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Laryngeal sensory testing in the assessment of patients with laryngopharyngeal reflux

Published online by Cambridge University Press:  26 October 2009

O T Dale ,
O Alhamarneh ,
K Young  and
S Mohan
O T Dale*
Affiliation:
Derby Voice Clinic, Department of ENT Surgery, Derbyshire Royal Infirmary, Derby, UK
O Alhamarneh
Affiliation:
Derby Voice Clinic, Department of ENT Surgery, Derbyshire Royal Infirmary, Derby, UK
K Young
Affiliation:
Derby Voice Clinic, Department of ENT Surgery, Derbyshire Royal Infirmary, Derby, UK
S Mohan
Affiliation:
Derby Voice Clinic, Department of ENT Surgery, Derbyshire Royal Infirmary, Derby, UK
*
Address for correspondence: Mr Oliver T Dale, Department of ENT Surgery, Musgrove Park Hospital, Taunton TA1 5DA, UK. Fax: 01332347141 E-mail: otdale@doctors.net.uk
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Abstract

Laryngopharyngeal reflux is commonly encountered in the ENT out-patient setting. It leads to impaired sensory capacity of the laryngeal mucosa. The sensory integrity of the laryngopharynx can be evaluated through endoscopic administration of pulsed air, which stimulates the laryngeal adductor reflex. The pressure of air needed to elicit this reflex indicates the degree of sensory impairment. Such laryngeal sensory testing gives a quantifiable means of assessment in patients with laryngopharyngeal reflux, and can be used to measure the response to treatment. Laryngeal sensory testing is safe and well tolerated by patients.

Keywords

DysphoniaLaryngeal EdemaLaryngeal MucosaHoarseness

Information

Type
Short Communication
Information
The Journal of Laryngology & Otology , Volume 124 , Issue 3 , March 2010 , pp. 330 - 332
Copyright
Copyright © JLO (1984) Limited 2009

Introduction

Laryngopharyngeal reflux (LPR) is common: between 4 and 10 per cent of patients presenting to ENT out-patient clinics have reflux-related symptoms.Reference Koufman1 The condition commonly presents with symptoms of hoarseness, persistent throat-clearing, dysphagia, cough and sore throat, which are often intermittent and recurring.Reference Koufman, Aviv, Casiano and Shaw2 In addition, there are several long term sequelae associated with LPR, including subglottic stenosis, laryngospasm, paradoxical vocal fold movement and laryngeal carcinoma.Reference Koufman, Aviv, Casiano and Shaw2, Reference Maronian, Azadeh, Waugh and Hillel3

Given the functional impairment and possible serious complications of LPR, accurate diagnosis and effective management is important. Several diagnostic tools are available to the clinician. The ‘gold standard’ is thought to be 24 hour pH monitoring using a double lumen (oesophageal and pharyngeal) probe.Reference Postma4 However, this is seldom conducted in routine clinical practice as it is invasive and time-consuming. Other diagnostic tools include the reflux symptom index (a validated patient questionnaire) and the reflux finding score (based on pathological features of LPR seen on direct visualisation of the larynx and supraglottis). In the UK, these tools are commonly used in conjunction to diagnose LPR.

The treatment of LPR remains controversial. Many centres treat suspected LPR empirically with proton pump inhibitors (PPIs). However, this approach offers the clinician no quantifiable means of disease surveillance. In addition, a recent systematic review has indicated that treatment of LPR with PPIs confers no benefit over placebo.Reference Karkos and Wilson5

Laryngeal sensory testing was first described by Aviv et al. in 1993 as a component of flexible endoscopic evaluation of swallowing with sensory testing.Reference Aviv, Martin, Keen, Debell and Blitzer6 The former procedure tests the integrity of the brainstem-mediated laryngeal adductor reflex, using administration of pulsed air to the laryngopharynx.Reference Aviv, Martin, Kim, Sacco, Thomson and Diamond7 Stimulation of the laryngeal mucosa in this way results in adduction of the vocal folds in the normal individual. Laryngeal sensory testing was originally used as a diagnostic adjunct in the assessment of swallowing disorders, but has more recently been applied to patients suffering from LPR. Patients with LPR have been shown to have sensory deficits of the posterior larynx, which lead to an impaired laryngeal adductor reflex on stimulation of the laryngeal mucosa.Reference Aviv, Liu, Parides, Kaplan and Close8

The use of laryngeal sensory testing in patients with LPR enables the clinician to quantify the degree of laryngeal sensory impairment, which has important implications for both the diagnosis and surveillance of the disease.

