Laryngopharyngeal reflux remains a diagnostic challenge due to the lack of a definitive diagnostic tool. Esophageal multichannel intraluminal impedance (MII) pH monitoring has been proven reliable for detecting gastric reflux. This study aims to evaluate the association between clinical scores and MII/pH monitoring according to the Lyon Consensus 2.0. Patients with laryngo-pharyngeal symptoms (LPS) who had a reflux symptom index (RSI) ≥13 or reflux finding score (RFS) ≥7 underwent MII/pH monitoring. The findings were analyzed in comparison with clinical scores. A total of 100 patients meeting the inclusion criteria were recruited for this study. MII/pH monitoring revealed a median acid exposure time (AET) of 1.9% (interquartile range [IQR] = 0.2, 4.9), with 22% of patients recording an AET above 6%. The median number of reflux episodes was 29.5 episodes per day (IQR = 19.0, 43.8), with 7% experiencing more than 80 episodes per day. Gas reflux was identified as the most prevalent type. Based on the Lyon Consensus 2.0, 25 patients exhibited conclusive pathological reflux, while 75 patients showed no conclusive evidence of pathological reflux. No significant differences were found in RSI and RFS between these groups. Only gas reflux episodes showed a significant correlation with RSI (r = 0.255, P = 0.011). RSI and RFS among patients with LPS showed no statistically significant differences in identifying pathological reflux or no conclusive evidence of pathological reflux. This finding suggests that the pathophysiology underlying LPS may not be solely attributable to reflux.

Diagnosing laryngopharyngeal reflux (LPR) is challenging due to overlapping symptoms. While proton pump inhibitors (PPIs) are commonly prescribed, reliable predictors of their responsiveness are unclear. Reflux monitoring technologies like dual potential of hydrogen (pH) sensors and multichannel intraluminal impedance-pH (MII-pH) could improve diagnosis. Research suggests that a composite pH parameter, defined by ≥ 2 pharyngeal acid reflux (PAR) episodes and/or excessive esophageal acid reflux (EAR), predicts PPI efficacy. The criteria for PAR episodes, a pharyngeal pH drop of ≥ 2 units to < 5 within 30 seconds during esophageal acidification, showed strong interobserver reliability. We hypothesized that PAR episodes alone might also predict PPI responsiveness.

To investigate whether PAR episodes alone predict a positive response to PPI therapy.

Patients suspected of having LPR were prospectively recruited from otolaryngologic clinics in three Taiwanese tertiary centers. They underwent a 24-hour esophagopharyngeal pH test using either 3-pH-sensor or hypopharyngeal MII-pH catheters while off medication, followed by a 12-week esomeprazole course (40 mg twice daily). Participants were categorized into four groups based on pH results: PAR alone, EAR alone, both pH (+), and both pH (-). The primary outcome was a ≥ 50% reduction in primary laryngeal symptoms, with observers blinded to group assignments.

A total of 522 patients (mean age 52.3 ± 12.8 years, 54% male) were recruited. Of these, 190 (mean age 51.5 ± 12.4 years, 61% male) completed the treatment, and 89 (47%) responded to PPI therapy. Response rates were highest in the PAR alone group (73%, n = 11), followed by EAR alone (59%, n = 68), both pH (+) (56%, n = 18), and both pH (-) (33%, n = 93). Multivariate analysis adjusting for age, sex, body mass index, and endoscopic esophagitis showed that participants with PAR alone, EAR alone, and both pH (+) were 7.4-fold (P = 0.008), 4.2-fold (P = 0.0002), and 3.4-fold (P = 0.03) more likely to respond to PPI therapy, respectively, compared to the both pH (-) group. Secondary analyses using the definition of ≥ 1 PAR episode were less robust.

In the absence of proven hypopharyngeal predictors, this post-hoc analysis found that baseline ≥ 2 PAR episodes alone are linked to PPI responsiveness, suggesting the importance of hypopharyngeal reflux monitoring.

The pepsin test is an emerging non-invasive diagnostic approach for laryngopharyngeal reflux (LPR). The aim of this study was to investigate the diagnostic value of multiple salivary pepsin tests for detecting LPR.

Patients with suspected LPR and asymptomatic individuals were consecutively recruited from January 2020 to November 2022. Patients benefited from hypopharyngeal-esophageal impedance-pH monitoring (HEMII-pH) and fasting and bedtime saliva collections to measure oral pepsin. The sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated considering fasting, bedtime, and the highest values of the pepsin tests at ≥16, ≥36, ≥45, and ≥100 ng/mL cutoffs.

The pepsin test was adequately performed in 147 LPR patients and 32 controls. The pepsin tests were 81.6%, 74.8%, and 61.5% sensitive at cutoffs of ≥16, ≥45, and ≥100 ng/mL, respectively. The PPVs were 93.0%, 94.0%, and 94.8%, respectively. The highest specificity (81.8%) was found for the fasting pepsin test at a cutoff of 100 ng/mL. The highest sensitivity (81.6%) was found by considering the highest measured pepsin test at the ≥16 ng/mL threshold. The measurement of fasting saliva pepsin was associated with the highest sensitivity and specificity value. At ≥16 ng/mL, 27 patients had negative findings, indicating that 18.4% (27/147) of the true positive cases were missed by considering the highest pepsin test. The receiver operating characteristic curve reported that a cutoff of 21.5 was 76.9% sensitive and 62.5% specific, while the PPV and NPV were 91.1% and 38.2%, respectively.

The consideration of the highest concentration of the fasting and bedtime saliva pepsin collections at a cutoff of 21.5 was associated with the best detection rate and sensitivity of the pepsin tests.

