Validation of Pharyngeal Acid Reflux Episodes Using Hypopharyngeal Multichannel Intraluminal Impedance-pH

Yen-Yang Chen; Chen-Chi Wang; Ying-Cheng Lin; John Y Kao; Chun-Yi Chuang; Yung-An Tsou; Ja-Chih Fu; Sheng-Shun Yang; Chi-Sen Chang; Han-Chung Lien

doi:10.5056/jnm22047

Validation of Pharyngeal Acid Reflux Episodes Using Hypopharyngeal Multichannel Intraluminal Impedance-pH

J Neurogastroenterol Motil. 2023 Jan 30;29(1):49-57. doi: 10.5056/jnm22047.

Authors

Yen-Yang Chen¹, Chen-Chi Wang^{2

3

4}, Ying-Cheng Lin¹, John Y Kao⁵, Chun-Yi Chuang^{6

7}, Yung-An Tsou⁸, Ja-Chih Fu⁹, Sheng-Shun Yang^{1

7

10}, Chi-Sen Chang^{1

7}, Han-Chung Lien^{1

3

11}

Affiliations

¹ Division of Gastroenterology, Taichung Veterans General Hospital, Taichung, Taiwan.
² Department of Otolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan.
³ School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
⁴ School of Speech Language Pathology and Audiology, Chung Shan Medical University, Taichung, Taiwan.
⁵ Department of Internal Medicine, Division of Gastroenterology, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA.
⁶ Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan.
⁷ School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
⁸ Department of Otolaryngology-Head and Neck Surgery, China Medical University Hospital, Taichung, Taiwan.
⁹ Computer Aided Measurement and Diagnostic Systems Laboratory, Department of Industrial Engineering and Management, National Yunlin University of Science and Technology, Yunlin, Taiwan.
¹⁰ Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan.
¹¹ Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.

Abstract

Background/aims: Hypopharyngeal multichannel intraluminal impedance-pH (HMII-pH) technology incorporating 2 trans-upper esophageal sphincter impedance channels has been developed to detect pharyngeal reflux. We used the HMII-pH technique to validate the candidate pharyngeal acid reflux (PAR) episodes based on the dual-pH tracings and determined the interobserver reproducibility.

Methods: We conducted a cross-sectional study in tertiary centers in Taiwan. Ninety patients with suspected laryngopharyngeal reflux and 28 healthy volunteers underwent HMII-pH test when off acid suppressants. Candidate PAR episodes were characterized by pharyngeal pH drops of at least 2 units and reaching a nadir pH of 5 within 30 seconds during esophageal acidification. Two experts manually independently identified candidate PAR episodes based on the dual-pH tracings. By reviewing the HMII-pH tracings, HMII-pH-proven PAR episodes were subsequently confirmed. The consensus reviews of HMII-pH-proven PAR episodes were considered to be the reference standard diagnosis. The interobserver reproducibility was assessed.

Results: A total of 105 candidate PAR episodes were identified. Among them 84 (80.0%; 95% CI, 71.0-87.0%) were HMII-pH-proven PAR episodes (82 in 16 patients and 2 in 1 healthy subject). Patients tended to have more HMII-pH-proven PAR episodes than healthy controls (median and percentile values [25th, 75th, and 95th percentiles]: 0 [0, 0, 3] vs 0 [0, 0, 0], P = 0.067). The concordance rate in diagnosing HMII-pH-proven PAR episodes between 2 independent observers was 92.2%.

Conclusion: Our preliminary data showed that 80.0% (71.0-87.0%) of the proposed candidate PAR episodes were HMII-pH-proven PAR episodes, among which the interobserver reproducibility was good.

Keywords: Acids; Esophagus; Gastroesophageal reflux.