Use of Impedance Planimetry in the Diagnosis of Gastric Sleeve Stenosis: The Establishment of New Benchmark Values

Introduction: Gastric sleeve stenosis (GSS) is an increasingly common adverse event following sleeve gastrectomy for which objective diagnostic criteria are lacking. Impedance planimetry measurements show promise in characterizing GSS, though normal and abnormal benchmark values have never been established.

Methods: This was a retrospective analysis of upper endoscopies performed with impedance planimetry for suspected GSS. A bariatric endoscopist, blind to impedance planimetry measurements, assessed gastric sleeve anatomy and graded GSS severity. Impedance planimetry of diameter and distensibility index (DI) were obtained using 3 different balloon volumes (30, 40, and 50 mL).

Results: A total of 110 upper endoscopies were included. Distribution of GSS was graded as none, mild, moderate, and severe in 19 (17%), 27 (25%), 34 (31%), and 30 (27%) procedures, respectively. In normal gastric sleeve anatomy, mean (±SD) diameter and DI measurements using consecutive balloon volumes ranged from 19.1 (±5.5) to 23.2 (±1.7) and 16.8 (±4.9) to 23.1 (±10.9), respectively. In severe GSS, mean diameter and DI measurements ranged from 10.3 (±3.0) to 16.6 (±2.1) and 7.5 (±2.4) to 7.7 (±2.4), respectively. When stratified by severity, impedance planimetry measurements of diameter and DI were significantly lower with each subsequent increase in GSS grade regardless of balloon fill volumes ( P ≤ 0.001).

Discussion: Impedance planimetry measurements provide objective assessment in the diagnosis of GSS and correlate with luminal narrowing. A diameter ≥20 mm and a DI ≥15 mm 2 /mm Hg, as measured by impedance planimetry, are predictive of normal gastric sleeve anatomy. This study provides new benchmark values for the diagnosis and severity of GSS.