Feasibility of Oropharyngeal pH-metry in diagnosing LPR – A single centre experience

doi:10.21203/rs.3.rs-3402148/v1

Download PDF

Article

Feasibility of Oropharyngeal pH-metry in diagnosing LPR – A single centre experience

https://doi.org/10.21203/rs.3.rs-3402148/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Purpose: Laryngopharyngeal reflux (LPR) is commonly diagnosed based on symptoms, nonspecific clinical findings, or positive response to empirical treatment. This single centre data highlights the role of Oropharyngeal pH-metry (Restech^®) in diagnosing LPR and its practicality as an alternative to Hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH).

Methods: A retrospective data of patients who underwent Oropharyngeal pH-metry (Restech^®) at Department of Otorhinolaryngology Head and Neck Surgery, Center Hospitalier de Luxembourg Eich, Luxembourg from January 2022 until November 2022. 66 patients with probable LPR symptoms with suggestive flexible scope findings were included in the study.

Results: 66 patients consist of 29 male and 37 female patients (43.94%, 56.06% respectively). The median age is 51.5 ranges from 16 to 87 years old. A positive RYAN score demonstrated in 38 (57.57%) patients while negative RYAN score demonstrated in 28 (42.42%) patients. Furthermore, 24(36.36%) patients showed severe LPR, 28(42.42%) moderate and 12(18.18%) mild, 1(1.52%) no LPR and 1(1.52%) neutral LPR. Throat discomfort and irritative cough were the main symptoms reported by the patients. Proton pump inhibitor such as Pantoprazole and Esomeprazole were the common medications given to treat LPR. The dose given is either 20mg twice daily or 40mg twice daily depending on the severity of the LPR.

Conclusion: Oropharyngeal pH-metry (Restech^®) is a feasible tool as an alternative to HEMII-pH in evaluating LPR.

Health sciences/Gastroenterology

Health sciences/Health care

Health sciences/Medical research

Laryngopharyngeal reflux (LPR) is often misdiagnosed as gastroesophageal reflux disease (GERD) thus often result in treatment failure [1]. However, in 2002, American Academy of Otolaryngology–Head and Neck Surgery has recognized LPR as an independent entity [2]. Currently, Hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH) is used to identify and characterize hypopharyngeal reflux events (HRE) and features of LPR by providing valuable information about the type and composition of reflux events occurring in the hypopharynx and helps in understanding the characteristics of LPR [3]. In comparison, Oropharyngeal pH-metry (Restech^®) has gain its popularity as a useful tool in evaluating LPR in clinical practice.[4] This 24-hours ambulatory device able to measure both liquid and aerosolised pH level in the oropharynx making it a valuable tool in determining the presence of LPR. We present a single centre data of LPR and discuss the comparison of both techniques in evaluating LPR.

The ethical approval was obtained for all protocols from local institutional review board of the Centre Hospitalier de Luxembourg Eich, Luxembourg and met national and international guidelines for research. Informed consent was obtained from all subjects and/or their legal guardians.

The data of patients who underwent 24-hours Oropharyngeal pH-metry (Restech^®) from January 2022 until November 2022 were collected retrospectively at Department of Otorhinolaryngology Head and Neck Surgery, Centre Hospitalier de Luxembourg Eich, Luxembourg. The selection criteria include all new patients referred with symptoms suggestive of LPR, patients who have been empirically treated for LPR or suggestive laparoscopic findings of LPR. Patients who are on pre-existing treatment for LPR are allowed to continue the medication during the study.

All patients underwent 24-hours Oropharyngeal pH-metry using The Restech probe (Respiratory Technology Corporation, San Diego, CA) which is a minimally invasive trans nasal catheter placed in the oropharynx. This device records patients’ input regarding clinically relevant information (meals, symptoms, sleep) with the press of a button. The probe in the oropharynx will take pH reading twice per second and the data will be analyzed using software to produce a Restech graph.

The RYAN score, which is proprietary to Restech’s DataView software was used to interpret the pH study. pH threshold of 5.5 and 5.0 are used for upright and supine positions respectively [5]. In order to account for decreased salivation while sleeping, the two are examined independently. Three components were used by the RYAN score to analyze the results. These are the percentage of time when the pH falls below a threshold, the number of episodes where the pH fell below the threshold and the length of the longest episode. In both the upright and supine positions, a typical composite RYAN Score is less than 9.41 and 6.8 respectively [6]. Other demographic data were collected from the online hospital information system and analyzed using Microsoft Excel.

A total of 66 patients were included in this data collection which consist of 29 male and 37 female patients (43.94%, 56.06% respectively). The median age is 51.5 ranges from 16 to 87 years old. Average monthly distribution of the patients were about 6 patients per month. A positive RYAN score was demonstrated in 38(57.57%) patients while negative RYAN score was demonstrated in 28(42.42%) patients. Furthermore, 24(36.36%) patients show severe LPR, 28(42.42%) moderate and 12(18.18%) mild, 1(1.52%) no LPR and 1(1.52%) neutral LPR (Fig. 1). Throat discomfort and irritative cough are the main symptoms reported by the patients (30.30% and 10.60% respectively) followed by dry cough 5(7.58%), globus sensation 5(7.58%) and choking sensation 4(6.06%).