Laryngeal sensory testing

Materials

The following materials were used: a flexible nasolaryngoscope (25–30 cm length, 3.6 mm diameter; Olympus P4; Olympus, Southend-on-Sea, United Kingdom); disposable endoscope sheaths with air delivery port (Figure 1) (Vision Sciences, MedTronic, New York, United States); a videolaryngoscopy system with video-recording capacity (Xion; Sheffmed, Sheffield, United Kingdom); and an air pulse sensory stimulator (Figure 1) (Vision Sciences).

Fig. 1

Flexible nasolaryngoscope attached to air pulse sensory stimulator.

Technique

Laryngeal sensory testing is carried out using a specially designed sensory stimulator (Figure 1). The device is calibrated to endoscopically administer an air pulse of varying pressure (2–10 mmHg) to the arytenoid mucosa, in an attempt to elicit the laryngeal adductor reflex. Each pulsed administration of air lasts 50 milliseconds. If no response to the air pulse is achieved at any pressure, continuous air stimulation can be used. The air pulse sensory stimulator must be calibrated every time it is used.

The air pulse threshold is initially set to 10 mmHg. The tip of the endoscope is brought to within 2 mm of the arytenoid mucosa and the air pulse delivered. As the air is delivered, it is possible to see the resulting indentation on the mucosa. Once the pulse has been delivered, the endoscope must be slightly withdrawn to preserve the endoscopist's field of vision as the laryngeal adductor reflex occurs. If the laryngeal adductor reflex is absent on pulse stimulation at maximum strength, continuous air flow is used. If this fails to elicit adduction of the vocal folds, the patient is assumed to have an absent laryngeal adductor reflex. Laryngeal sensory testing is performed on both the left and right arytenoid mucosa to determine a sensory threshold for each.

If the laryngeal adductor reflex is elicited at an air pressure of 10 mmHg, sequentially lower air pressures (at intervals of 2 mmHg) are used to determine the sensory threshold for each side. When the laryngeal adductor reflex becomes absent during this process, the air pressure is increased in smaller increments until a precise sensory threshold for each side of the laryngeal mucosal is determined. The laryngeal sensory thresholds for deficits of varying severity are shown in Table I.

Table I

Sensory capacity of laryngopharynx as determined by laryngeal sensory testing

If no effect is seen at 10 mmHg air pressure with continuous flow, the laryngeal adductor reflex is assumed to be absent. LAR air pressure = air pressure at which laryngeal adductor reflex is elicited

Discussion

Loss of sensory discrimination in the laryngopharynx as a result of LPR has been well documented.Reference Aviv, Liu, Parides, Kaplan and Close8 Despite this, laryngeal sensory testing is not commonly used in the assessment of this condition in the UK. The authors have found that laryngeal sensory testing provides a useful adjunct to the assessment and monitoring of patients with LPR, when used in combination with the reflux finding score and the reflux symptom index. This finding is supported by work conducted by Aviv et al., who demonstrated that the laryngopharyngeal sensory deficits of patients with LPR improve with PPI therapy, and that both were correlated with an improvement in patient symptoms and laryngopharyngeal oedema.Reference Aviv, Liu, Parides, Kaplan and Close8 In addition to providing a quantitative assessment of laryngeal sensitivity, laryngeal sensory testing has been shown to be reproducible, with good intra-observer reliability, thus allowing the clinician to monitor the response to treatment.Reference Cunningham, Halum, Butler and Postma9, Reference Aviv, Kim, Thomson, Sunshine, Kaplan and Close10

Laryngeal sensory testing has been shown to be a safe procedure, with no significant adverse side effects. In a series of 1340 patients, epistaxis occurred in only one, and there were no instances of airway compromise.Reference Aviv, Murry, Zschommler, Cohen and Gartner11 In another study of 500 consecutive examinations, the most frequently occurring side effect of laryngeal sensory testing was mild discomfort, which occurred in 71 per cent of patients.Reference Aviv, Kaplan, Thomson, Spitzer, Diamond and Close12 In the same study, 99 per cent of the patients stated they would undergo the procedure again if clinically indicated.

