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Updated: Apr 19, 2026

Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Normal esophageal pressure topography metrics for data derived from the Sandhill-Unisensor high-resolution manometry
G C do Carmo1, J Jafari, D Sifrim
1Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
Background:
Normal values of the esophageal motor function parameters for high-resolution manometry (HRM-EPT) adopted by the Chicago classification were established using the proprietary system of Given Imaging. It is conceivable that normal values of a system do not apply to data from others. Most studies using HRM were based on supine swallows, whereas deglutition occurs mostly in the upright position. We wished to establish normal values for HRM-EPT parameters obtained with the Sandhill's HRM-EPT system and compare the results in supine and sitting positions.
Methods:
Sixty-nine healthy volunteers, 38 females, median age 27 years, were included in this study. All underwent supine HRM, and 34 of them underwent sitting HRM, with at least 10 single 5-mL swallows for analysis obtained in each position.
Key Results:
The normal range (5-95th percentiles) for the following parameters was calculated: distal contractile integral (DCI), 606-4998 mmHg·s·cm; contractile front velocity (CFV), 2.0-6.5 cm/s; distal latency (DL), 5.1-8.8 s; intrabolus pressure (IBP), 1.9-17.6 mmHg; upper esophageal sphincter (UES) pressure, 45.2-186.9 mmHg; esophagogastric junction (EGJ) length, 1.8-4 cm; EGJ resting pressure, 8.1-61.6 mmHg, and integrated relaxation pressure (IRP) 2.5-23.5 mmHg. Normal values of EGJ resting pressure, IRP, DCI, and IBP but not CFV, DL, and UES resting pressure were significantly lower in the sitting posture.
Conclusions & Inferences:
Studies performed with Sandhill's HRM-EPT system should use its own specific normal data. Normal values should be established for different study.
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