submucosal dissection in the direction of the pylorus and helps to identify the pyloric landmarks. Methods Consecutive patients from September to December 2020 who underwent G-POEM for symptomatic gastroparesis were included. All cases were confirmed by prolonged gastric emptying study. The navigational tunnel technique was performed as follows: (1) mucosal cautery markings were made to outline the tunnel starting 3 to 4 cm proximal to the pylorus, (2) submucosal injection was done at the level of the pylorus and extended backward to the incision point, and (3) submucosal dissection was carried out after the prior submucosal injection straight to the pylorus. Results Six patients with gastroparesis underwent G-POEM with the navigational tunneling technique. The average time for submucosal injection was 2 minutes and 42 seconds, and the average tunnel time was 15 minutes and 36 seconds. There were no adverse events. All patients reported significant improvement (50%-85%) in symptoms. Conclusions This novel navigational tunneling technique appears to guide and facilitate G-POEM by providing a visual path for submucosal dissection straight to the pylorus. It may increase efficiency, decreasing the need to repeatedly exit the tunnel to check direction and preventing nonproductive wandering. It may also help identify the pyloric ring within the tunnel.