Approximately, 51 patients (77.27%) have pre-existing treatment prior to Oropharygeal pH-metry (Restech^®) while 15 patients (22.73%) have no pre-existing treatment prior to Oropharygeal pH-metry (Restech^®).

Proton pump inhibitor such as Pantoprazole and Nexium were the medications of choice given to treat LPR with 34.85% and 27.28% respectively followed by other medications (e.g. Gaviscon and Lansoprazole) with 15.15%. On the other hand, 22.73% of patients received no treatment. The dosage frequency was documented as once a day in 25.76%, twice a day (40.91%) and trice a day (1.52%). The dose given is either 20mg twice daily or 40mg twice daily depending on the severity of the LPR.

The descriptive statistics for Ryan score upright (N < 9.41) and supine (N < 6.8) are summarized as below (Fig. 2):

The prevalence of LPR still remains unknown because there is no gold standard for the LPR diagnostic. In clinical practice, LPR is commonly diagnosed based on symptoms, nonspecific clinical findings, or positive response to empirical treatment [3]. Patients that show no symptoms relief despite treatment may require objective assessment to confirm the diagnosis of LPR. Recently, the pH study is considered as the most reliable tool to demonstrate gastric reflux into the pharynx [3].

Currently, the combined multichannel intraluminal impedance and pH monitoring (MII–pH) is a considered as standard diagnostic tool to assess gastroesophageal reflux disease (GERD). It is a catheter-based technique used to detect the movement of intraluminal bolus within oesophagus and able to detect both acid and non-acid reflux [7]. Hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH) is a used to identify and characterize hypopharyngeal reflux events (HRE) and features of LPR by providing valuable information about the type and composition of reflux events occurring in the hypopharynx and helps in further understanding the characteristics of LPR [3].

Alternatively, Oropharyngeal pH-metry (Restech®) has gained its popularity in the recent years in diagnosing and evaluating LPR. This device can measure both liquid and aerosolised pH level in the oropharynx [8]. It is 24-hours ambulatory device consist of a single probe inserted intra nasally and placed at the oropharynx just behind the uvula. Accurate placement of the probe is guided by the blinking LED light which present at the tip of the probe and does not require trained nurse or physician to perform it. In comparison, HEMII-pH involved dual probe placed at upper and lower oesophageal sphincter. It requires experienced nurse or physician to perform it and probe placement need to be confirmed by CXR, flexible scope, or pH control in the distal sensor (stomach) making it rather tedious procedure [3].

With regards to HRE, a study by Vance et al. reported that oropharyngeal pH-metry (Restech®) detected more percent time/total HREs in supine and upright positions and longer event times compared to HEMII-pH. It also correlates better with total patient symptom scores including cough, heartburn, burping, and throat clearing [9]. Furthermore, in recent systematic review involving pH study findings of 720 healthy individuals, it is observed that the 95th percentile thresholds were 0 to 10 HREs for HEMII-pH and 40 to 128 for events with pH < 6.0 on Oropharyngeal pH-metry (Restech®) respectively which conclude that Oropharyngeal pH-metry (Restech®) is more sensitive to detect HREs as compared to HEMII-pH [10].

Data analysis of oropharyngeal pH-metry (Restech®) is simple and easy to interpret. Restech graph consist of pH values over 24 hours in upright and supine positions, meals and logged symptoms and calculation of Ryan score. A positive Ryan Score indicate severe reflux and the higher values are associated with severe acid exposure in the throat [11]. Nonetheless, a negative Ryan Score does not exclude mild, moderate, alkaline, neutral LPR or no reflux. In comparison, data analysis of HEMII-pH may require experienced physician or gastroenterologist for manual analysis because the automated analysis has tendency to demonstrate excessive reflux volume [3].

For sensitivity and specificity, Kim et al reported when at least one HRE detected during the study, HEMII-pH monitoring has the sensitivity of 76.0% and specificity of 81.5% respectively [12]. A study by Hovath et al concluded that Oropharyngeal pH-metry (Restech®) has sensitivity (95% vs. 97%), accuracy (94% vs. 96%) and specificity (93% vs. 88%) in comparison to trans nasal esophagoscopy [8].

Lastly, the usefulness of pH study in relation of LPR causing otological manifestation has a potential future research topic in the world of Otorhinolaryngology. One of the limitations of nasopharyngeal pH monitoring devices available is the incapability to detect non-acid or weakly acid reflux [13], As a solution, Oropharyngeal pH-metry (Restech®) may has potential role to study the relation of LPR and common otological and sinonasal diseases by placing the probe in the nasopharynx.

