Mark A. Solinski, MD Feinberg School of Medicine, Northwestern University, Chicago, IL Introduction: Per-oral endoscopic myotomy (POEM) is a highly effective treatment for achalasia. Functional Luminal Imaging Probe (FLIP) offers real-time measurement of esophagogastric junction (EGJ) opening parameters, allowing for an objective method to assess myotomy adequacy. a measure of how easily the esophagus can expand and contract, calculated by dividing the area of the esophagus by the pressure it's under during a controlled distension. The aim of this study was to assess if the change in pre-POEM to post-POEM distensibility index (DI) was more predictive of symptomatic outcome compared to an absolute threshold. Methods: Thirty-one patients with type I and type II achalasia who received POEM between November 2022 and August 2024 were included. Based on previous literature, an EGJ distensibility index (DI) 2.8mm2/ mmHg was considered a complete myotomy. Clinical success of POEM was defined as Eckardt score (ES) < 4. Concordance was defined by symptom improvement and a normal post-POEM DI, or no symptom improvement and an abnormal post-POEM DI. Discordance was defined by symptom improvement and an abnormal post-POEM DI, or no symptom improvement and a normal post-POEM DI. Results: Thirty-One patients with achalasia who underwent POEM had pre-POEM and post-POEM DI data. A proposed cut-off using the change in pre-POEM to post-POEM DI change of 0.8mm2/mmHg (Delta DI) was evaluated.Most of the discordance was driven by patients with symptomatic improvement, but abnormal DI. The accuracy of delta DI versus an absolute cutoff for assessing treatment response was evaluated using the receiver operating curve analysis. The difference in percentage of concordance between patients with pre-POEM and post-POEM DI using the absolute cut-off and the proposed delta-DI was significant (p=0.014). There was a 68% concordance with the absolute DI cut-off vs. 90% concordance with the delta-DI cut-off. Discussion: DI is a useful diagnostic tool in patients with achalasia. However, discrepant symptomatic and DI outcomes have been difficult to reconcile post-POEM. Using a traditional cut-off of an absolute post-POEM DI of 2.8 may result in more discordance than using the delta-DI described in this study. This study highlights the importance of updates regarding DI as a metric of procedural success and the need to redefine its parameters in this setting.
Disclosures: Mark Solinski indicated no relevant financial relationships.
Mark A. Solinski, MD, 62, Evaluation of Distensibility Index to Determine Procedural Success After Peroral Endoscopic Myotomy (POEM) for Non-Spastic Achalasia, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.
