Peroral Endoscopic Myotomy with EndoFLIP and Double-Endoscope: Novel Techniques for Achalasia in Pediatric Population.

BACKGROUND: Experience of peroral endoscopic myotomy (POEM) for treatment of achalasia in pediatric population is limited with varying techniques in different centers. The accurate extent of submucosal tunneling into the gastric cardia and the adequacy of myotomy are the important determining factors to success of POEM. A majority of studies in pediatric population have described using submucosal dye injection for assessing the adequacy of myotomy, however, this is a rather crude and inaccurate method. We herein describe the first case of pediatric achalasia managed with POEM incorporated with novel combined techniques using EndoFLIP® (Endoluminal Functional Lumen Imaging Probe) and double endoscope.

METHODS: Esophagogastric junction (EGJ) was identified with a gastroscope. Before POEM, EndoFLIP showed EGJ distensibility index of 1.7 mm2 /mmHg. Submucosal tunnel was created from the mucosal entry site at midesophagus down and ∼3 cm beyond the EGJ. Anterior myotomy cutting the circular muscle layer while preserving the longitudinal muscle was performed for 8 cm. Double-endoscope technique was used to confirm the adequacy of myotomy by inserting a smaller endoscope through nostril into stomach and observing the transillumination of the first endoscope at the end of submucosal tunnel. After POEM, repeat EndoFLIP measurements revealed increased distensibility index to 6.0 mm2 /mmHg. Endoscopic examination at the end of the procedure showed widely patent EGJ.

RESULTS: Eckardt symptoms score improved from 9 to 0. At 7 month after POEM, esophagoscopy showed widely open EGJ with no esophagitis, and high-resolution esophageal manometry revealed normalized lower esophageal sphincter pressure and resting tone.

CONCLUSIONS: We introduced the intraoperative use of EndoFLIP system that allows real-time assessment of EGJ distensibility and immediate treatment effect evaluation. Incorporation of double-endoscope POEM was also first described in our pediatric patient for ensuring complete gastric myotomy. From our experiences, POEM for achalasia in pediatric population appears to have encouraging results similar to adult patients.