Evaluating Intraoperative Impedance Planimetry Findings Using a 16 cm Catheter in Patients Undergoing Peroral Endoscopic Myotomy ( POEM )

Introduction Functional lumen imaging probe (FLIP) planimetry performed during peroral endoscopic myotomy (POEM) evaluates esophagogastric junction (EGJ) metrics. The 16 cm FLIP catheter allows for topographical assessment of the esophageal body, and previous intraoperative studies have only utilized the 8 cm catheter or combined data from both catheters. Our aim was to characterize the utility of the 16 cm catheter during POEM with respect to intraoperative tailoring of the myotomy length and intermediate outcomes after POEM. Methods We conducted a retrospective review of procedural and follow‐up information of consecutive patients who underwent POEM with an intraoperative 16 cm catheter between January 2020 and September 2023. Results In 100 patients with intraoperative FLIP, the mean myotomy length was 8.2 cm. A tailored short myotomy (≤ 4 cm) using FLIP was performed in 10% of cases with comparable outcomes in LES obstruction and GERD metrics compared to > 4 cm myotomy length. On the basis of topographical FLIP findings, the myotomy was extended to capture spastic body features in 32% of cases including Type 2 achalasia (5), epiphrenic diverticulum (3) and prior myotomy (10). In intervention‐naive patients, 70.5% achieved clinical success (Eckardt ≤ 3) at median follow‐up of 30.9 months (IQR 6.5–40.9 months) with improvement in LES obstruction and GERD metrics among the intermediate follow‐up cohort. An intraoperative post‐myotomy EGJ diameter of ≥ 16 mm was associated with a lower rate of repeat intervention (2 vs. 5 patients, p = 0.038) and not associated with increased reflux outcomes. Conclusion Intraoperative FLIP using the 16 cm catheter during POEM enables a tailored myotomy guided by both EGJ metrics and topographical assessment.