Oropharyngeal pH-metry is a feasible tool to diagnose LPR in comparison to HEMII-pH. It is well-tolerated procedure with high sensitivity, specificity and accuracy in evaluating LPR.

This paper has no conflict of interest and no financial disclosure.

The ethical committee of the Hospital agreed which the study and the information was sent to the patient.

Acknowledgement:

The authors would like to thank Associate Professor Ir. Dr. Kamarul Irwan Abdul Rahim for providing data analysis for this article.

Conflict of interest: No

Data availability: The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.

Madani, A.; Sowerby, L.; Gregor, J.C.; Wong, E.; Fung, K. Detecting the other reflux disease: Laryngopharyngeal reflux is a disorder, unlike GERD, that few patients (and too few physicians) are familiar with. Misdiagnosis is common–unless you know what to look for. J. Fam. Pract. 2010, 59, 102–108.
Koufman, J.A.; Aviv, J.E.; Casiano, R.R.; Shaw, G.Y. Laryngopharyngeal Reflux: Position Statement of the Committee on Speech, Voice, and Swallowing Disorders of the American Academy of Otolaryngology-Head and Neck Surgery. YMHN 2016, 127, 32–35.
Lechien JR. Clinical Update Findings about pH-Impedance Monitoring Features in Laryngopharyngeal Reflux Patients. J Clin Med. 2022;11(11):3158. doi:10.3390/jcm11113158
Respiratory Technology Corporation, Restech, 2019, The Dx–pH Measurement System, Pharyngeal pH Testing Explained. Restech. https://www.restech.com/pharyngeal-ph-testing-how-it-works-and-how-its-different/
(Ayazi S, Lipham JC, Hagen JA, et al. A New Technique for Measurement of Pharyngeal pH: Normal Values and Discriminating pH Threshold. J Gastrointest Surg. 2009;13(8):1422–9.)
Laryngopharyngeal-reflux-and-the-ryan-score. Restech Reflux Solutions. Retrieved July 19, 2023, from https://www.restech.com/laryngopharyngeal-reflux-and-the-ryan-score/)
Yano F, Omura N, Tsuboi K, et al. Standard values of 24-h multichannel intraluminal impedance–pH monitoring for the Japanese. Esophagus. 2017;14(1):91–96. doi:10.1007/s10388-016-0549-1
Horvath L, Hagmann P, Burri E, Kraft M. Evaluation of Oropharyngeal pH-Monitoring in the Assessment of Laryngopharyngeal Reflux. J Clin Med. 2021;10(11):2409. doi: 10.3390/jcm10112409. PMID: 34072412; PMCID: PMC8198919.
Vance D., Park J., Alnouri G., Turner R.R., Daggumati S., Ferster A.P.O., Ahmad A., Lyons K., Ross J., Russell K., et al. Diagnosing Laryngopharyngeal Reflux: A Comparison between 24-hour pH-Impedance Testing and Pharyngeal Probe (Restech) Testing, with Introduction of the Sataloff Score. J. Voice. 2021:S0892-1997(21)00136-3. doi: 10.1016/j.jvoice.2021.04.002.
Lechien J.R., Chan W.W., Akst L.M., Hoppo T., Jobe B.A., Chiesa-Estomba C.M., Muls V., Bobin F., Saussez S., Carroll T.L., et al. Normative Ambulatory Reflux Monitoring Metrics for Laryngopharyngeal Reflux: A Systematic Review of 720 Healthy Individuals. Otolaryngol. Head Neck Surg. 2022;166:1945998211029831. doi: 10.1177/01945998211029831.
Ayazi S., Lipham J.C., Hagen J.A., Tang A.L., Zehetner J., Leers J.M., Oezcelik A., Abate E., Banki F., DeMeester S.R., et al. A New Technique for Measurement of Pharyngeal pH: Normal Values and Discriminating pH Threshold. J. Gastrointest. Surg. 2009;13:1422–1429. doi: 10.1007/s11605-009-0915-6.
Kim SI, Jeong SJ, Kwon OE, et al. Pharyngeal reflux episodes in patients with suspected laryngopharyngeal reflux versus healthy subjects: a prospective cohort study. Eur Arch Otorhinolaryngol. 2021;278(9):3387–3392. doi:10.1007/s00405-021-06865-8
Wong I.W., Omari T.I., Myers J.C., Rees G., Nair S.B., Jamieson G.G., Wormald P.J. Nasopharyngeal pH monitoring in chronic sinusitis patients using a novel four channel probe. Laryngoscope. 2004;114:1582–1585. doi: 10.1097/00005537-200409000-00015.

No competing interests reported.

Download PDF

Version 1

posted

You are reading this latest preprint version

Feasibility of Oropharyngeal pH-metry in diagnosing LPR – A single centre experience

Status:

Version 1

Abstract

Figures

Introduction

Methods

Results

Discussion

Conclusions

Declarations

References

Additional Declarations

Status:

Version 1