Ryan J Campagna, MD, Dustin A Carlson, MD, Eric S Hungness, MD, Amy L Holmstrom, MD, John E Pandolfino, MD, Nathaniel J Soper, MD, Ezra N Teitelbaum, MD, MEd. Northwestern University Feinberg School of Medicine
Introduction: The functional lumen imaging probe (FLIP) is a novel measurement catheter that can evaluate esophagogastric junction (EGJ) distensibility and esophageal peristalsis in real time using impedance planimetry technology. FLIP measurements performed during diagnostic endoscopy have been shown to accurately discriminate between healthy controls and patients with achalasia, based on EGJ distensibility and distinct motility patterns termed repetitive antegrade contractions (RACs) and repetitive retrograde contractions (RRCs). We sought to evaluate real time motility changes in patients undergoing surgical myotomy for achalasia.
Methods: FLIP measurements using stepwise volumetric distention protocol were performed at three time points during laparoscopic Heller myotomy and POEM: 1) During preoperative outpatient endoscopy, 2) Intraoperatively following induction of general anesthesia, and 3) Intraoperatively after myotomy completion. Distensibility (defined as the minimum cross-sectional area at the EGJ divided by pressure) was measured and the presence or absence of any contractility, RACs, and/or RRCs.
Results: FLIP measurements were performed in 18 patients. Median distensibility was similar between the preoperative and initial operative measurements (1.16 vs 1.03 mm2/mmHg, p=NS). There was a significant increase in distensibility following surgical myotomy, with final distensibilities in the previously defined range of healthy controls (1.03 to 4.23 mm2/mmHg, p<0.05). Intraoperative motility patterns varied between achalasia subtypes. Contractility was seen in less than 5% of all assessments in patients with achalasia types I and II, whereas type III patients demonstrated contractility in 89% of assessments, with 72% exhibiting RRCs, 50% RACs, and 33% exhibiting both patterns. There was a reduction in the frequency of RACs (83% to 17%) and RRCs (83% to 67%) between pre and post-myotomy intraoperative measurements.
Conclusions: This first report of real time intraoperative measurement of esophageal motility using FLIP demonstrates the feasibility of such assessments during surgical myotomy for achalasia. Patients with type I and II achalasia exhibited rare intraoperative contractility, while the presence of motility was the norm in those with type III. Patients with type III achalasia demonstrated a reduction in repetitive contraction motility patterns as a result of the myotomy.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 95134
Program Number: S044
Presentation Session: Foregut II – Physiology
Presentation Type: Podium