S1397 Gastro-Pyloric Dysfunction in Gastroparesis

Introduction: Impedance planimetry endoscopically assesses tissue wall distensibility by pressure and cross-sectional area and assesses dynamic muscle and passive wall properties in the GI tract. Pyloric Functional Luminal Imaging Probe (pFLIP) may reveal many abnormalities in pts. with the symptoms (Sx) of gastroparesis (Gp) . We hypothesized that pts. with Gp Sx may have anatomic and physiologic abnormalities of the stomach and/or pylorus in pts. with both delayed and non-delayed gastric emptying (GE). Methods: We evaluated 69 pts. with a history of Gp who underwent a pFLIP. Pts. had baseline and follow-up measures of GI Sx by a traditional FDA compliant patient reported outcomes (TradPRO) pre and post temporary gastric electrical stimulation placement. All pts. underwent EGGs, mucosal and serosal EGs, proximal/liquid and distal/solid gastric emptying (GET) and underwent bio-electric TGES for provocative effects on proximal and distal gastric function over at least 5-days. Most pts. underwent full thickness gastric biopsies during subsequent GES placement and tissue samples were analyzed by neuromuscular stains. At a later date, pts. underwent pyloric function compliance measurements by pFLIP. Pyloric distensibility values at 40 cc volume distension were analyzed. Results were compared by t-tests and correlations using 'R' statistical software. Results: Distensibility Index (DI) 40cc was higher in the non-delayed group (5.1 vs. 5.6). CD 4 and CD 8 values were lower in the delayed GE group (0.8 and 1.0), respectively. S100 (neural fiber cells) were lower in the delayed GE group in both inner and outer muscle layers (8.0, 4.4 respectively). CD117/ Cajal cells were also lower in the delayed GE group (2.0, 1.0). Cutaneous EGG amplitude (by manual and computerized analysis) negatively correlated with gastric emptying and frequency amplitude ratio (FAR) had a positive correlation with GE. Conclusion: In this group of pts. with Gp symptoms, we found several differences in gastric microscopic anatomy and upper GI Sx responses between pts. with delayed vs. non-delayed gastric emptying. Distensibility index, at 40cc baloon volume, was often abnormal in the non-delayed GE group, which implies FLIP measurement might be useful irrespective of gastric emptying results. Using various measurement techniques, along with baseline symptoms, anatomy, and physiologic testing abnormities, may allow for more rational therapeutic plans for pts. with Gp.Table 1.: Correlations and Comparisons of FLIP with Gastric Emptying.