Laryngopharyngeal reflux (LPR) is a variant of gastroesophageal reflux disease (GERD) in which gastric refluxate irritates the lining of the aerodigestive tract and causes troublesome airway symptoms or complications. LPR is a prevalent disease that creates a significant socioeconomic burden due to its negative impact on quality of life, tremendous medical expense, and possible cancer risk. Although treatment modalities are similar between LPR and GERD, the diagnosis of LPR is more challenging than GERD due to its non-specific symptoms/signs. Due to the lack of pathognomonic features of endoscopy, mounting evidence focused on physiological diagnostic testing. Two decades ago, a dual pH probe was considered the gold standard for detecting pharyngeal acidic reflux episodes. Despite an association with LPR, the dual pH was unable to predict the treatment response in clinical practice, presumably due to frequently encountered artifacts. Currently, hypopharygneal multichannel intraluminal impedance-pH catheters incorporating two trans-upper esophageal sphincter impedance sensors enable to differentiate pharyngeal refluxes from swallows. The validation of pharyngeal acid reflux episodes that are relevant to anti-reflux treatment is, therefore, crucial. Given no diagnostic gold standard of LPR, this review article aimed to discuss the evolution of objective diagnostic testing and its predictive role of treatment response.

Purpose: The diagnosis of laryngopharyngeal reflux (LPR) is commonly based on non-specific symptoms and findings and a positive response to an empirical therapeutic trial. The therapeutic response is, however, unpredictable, and many patients need pH-impedance monitoring to confirm the diagnosis. Methods: A review of the recent literature was conducted in PubMED, Scopus, and Embase about the pH-study features of LPR patients. A summary of last evidence was proposed. Results: The awareness of otolaryngologists about indications and interpretation of pH-impedance monitoring is low. The hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH) is the most reliable examination determining the type and composition of hypopharyngeal reflux events (HRE) and the LPR features. The use of HEMII-pH is important to confirm the diagnosis in selected patients because non-specificity of symptoms and findings. There are no international consensus guidelines for the LPR diagnosis at the HEMII-pH. However, most studies supported the occurrence of >1 acid/weakly acid/nonacid HRE as diagnostic threshold. HREs are more frequently gaseous, weakly/nonacid compared with reflux events of gastroesophageal reflux. HREs occurred as daytime and upright, which does not support the value of double proton pump inhibitors or bedtime alginate. Oropharyngeal pH-monitoring is another approach reporting different sensitivity and specificity outcomes from HEMII-pH. The use of Ryan score for the LPR diagnosis at the oropharyngeal pH monitoring may be controversial regarding the low consideration of alkaline HREs. Conclusions: The awareness of otolaryngologists about HEMII-pH indication, features, and interpretation is an important issue regarding the high prevalence of LPR in outpatients consulting in otolaryngology. The HEMII-pH findings may indicate a more personalized treatment considering type and occurrence time of HREs.

Laryngopharyngeal reflux (LPR) is frustrating, as symptoms are nonspecific and diagnosis is often unclear. Two main approaches to diagnosis are empiric treatment trials and objective reflux testing. Initial empiric trial of Proton pump inhibitors (PPI) twice daily for 2-3 months is convenient, but risks overtreatment and delayed diagnosis if patient complaints are not from LPR. Dietary modifications, H2-antagonists, alginates, and fundoplication are other possible LPR treatments. If objective diagnosis is desired or patients' symptoms are refractory to empiric treatment, pH testing with/without impedance should be considered. Additionally, evaluation for non-reflux etiologies of complaints should be performed, including laryngoscopy or videostroboscopy.

Laryngopharyngeal reflux (LPR) is caused by the reflux of gastric contents beyond the esophagus into the larynx and pharynx. However, upper esophageal sphincter (UES) motility and proximal esophagus reflux parameters are poorly studied. This study aims to explore the characteristics of UES motility and reflux parameter among LPR patients.

Patients with laryngopharyngeal symptoms only (L), patients with laryngopharyngeal symptoms and typical esophageal symptoms (L + E), patients with typical esophageal symptoms only (E), and healthy controls (H) were retrospectively included. Physiological profiles were studied and compared among groups using both high-resolution manometry and pH-impedance monitoring, including UES basal pressure, residual pressure, relaxation duration time, recovery time, the time to nadir pressure, UES length, proximal contractile integral, and proximal mean nocturnal baseline impedance (MNBI). Patients' symptom outcomes were also analyzed.

A total of 242 patients were included. Proximal MNBI was significantly lower in patients with both laryngopharyngeal and esophageal symptoms (17 cm above low esophageal sphincter [LES]: L vs L + E vs E vs H = 3689.7 vs 2500.0 vs 3073.0 vs 3996.0; 15 cm above LES: L vs L + E vs E vs H = 3155.9 vs 2553.4 vs 3198.9 vs 2985.2; P < 0.001). Patients responded to proton pump inhibitor treatment also had lower proximal MNBI than those who did not (17 cm above LES: 1834.0 vs 3500.0; 15 cm above LES: 1946.5 vs 3432.6; P < 0.001).

Decreased proximal MNBI can not only identify LPR patients but also predict patients' symptom outcomes.

Patients with isolated laryngopharyngeal reflux symptoms (LPRS) defined as those without concomitant typical reflux symptoms (CTRS) are clinically challenging to manage due to unclear pathophysiology. We investigated esophageal physiology in patients with isolated LPRS and their response to proton-pump inhibitors (PPI) therapy.

This is a multi-center observational study conducted in referral hospitals in Taiwan. Patients with predominant LPRS, but without common non-reflux causes, underwent esophageal manometry, 24-hr ambulatory esophagopharyngeal pH testing, and Bernstein test, followed by a 12-week esomeprazole 40 mg twice-daily treatment. Participants with pathological reflux were divided into the isolated LPRS group (ie, LPRS without CTRS, n = 40) and the CTRS group (ie, LPRS with CTRS, n = 66). Participants without pathological reflux or esophagitis (n = 132) served as the nonreflux controls.

The PPI-responsiveness was similar between the isolated LPRS group and CTRS group (63% vs 57%, P = .8), but lower in the nonreflux controls (32%, P = .005). Despite similar distal esophageal acid exposure time (P = .7) when compared to those with CTRS, the isolated LPRS group had a lower prevalence of both positive Bernstein test (P = .001) and ineffective esophageal motility disorder (P = .03), and fewer pharyngeal acid reflux episodes (P < .0001).