Conclusion

Given the prevalence of LPR and the workload burden this places on ENT departments, a quick, easy, cost-effective assessment tool is desirable. Laryngeal sensory testing fulfils these criteria and is well tolerated by patients, making it a useful adjunct to the assessment and monitoring of patients with LPR.

References

1Koufman, JA. The otolaryngologic manifestations of gastroesophageal reflux disease (GERD): a clinical investigation of 225 patients using ambulatory 24-hour pH monitoring and an experimental investigation of the role of acid and pepsin in the development of laryngeal injury. Laryngoscope 1991;101:1–78CrossRefGoogle Scholar
2Koufman, JA, Aviv, JE, Casiano, RR, Shaw, GY. Laryngopharyngeal reflux: position statement of the committee on speech, voice, and swallowing disorders of the American Academy of Otolaryngology-Head and Neck Surgery. Otolaryngol Head Neck Surg 2002;127:32–5CrossRefGoogle Scholar
3Maronian, NC, Azadeh, H, Waugh, P, Hillel, A. Association of laryngopharyngeal reflux disease and subglottic stenosis. Ann Otol Rhinol Laryngol 2001;110:606–12CrossRefGoogle ScholarPubMed
4Postma, GN. Ambulatory pH monitoring methodology. Ann Otol Rhinol Laryngol Suppl 2000 Oct;184:10–4CrossRefGoogle ScholarPubMed
5Karkos, PD, Wilson, JA. Empiric treatment of laryngopharyngeal reflux with proton pump inhibitors: a systematic review. Laryngoscope 2006;116:144–8CrossRefGoogle ScholarPubMed
6Aviv, JE, Martin, JH, Keen, MS, Debell, M, Blitzer, A. Air pulse quantification of supraglottic and pharyngeal sensation: a new technique. Ann Otol Rhinol Laryngol 1993;102:777–80CrossRefGoogle ScholarPubMed
7Aviv, JE, Martin, JH, Kim, T, Sacco, RL, Thomson, JE, Diamond, B et al. Laryngopharyngeal sensory discrimination testing and the laryngeal adductor reflex. Ann Otol Rhinol Laryngol 1999;108:725–30Google ScholarPubMed
8Aviv, JE, Liu, H, Parides, M, Kaplan, ST, Close, LG. Laryngopharyngeal sensory deficits in patients with laryngopharyngeal reflux and dysphagia. Ann Otol Rhinol Laryngol 2000;109:1000–6CrossRefGoogle ScholarPubMed
9Cunningham, JJ, Halum, SL, Butler, SG, Postma, GN. Intraobserver and interobserver reliability in laryngopharyngeal sensory discrimination thresholds: a pilot study. Ann Otol Rhinol Laryngol 2007;116:582–8CrossRefGoogle ScholarPubMed
10Aviv, JE, Kim, T, Thomson, JE, Sunshine, S, Kaplan, S, Close, LG. Fiberoptic endoscopic evaluation of swallowing with sensory testing (FEESST) in healthy controls. Dysphagia 1998;13:87–92CrossRefGoogle ScholarPubMed
11Aviv, JE, Murry, T, Zschommler, A, Cohen, M, Gartner, C. Flexible endoscopic evaluation of swallowing with sensory testing: patient characteristics and analysis of safety in 1,340 consecutive examinations. Ann Otol Rhinol Laryngol 2005;114:173–6CrossRefGoogle Scholar
12Aviv, JE, Kaplan, ST, Thomson, JE, Spitzer, J, Diamond, B, Close, LG. The safety of flexible endoscopic evaluation of swallowing with sensory testing (FEESST): an analysis of 500 consecutive evaluations. Dysphagia 2000;15:39–44CrossRefGoogle ScholarPubMed
Figure 0

Fig. 1 Flexible nasolaryngoscope attached to air pulse sensory stimulator.

Figure 1

Table I Sensory capacity of laryngopharynx as determined by laryngeal sensory testing