High Resolution Manometry Has Low Sensitivity and High Specificity for Detecting Hiatal Hernia

Introduction: Hiatal hernias (HH) are frequently diagnosed during upper endoscopy or barium radiography. With the introduction of high resolution manometry (HRM), hiatal hernias can be identified based on finding 2 separate high pressure zones on high resolution topography. The aim of this study is to compare HRM and endoscopic identification of HH. An earlier study done in our institution in 2005 by Agrawal et.al comparing conventional manometry (CM) to endoscopy to identify HH showed that CM had low sensitivity (20%), but high specificity (99%) in identifying HH compared to endoscopy. Methods: A retrospective review was performed of 600 patients who had HRM performed in our laboratory between January 2013 and February 2014. We identified 160 patients (107 females, mean age 54.5 years) who had both HRM and upper endoscopy. The manometric studies were reviewed looking for characteristic double high-pressure zone on high resolution topography separated by 1 cm or more. The endoscopic reports were reviewed for independent identification of HH. Results: Of the 160 patients who had both HRM and EGD, 31 (19%) had HH identified by HRM compared to 29 (18%) by EGD. 12/31 of the manometrically identified HH were also seen on endoscopy. Compared to endoscopy (gold standard), HRM had a sensitivity of 41.4% and a specificity of 87.2% for detecting HH. Conclusion: HRM has low sensitivity and relatively high specificity in identifying HH. Further studies analyzing HRM using better objective criteria need to be identified to more accurately detect HH. Related to our earlier study of CM and EGD, HRM showed higher sensitivity, but lower specificity compared to CM to identify HH. Disclosure - Dr. Donald Castell is a consultant for Sandhill Scientific.