Our findings indicate similar distal esophageal acid exposure and PPI-responsiveness between LPRS patients with and without CTRS. The lack of CTRS in the isolated LPRS group is likely due to esophageal acid hyposensitivity and fewer pharyngeal acid reflux episodes, thus implicating distinct pathophysiology of isolated LPRS from those with CTRS.

Laryngopharyngeal reflux (LPR) accounts for 4-10% of outpatient visits. The standard domestic LPR diagnostic tools are the reflux finding score (RFS) and reflux symptom index (RSI). Narrow band imaging (NBI) can identify previously unknown characteristic microvessel features. Our aim was to explore the role of NBI in LPR diagnosis.

We recruited 56 LPR outpatients and 41 symptom-negative controls. All individuals received RSI and RFS scores and underwent 24-hour multichannel intraluminal impedance-PH (MII-pH) monitoring and endoscopic NBI before and after treatment. The positivity rates in the study and control groups, before and after treatment, and using NBI and the conventional method were evaluated.

Fifty-one LPR and six control patients had sparse light brownish dots or tufted light brownish dots in the postcricoid region. The RSI and RFS positivity rates were 31.3% and 87.1%, respectively. NBI is as effective as the RFS (P < 0.05), and has poor consistency with the RSI (P < 0.05). Fifty-three LPR patients underwent posttreatment laryngoscopy. The positivity rate decreased to 17.0% (P < 0.05).

NBI has good value for LPR diagnosis.

To review the current literature about the epidemiology, clinical presentation, diagnosis, and treatment of laryngopharyngeal reflux (LPR).

PubMed, Cochrane Library, and Scopus.

A comprehensive review of the literature on LPR epidemiology, clinical presentation, diagnosis, and treatment was conducted. Using the PRISMA statement, 3 authors selected relevant publications to provide a critical analysis of the literature.

The important heterogeneity across studies in LPR diagnosis continues to make it difficult to summarize a single body of thought. Controversies persist concerning epidemiology, clinical presentation, diagnosis, and treatment. No recent epidemiologic study exists regarding prevalence and incidence with the use of objective diagnostic tools. There is no survey that evaluates the prevalence of symptoms and signs on a large number of patients with confirmed LPR. Regarding diagnosis, an increasing number of authors used multichannel intraluminal impedance-pH monitoring, although there is no consensus regarding standardization of the diagnostic criteria. The efficiency of proton pump inhibitor (PPI) therapy remains poorly demonstrated and misevaluated by incomplete clinical tools that do not take into consideration many symptoms and extralaryngeal findings. Despite the recent advances in knowledge about nonacid LPR, treatment protocols based on PPIs do not seem to have evolved.

The development of multichannel intraluminal impedance-pH monitoring and pepsin and bile salt detection should be considered for the establishment of a multiparameter diagnostic approach. LPR treatment should evolve to a more personalized regimen, including diet, PPIs, alginate, and magaldrate according to individual patient characteristics. Multicenter international studies with a standardized protocol could improve scientific knowledge about LPR.

Supraesophageal reflux of gastric contents can contribute to perennial nasopharyngitis, cough, and asthma. However, effective treatment strategies for supraesophageal reflux disease (SERD) remain inadequately defined.

The purpose of this study is to assess the prevalence and timing of SERD and to investigate the efficacy of head-of-bed elevation in its treatment.

A retrospective chart review of patients seen at Scripps Clinic Division of Allergy, Asthma and Immunology was performed who had undergone overnight nasopharyngeal pH monitoring with a commercially available nasopharyngeal pH-monitoring device, Dx-pH Measurement System from Restech, San Diego, Calif. Subjects with reflux were classified based on the position of reflux as either supine only, upright only, or both supine and upright. In a subset of subjects with supine-only reflux, pH monitoring was compared before and after elevating the head of bed 6 inches.

Adequate nasopharyngeal pH-monitoring data were obtained for 235 patients. Reflux was detected in 113 (48%) patients. The pattern of reflux observed was 62 (55%) supine only, 4 (4%) upright only, and 47 (42%) upright and supine. Sequential overnight nasopharyngeal pH monitoring before and after head-of-bed elevation was obtained in 13 individuals with supine-only reflux. Ten subjects demonstrated significant improvement, 8 of whom demonstrated complete resolution of supine reflux with 6 inches of head-of-bed elevation.

This study provides new evidence that SERD frequently occurs in the supine position and that 6 inches of head-of-bed elevation is effective in reducing supine SERD.

To investigate the laryngopharyngeal reflux (LPR) episodes and pH values in patients with suspected obstructive sleep apnoea (OSA) using the Dx-pH oropharyngeal probe.

Prospective cohort study.

Tertiary medical centre.

Forty patients with complaint of snoring or suspected OSA were prospectively enrolled to receive full nocturnal polysomnography (PSG). The patients were divided into 2 groups: a simple snorers group if the Respiratory Disturbance Index (RDI) was < 5 and an OSA group if the RDI was ≥ 5.

The patients simultaneously received Dx-pH oropharyngeal probe monitoring for 12 h from about 6 pm to 6 am of the next day. The number of LPR events was recorded if the nadir of rapid pH drops was below pH 5.0 and 5.5. The difference of LPR events between the two groups and the difference of LPR events between awake and sleep periods in each group were analysed, respectively.

There were 18 (45%) patients diagnosed as OSA with a mean RDI of 28.7, and 22 patients (55%) diagnosed as simple snorers. Between 2 groups, there were no significant differences in the LPR events and pH values during the awake period, sleep period or overall recording period. Comparison of the LPR events and minimum pH values between the awake period and the sleep period revealed there were no significant differences in either group.

Using the new sensitive Dx-pH oropharyngeal probe with PSG, we found that OSA does not correlate with a higher incidence of LPR episodes.

