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Investigating the utility of EndoFLIP™ as a screening tool for pathologic reflux EndoFLIP™ as a screening tool for
John W Keyloun1,2, Andrew Mertz1,3, Bonnie C Carney4
1Johns Hopkins Sibley Memorial Hospital, Washington, DC, USA.
Background:
The Endoluminal Functional Lumen Imaging Probe (EndoFLIP™) is increasingly utilized in the diagnostic evaluation of gastroesophageal reflux disease (GERD). At our Center, EndoFLIP™ is routinely performed before Bravo™ pH monitoring during preoperative esophagogastroduodenoscopy to exclude major motility disorders in patients being considered for antireflux surgery. According to Lyon Consensus 2.0, the presence of Los Angeles (LA) grade B or higher esophagitis is diagnostic for GERD, obviating the need for pH testing. In select cases, bypassing pH monitoring reduces costs, improves workflow efficiency, and expedites symptom management. This study aimed to evaluate whether EndoFLIP™ measurements independently predict Bravo™ pH positivity and to assess the diagnostic accuracy of distensibility index (DI) thresholds.
Methods:
We conducted a single-center retrospective review of adults with native anatomy who underwent 96-h Bravo™ pH monitoring and concomitant EndoFLIP™ at index EGD between October 2022 and August 2024. Patients with positive (Bravo +) and negative (Bravo-) studies were compared. Diagnostic accuracy of DI values (DI50, DI60, DI70) was assessed using receiver operating characteristic (ROC) curves, with area under the curve (AUC) and 95% confidence intervals (CI).
Results:
A total of 171 patients were included (64 Bravo + , 107 Bravo-). LA grade B esophagitis was more common among Bravo + patients (7.8% vs. 0%, p = 0.007). Median DI60 was significantly higher in Bravo + patients (4.0 vs. 3.4 mm2/mmHg, p = 0.016). ROC analysis showed DI50 and DI60 yielded good discrimination for Bravo + (AUC 0.67 and 0.65) with high specificity (94%). In males, DI50 and DI60 both performed well (AUC 0.69), whereas in females, DI70 provided the strongest diagnostic value (AUC 0.69, 95% CI 0.49-0.89). The cut-off points for DI50, DI60, and DI70 in the overall sample were 4.2 (95% CI: 3.8-4.6), 4.7 (95% CI: 4.3-5.1), and 3.8 (95% CI: 3.5-4.3), respectively.
Conclusion:
DI60 values are significantly associated with Bravo + testing. Across the overall cohort and male sex, DI50 and DI60 demonstrated a strong diagnostic performance, while DI70 showed better performance in females.
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