Cough persisting beyond 8 weeks (ie, chronic cough) is one of the most common reasons for an outpatient visit. A protracted cough can negatively affect one's quality of life by causing anxiety, physical discomfort, social isolation, and personal embarrassment. Herein, the anatomy and physiology of the cough reflex are reviewed. Upper airway cough syndrome, asthma, eosinophilic bronchitis, and gastroesophageal reflux disease account for most chronic cough after excluding smoking, angiotensin-converting enzyme inhibitor use, and chronic bronchitis. Many patients have more than one reason for chronic cough. Treating the underlying cause(s) resolves cough in most instances. There are some coughs that seem refractory despite an extensive work-up. The possibility of a hypersensitive cough reflex response has been proposed to explain these cases. Several clinical algorithms to evaluate chronic cough are presented.

We sought to ascertain the normal pH values in the aerosolized environment of the nasopharynx in healthy subjects and utilize a novel pH probe that allows measuring acidity in a nonliquid environment.

Between November 2009 and February 2011, healthy volunteers without a history of reflux or eustachian tube dysfunction were enrolled in the prospective study. A total of 20 subjects had a Dx-pH Measurement System Probe (Respiratory Technology Corp) placed near the torus tubarius. The pH probe records the pH throughout the 24-hour study. A pH below 5.5 while the subject was upright or below 5.0 while the subject was supine was used as a criterion to determine a reflux event. Recording was stopped during meals.

For normal individuals with no history of reflux or eustachian tube dysfunction, the pH values obtained from the nasopharynx ranged from 6.10 to 7.92. The average pH was 7.03 (SD, 0.67). Eight subjects (40%) had at least 1 reflux event during the 24-hour pH study.

By utilizing a novel self-condensing pH probe, we were able to perform a 24-hour pH study in the nasopharynx of 20 healthy individuals. In our study, the average pH for individuals without symptomatic reflux or eustachian tube dysfunction was 7.03. Interestingly, 8 control subjects had at least 1 episode of pH below 5.5 while awake or below 5.0 while asleep, which was considered to be a reflux event in our study.

Identifying and treating patients with extra-esophageal symptoms is a challenge. When the patient is unable to control his symptoms with pharmacological therapy alone, anti-reflux surgery may be indicated. This study aims to evaluate the outcomes of total fundoplication in the resolution of extra-esophageal manifestations and verify changes in 24-h MII-pH monitoring before and after surgery. From October 2005 to October 2010, patients who reported respiratory symptoms, possibly related to GERD, have been sent to our Institute. All patients were practiced ambulatory 24-h MII-pH before and after surgery. Thirty-five patients selected for the antireflux surgery have undergone all the same surgical procedures. Data were collected prospectively at 6 and 12 months after laparoscopic fundoplication. After laparoscopic fundoplication, the total percentage of exposure time with esophageal pH < 4, and both in upright and supine position was very low. A statistically significant difference (p < 0.05) was found in the number of detected refluxes at MII and detected refluxes at MII 15-cm segment in pre and post-operative period. Symptom relief was obtained in all patients. Laparoscopic fundoplication is a safe and effective procedure to protect from refractory GERD and extra-esophageal symptoms, when evaluated with a thorough pre-operative selection.

Little is known about the difference between patients of chronic laryngitis with and without troublesome reflux symptoms. The aim of this study was to compare the clinical characteristics and response to acid suppression between patients of chronic laryngitis with and without troublesome reflux symptoms.

Consecutive patients with chronic laryngitis were enrolled. The frequency and severity of reflux and laryngeal symptoms were scored. All the patients underwent laryngoscopy, esophagogastroduodenoscopy and 24-h multichannel intraluminal impedance and pH monitoring before receiving rabeprazole 10 mg b.i.d. for 3 months. Mild typical reflux symptoms (heartburn or regurgitation) occurring ≥ 2 days/week or moderate/severe symptoms occurring ≥ 1 day/week were defined as troublesome reflux symptoms.

Compared to patients without troublesome reflux symptoms, those with troublesome reflux symptoms were older and had more episodes of acid and liquid gastroesophageal reflux (GER) and acid and weakly acidic laryngopharyngeal reflux (LPR). They also had higher percentages of both bolus exposure time and acid exposure time of GER and LPR. Patients with troublesome reflux symptoms responded to acid suppression more often at 12 weeks (67.3% vs 20.9%, P < 0.001) and more rapidly (40.8% vs 14.0%, 3 weeks after the start of acid suppression; P = 0.004) compared to those without.

Difference in reflux profile of GER and LPR between patients with and without troublesome reflux symptoms could partly explain the discrepancy of response to acid suppression among patients with chronic laryngitis. Acid suppression therapy may provide limited therapeutic benefits to patients of chronic laryngitis without troublesome reflux symptoms.

Gastroesophageal reflux disease (GERD) is common in patients with respiratory disorders and interstitial lung fibrosis from diverse disease processes. However, a cause-effect relationship has not been well demonstrated. It is hypothesized that there might be more than a coincidental association between GERD and interstitial lung damage. There is still confusion about the diagnostic steps necessary to confirm the presence of GERD, and about the role of effective control of GERD in the natural history of these respiratory disorders.

To determine the prevalence of GERD in patients with respiratory disorders and lung involvement; the sensitivity of symptoms in the diagnosis of GERD; and the role of esophageal function tests (manometry and 24- hour pH monitoring) in the diagnosis and treatment of these patients.

Prospective study based on a database of 44 patients (29 females) with respiratory disorders: 16 patients had idiopathic pulmonary fibrosis, 11 patients had systemic sclerosis associated interstitial lung disease, 2 patients had polymyositis associated interstitial lung disease, 2 patients had Sjögren associated interstitial lung disease, 2 patients had rheumatoid artrithis associated interstitial lung disease, 1 patient had undifferentiated connective tissue diseases associated interstitial lung disease and 10 patients had sarcoidosis. The average forced vital capacity (% predicted) was 64.3%. All patients had esophageal function tests.

Thirty patients (68%) had pathologic reflux (average DeMeester score: 45, normal <14.7). The average number of reflux episodes recorded 20 cm above the lower esophageal sphincter was 24. Sensitivity and specificity of heartburn were 70% and 57%, of regurgitation 43% and 57%, and of dysphagia 33% and 64%. Twelve patients with GERD underwent a laparoscopic fundoplication which was tailored to the manometric profile: three patients in which peristalsis was normal had a total fundoplication (360°) and nine patients in which the peristalsis was absent had a partial anterior fundoplication (180°).

The results of our study show that: (a) abnormal reflux was present in about 2/3 of patients with respiratory disorders (idiophatic pulmonary fibrosis, connective tissue disorders and sarcoidosis), and it extended to the upper esophagus in most patients; (b) the sensitivity and specificity of reflux symptoms was very low; and (c) esophageal function tests were essential to establish the diagnosis of abnormal reflux, to characterize the esophageal function and guide therapy. Long term follow-up will be necessary to determine if control of reflux alters the natural history of these respiratory disorders.

Extraesophageal (EE) symptoms such as cough and throat clearing are common in patients referred for reflux testing, but are less commonly associated with gastroesophageal reflux disease (GERD). Patients with reflux associated EE symptoms often lack typical GERD symptoms of heartburn and regurgitation. Our aim was to compare the frequency of proximal esophageal reflux between esophageal (typical) symptoms and EE (atypical) symptoms. Combined multichannel intraluminal impedance-pH (MII-pH) tracings were blinded by an investigator so that symptom markers were relabeled with a number without disclosure of symptom type. We selected 40 patients with at least five reflux-related symptom events for one of four symptoms (heartburn, regurgitation, cough, or throat clearing). A blinded investigator analyzed all 200 reflux episodes, reporting the proximal esophageal extent of the reflux for all symptoms. The percentage of symptom-related reflux extending proximally to 17 cm above the LES was similar among all four symptom types. At least 50% of all symptoms were associated with proximal esophageal reflux to 17 cm, with regurgitation having the highest frequency at 60%. Our data indicate that EE symptoms are not more frequently associated with proximal esophageal reflux than typical esophageal symptoms.

To define the normative data of gastroesophageal reflux (GER) and laryngopharyngeal reflux (LPR) in healthy Chinese volunteers.

Healthy volunteers without gastrointestinal and throat disease and symptoms were enrolled and underwent 24-hour impedance-pH monitoring.

A total of 37 healthy volunteers completed all the tests (female 54.1%; age 38.0±15.2 years). Of 1862 GER, 49.6% were mixed, 40.9% were liquid and 9.5% were gas. More than half (54.9%) were acid. The median and 95th percentile numbers of GER were 52 and 71, respectively. The number of LPR was eight, of which two were mixed and the others were liquid. Only one episode of reflux was classified as acid LPR. The median and 95th percentile numbers of LPR were 0 and 2, respectively. More liquid reflux were associated with LPR (P=0.02). Age had no influence on GER and LPR reflux profiles.

Few LPR occurred in healthy Chinese volunteers and they were rarely acid when they reached the larynx. LPR was mostly associated with liquid reflux.

Gastro-oesophageal reflux disease (GERD) has been associated with reflux laryngitis.

To investigate the risk factors and the predictors of pharyngeal acid reflux (PAR) in Taiwanese patients with suspected reflux laryngitis.

With referral from ENT physicians, 104 patients with symptoms and signs suggestive of reflux laryngitis completed a validated symptom questionnaire, an upper endoscopy exam and ambulatory 24-h pH tests with three sensors located at the hypopharynx, proximal and distal oesophagus. Patients with one or more episodes of PAR were considered abnormal.

Pharyngeal acid reflux was identified in 17% (18/104) of patients. In multivariate logistic regression analysis, PAR was independently associated with classical reflux symptoms [adjusted odds ratio (aOR) = 3.5, 95% confidence interval (CI): 1.0-12.8], hiatus hernia (aOR = 6.7, 95% CI: 1.5-30.2) and overweight (aOR = 3.4, 95% CI: 1.0-11.0). In predicting PAR, classical reflux symptoms had a sensitivity of 78% and hiatus hernia had a specificity of 95%. With all three factors, the positive predictive value for PAR was 80%. Classical reflux symptoms included heartburn, chest pain, dyspepsia and acid regurgitation.

Classical reflux symptoms, hiatus hernia and overweight are independent risk factors that may predict pharyngeal acid reflux in patients with suspected reflux laryngitis.

Pharyngeal pH monitoring is the standard diagnostic approach for laryngopharyngeal reflux (LPR). However, the normal values for Asian populations are still unknown. We evaluated the results of ambulatory 24-h pharyngeal pH monitoring in healthy volunteers to determine the normal reference values in the Korean population. Thirty healthy subjects underwent ambulatory 24-h pharyngeal pH monitoring with glass electrodes positioned 1 cm above the upper esophageal sphincter and 5 cm above the lower esophageal sphincter, based on esophageal manometry after upper gastrointestinal endoscopy. LPR occurred in about one half of the healthy volunteers without any significant association with age, gender and body mass index. Pharyngeal acid reflux occurred mainly in the upright position. At the 95th and 90th percentile, after the exclusion of mealtimes, the upper limits of normal (ULN) for pharyngeal acid exposure were 0.41% and 0.18%. The ULNs for the number of pharyngeal acid events were 12.8 and 5.0. The corresponding ULNs for the esophagus were 5.1% and 3.8% and 62.7 and 32.6. The findings of this study help establish the reference standards for LPR in Korean patients.

We performed a prospective study of asymptomatic adult volunteers to establish normative values of pharyngeal pH using a novel pH probe.

The Dx-pH probe is a novel pH device capable of measuring liquid and aerosolized acid levels. Twenty asymptomatic patients (Reflux Symptom Index less than 10 and Reflux Finding Score less than 6) underwent simultaneous investigation with this probe placed in the oropharynx and a dual antimony probe placed in the hypopharynx and esophagus. The reflux parameters measured from the oropharyngeal probe included the percentage of time and the number of events in which the pH was less than 5.5,5.0,4.5, and 4.0.

The upper limits of normal (95th percentile) for the number of events below pH of 5.5, 5.0, 4.5, and 4.0 per 24-hour period were 16.6, 10.7, 7.4, and 0.2, respectively. The upper limits of normal (95th percentile) for an acid exposure time below pH of 5.5, 5.0, 4.5, and 4.0 per 24-hour period were 820 seconds, 385 seconds, 75 seconds, and 3 seconds, respectively.

Normative pharyngeal pH values are presented. Further studies are required to determine clinical relevance.

Diagnostic testing for GERD has evolved to include multi esophageal sites (distal, proximal and hypopharyngeal monitoring), wireless pH, and oropharyngeal devices. The versatility of the devices has increased our ability to better understand the role of acid reflux in various disorders involving reflux of acid. Wireless pH monitoring improves patient comfort and allows monitoring for gastroesophageal reflux events over several days. Ambulatory MII-pH monitoring is another exciting diagnostic tool, which is capable of detecting more than one type of reflux and achieves higher sensitivity and specificity to detect GERD than endoscopy or pH-metry. It is useful in patients with either typical or atypical reflux symptoms who are refractory to proton pump inhibitor (PPI) therapy. In this setting, MII-pH can be performed on PPI therapy to assess the efficacy of PPIs and the role of nonacid or acid reflux in persistent symptoms.

The association between gastroesophageal reflux disease (GERD) and extraesophageal symptoms is poorly understood and difficult to document. pH monitoring in this group of patients has resulted in conflicting data due to lack of diagnostic sensitivity. Recently, a new sensitive pH device for detection of liquid and aerosolized droplets in the oropharynx (The Dx-pH Measurement System [Dx-pH]) has become available. Our hypothesis is that we will be able to improve our ability to identify and understand this group of patients with this device. The aim of this preliminary observation study was to compare the results of this new device to the standard esophageal and pharyngeal pH probes in a small group of patients with extraesophageal symptoms. Patients with suspected extraesophageal GER symptoms underwent traditional 24-hour esophago-pharyngeal pH monitoring (24pH) simultaneous with Dx-pH monitoring in the oropharynx. Tracings were reviewed for comparison and correlation between the two probes, with an event in the Dx-pH Probe being defined as a rapid drop >3 standard deviation from baseline. Fifteen patients (10 females, 5 males) with mean age of 57.5 years (range, 25-75) were studied. The predominant chief complaint included 12/15 chronic cough, 2/15 asthma; and 1/15 throat clearing. All Dx-pH events were preceded and associated with distal esophageal pH drops in a progressive ante grade manner. Ten patients had 1-13 abnormal oropharyngeal pH events as measured by Dx-pH monitoring with a total of 48 events. The median pH of reflux events had a statistically significant increase from 3.1 at the distal esophageal probe to 5.2 at the pharynx and 5.6 at the oropharynx, the latter being 80% higher than the distal esophageal probe (P<0.001). The percentage of acid events decreased in a cephalad manner from 66.7% at distal esophagus to 25% at the pharynx and only 6.25% at the oropharyngeal Dx-pH Probe, with the remaining events being weakly acidic. Dx-pH Probe is a new sensitive oropharyngeal pH device whose values correlate well with the gold-standard 24-hour pH device, and appears to accurately detect pH events that begin at the distal esophagus and travel upward to the oropharynx. This device suggests that supraesophageal events manifest themselves as rapid pH drops (>10%), which are likely not to be identified using the standard criteria of pH <4 due to the gradient of increasing pH from the lower esophagus to the oropharynx.

The utility of laparoscopic Nissen fundoplication in the treatment of laryngopharyngeal reflux symptoms remains controversial. We hypothesized that a carefully selected population with these symptoms would benefit from antireflux surgery.

Sixty-one consecutive patients have undergone antireflux surgery for laryngopharyngeal reflux at a single institution. Preoperative evaluation including upper endoscopy, laryngoscopy, and 24-h ambulatory pharyngeal pH probe monitoring confirmed the diagnosis. Patients completed two validated symptom assessment instruments preoperatively and at multiple time points postoperatively.

Patients were followed for up to 3 years with a mean follow-up of 15.2 months. A significant improvement in reflux symptom index score (preoperative= 1.5+/-7.4 vs 3 years=12.4+/-10.9, p<0.01), laryngopharyngeal reflux health-related quality of life overall score (preoperative=55.0+/-26.0 vs 3 years=11.3+/-13.9, p<0.01), and symptom domain scores (voice, cough, throat clearing, and swallowing) occurred within 1 month of surgery and remained improved over the course of the study.

Laparoscopic Nissen fundoplication is effective in relieving the symptoms of laryngopharyngeal reflux in a carefully selected patient population. Benefits are seen within 1 month of surgery and persist for at least 3 years.

To investigate and compare the prevalence of pharyngeal reflux (PR) events in normal controls and patients with clinically diagnosed reflux laryngitis.

A systematic review of the literature was performed to identify all prospective studies on the results of 24-hour double-probe (pharyngeal and esophageal) pH monitoring in normal controls and in patients with symptoms and/or signs of reflux laryngitis.

Eleven relevant studies on 192 normal controls and 13 studies on 512 patients with reflux laryngitis were identified. One or more PR events were detected in 51 normal controls (22.9%; 95% CI, 13.9% to 33.3%) and in 154 of 422 patients (38.3%; 95% CI, 25.4% to 52.1%). There is no significant difference in the prevalence of PR events between normal controls and patients with reflux laryngitis (P = 0.079). In addition, the prevalence of PR events in patients with reflux laryngitis is much lower than reported in previous reviews on this subject.

This systematic review calculated that (1) only a minority of patients with clinically diagnosed reflux laryngitis will show PR events, and (2) there is no significant difference between the prevalence of PR events in patients with reflux laryngitis and healthy controls. At the moment, there is no reliable means to confirm reflux of gastric juice in patients with suspected reflux laryngitis. This diagnostic vacuum is fundamental and may pose important questions at the current concept of reflux of gastric juice as a common cause of laryngopharyngeal inflammation.

Published yields of pH monitoring for suspected laryngopharyngeal reflux (LPR) vary greatly. Hypopharyngeal pH artifacts may be responsible for these inconsistencies.

To determine the impact of potential artifacts on pH monitoring of the hypopharynx and esophagus.

Patients with suspected LPR were prospectively studied. Single-catheter, triple-sensor pH monitoring was performed off antireflux therapy. Subjects recorded meal times and marked liquid swallows outside of meals on the data recorder. Results were analyzed by excluding six potential pH artifacts individually and all together. Positive pH test was defined as three or more reflux episodes in hypopharynx, total percent of time pH less than 4 was 1.0% or greater in the proximal esophagus, and total percent of time pH less than 4 was 4.2% or greater in the distal esophagus. Wilcoxon rank sum and chi-square tests were used.

Thirty-eight subjects (24 females; median age, 47 yr) completed the study. A total of 2,225 hypopharyngeal pH drops less than 4 were identified; 48% were short pH drops at less than 5 seconds, 17% within meal periods, 16% liquid swallows outside of meals, 16% isolated proximal pH drops, 12% pH out of range, and 5% pH drift. Eighty percent of the hypopharyngeal pH drops were at least one of the potential pH artifacts. The yield of the hypopharyngeal sensor was reduced by 45% (from 92% to 47%) after all potential pH artifacts were excluded. Yields of proximal and distal esophageal pH sensors were reduced by 19% and 8%, respectively, significantly less than the hypopharyngeal sensor (P < .01).

Patients should record all liquid swallows outside of meals. It is essential to exclude all potential artifacts for hypopharyngeal pH monitoring in patients with suspected LPR.

Laryngopharyngeal reflux (LPR) may be a contributing factor in chronic hoarseness. The association of LPR with functional dysphonia (FD), the most common voice clinic diagnosis, is unknown. We attempted to determine whether patients with FD have a higher rate of laryngeal exposure to acidic stomach contents than do healthy volunteers.

We recruited through the voice clinic 23 patients who had had persistent dysphonia for 3 months. Pregnancy, major structural laryngeal abnormality, and vocal fold paralysis were exclusion criteria. Eight healthy volunteers were recruited. The subjects gave informed consent to enter the study, which had the approval of our hospital ethics committee. The patients and control subjects underwent 24-hour dual-probe pH-metry.

Twenty-two patients and 6 control subjects completed the study. Overall, there seemed to be no statistical differences between patients and controls on all but 2 channel 1 pH-metry parameters. These were the longest reflux episode (seconds) in a supine position, and the fraction of time the pH was less than 4 in a supine position. Both of these time periods were longer in patients than in the controls (p < .05).

Our study demonstrated an association between LPR and FD for 2 pH parameters. Larger studies are required to assess the potential relationship between nonorganic dysphonias and reflux. Furthermore, the presence of a multifactorial causation of FD, including "medical" and psychological causes, should be addressed in future studies.

Investigations and technical advances have enhanced our understanding and management of gastroesophageal reflux disease. The recognition of the prevalence and importance of patients with endoscopy-negative reflux disease as well as those refractory to proton pump inhibitor therapy have led to an increasing need for objective tests of esophageal reflux. Guidelines for esophageal reflux testing are developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee and approved by the Board of Trustees. Issues regarding the utilization of conventional, catheter-based pH monitoring are discussed. Improvements in the interpretation of esophageal pH recordings through the use of symptom-reflux association analyses as well as limitations gleaned from recent studies are reviewed. The clinical utility of pH recordings in the proximal esophagus and stomach is examined. Newly introduced techniques of duodenogastroesophageal reflux, wireless pH capsule monitoring and esophageal impedance testing are assessed and put into the context of traditional methodology. Finally, recommendations on the clinical applications of esophageal reflux testing are presented.

Laryngopharyngeal reflux (LPR) is one of the main factors behind different laryngeal pathology according to the Western literature. Literature reported that the prevalence of gastroesophageal reflux disease (GERD) in Chinese population was considerably lower than that in Western countries. To date, however, there is no study to evaluate the prevalence of pH-documented LPR in the Chinese ethnicity.

We thus recruited 28 consecutive Chinese patients with reflux symptoms including globus, throat discomfort, throat clearing, chronic cough, or burping lasting more than 1 month in the preceding 1 year, together with stroboscopic evidence suggestive of reflux laryngitis according to the reflux finding score in our study. All patients underwent thorough head and neck examination and transnasal endoscopic assessment. The prevalence of pH-documented LPR and GERD was then documented using ambulatory 24-hour pH biprobe study.

Six (21%) of the 28 patients had pH-documented LPR. Four (14%) of the 28 patients had GERD with 3 of them having concomitant LPR. Only burping was associated with pH-documented LPR (P < .05). No relationship was observed between pH-documented LPR and other factors, including age, sex, other reflux symptoms except burping, and the reflux finding score.

Chinese patients do have and present with symptoms of extraesophageal reflux, and we observed a lower prevalence of pH-documented LPR in Chinese patients with clinically suspected reflux laryngitis compared with white patients.

To identify variables contributing to discrepant gastroesophagopharyngeal acid reflux (GEPR) findings and to critically assess the prevalence of GEPR in healthy individuals and patients with reflux laryngitis (RL).

Quantitative systematic review.

Pharyngeal pH monitoring studies of healthy individuals and patients with RL were identified through a MEDLINE search of publications between 1966 and 2003. Pooled results of the measured pharyngeal acid exposure characteristics and the prevalence of GEPR events were analyzed. Statistical comparisons were performed using a chi 2 test.

The study included 181 controls and 184 RL patients. Subjects' age ranged from 19 to 85 years. Gastroesophagopharyngeal acid reflux events were detected at 1, 2, and 4 cm above upper esophageal sphincter (UES) and 0.5 cm below arytenoids, with varying rates. The prevalence of GEPR ranged from 0% to 83% in controls and 27% to 86% in RL. After excluding the healthy subjects with abnormal esophageal acid exposure, prevalence of GEPR decreased from 35% to 17% (P<or=.002). Gastroesophagopharyngeal acid reflux in RL was significantly more prevalent than in the entire group of controls as well as in controls without abnormal esophageal acid exposure (P<or=.001).

The prevalence of GEPR in controls and patients with RL varies in the studied 4 areas above the UES. The percentage of the subjects with GEPR increased as the probe was located more closely to the UES. Differences in demographic characteristics of the subjects, interventions used to select subjects, and pharyngeal pH monitoring techniques were identified as factors possibly contributing to inconsistent pharyngeal pH monitoring findings. The documented differences in methodology of existing studies make comparison of the studies difficult.

We report a meta-analysis of a series of studies in which 24-hour ambulatory pH monitoring was performed in 1) normal subjects, 2) the normal control subjects in studies of laryngopharyngeal reflux (LPR), and 3) the patients with LPR in these controlled studies. The statistical analysis utilized the fixed-effects model by Mantel-Haenszel and the random-effects mixed model. There were 16 studies from the past 12 years that fulfilled the inclusion criteria. They involved 793 subjects (264 normal and 529 with LPR). The numbers of positive pharyngeal reflux events for normal subjects and for patients with LPR differed with a p value of <.0001. There was also a significant difference in the mean percentage of acid exposure times between normal subjects and patients with LPR (p = .003). We conclude that the upper probe gives accurate and consistent information in normal subjects and patients with LPR. The numbers of reflux events and acid exposure times are most important in distinguishing normal subjects from patients with LPR. The technology and methodology of probe testing is quite reliable and is consistent on a worldwide basis.

To review recent literature on the possible mechanisms and role of gastroesophageal reflux in the etiology of laryngeal cancer, in patients with and without the accepted risk factors of smoking and alcohol consumption.

A recent systematic review was not conclusive. The issue remains a popular one for small-scale clinical surveys, when different inclusion criteria and a range of diagnostic tests are used.

After three decades of interest, there is still no unequivocal evidence for the role of reflux in the etiology of laryngeal cancer, whether in smokers or in nonsmokers.

Gastroesophageal reflux disease (GERD) is linked to several extraesophageal disease states including laryngitis, asthma, chronic cough, and noncardiac chest pain (NCCP). Although 24-hour pH monitoring is considered the "gold standard" in the diagnosis of typical GERD, it is also increasingly used in establishing the diagnosis of GERD in patients with extraesophageal symptoms. The clinical utility of pH monitoring in this patient population, however, remains controversial. In this article, the authors examine the role of pH monitoring in laryngitis, asthma, chronic cough, and NCCP.

To review recent advances in the diagnosis and treatment of extraesophageal reflux.

For most patients, the diagnosis of extraesophageal reflux relies on history and laryngoscopic exam. The reliability and reproducibility of reporting these measures may be improved with validated symptom questionnaires and standardized scoring of physical exam findings. Though dual probe pH monitoring has been the gold standard for diagnosis, it does not measure non-acid reflux events. Intraluminal impedance monitoring has the capability of measuring all esophageal reflux events (liquid, solid, gas) and may be useful in the diagnosis of non-acid reflux. Proton pump inhibitors have replaced histamine receptor antagonists as the mainstay of treatment for extraesophageal reflux. Histamine receptor antagonists are used predominantly for nocturnal acid breakthrough, or step-down therapy. Promotility and cytoprotective agents are used less commonly. Baclofen is currently being evaluated for its ability to decrease the incidence of transient lower esophageal sphincter relaxations and reduce post-prandial acid and non-acid reflux events. For individuals refractory to medical therapy, laparoscopic fundoplication techniques have proven efficacy in relieving some symptoms; the long-term benefit is not yet known. There is yet no established data on the effects of endoluminal therapies on extraesophageal reflux symptoms.

The diagnosis of extraesophageal reflux for most patients relies on history and laryngoscopic exam. The diagnosis can be further verified by dual probe pH and impedance monitoring. Proton pump inhibitors are the mainstay of treatment. Laparoscopic fundoplication is proven to relieve symptoms, but there is yet no data on the effects of endoluminal therapies on extraesophageal reflux symptoms.

Gastroesophageal reflux (GER) disorder was studied in children and adolescents with chronic and/or recurrent rhinosinusitis not associated with bronchial asthma. Ten children with a clinical and radiological diagnosis of chronic and/or recurrent rhinosinusitis, consecutively attended at the Pediatric Otolaryngology Outpatient Clinic, Federal University of São Paulo, were evaluated. Prolonged esophageal pH monitoring was used to investigate GER disorder. The mean age of the ten patients evaluated (eight males) was 7.4 +/- 2.4 years. Two patients presented vomiting as a clinical manifestation and one patient presented retrosternal pain with a burning sensation. Twenty-four-hour esophageal pH monitoring was performed using the Sandhill apparatus. An antimony probe electrode was placed in the lower third of the esophagus, confirmed by fluoroscopy and later by a chest X-ray. The parameters analyzed by esophageal pH monitoring included: total percent time of the presence of acid esophageal pH, i.e., pH below 4 (<4.2%); total number of acid episodes (<50 episodes); number of reflux episodes longer than 5 min (3 or less), and duration of the longest reflux episode (<9.2 min). One patient (1/10, 10%) presented a 24-h esophageal pH profile compatible with GER disorder. This data suggest that an association between chronic rhinosinusitis not associated with bronchial asthma and GER disorder may exist in children and adolescents, especially in those with compatible GER disorder symptoms. In these cases, 24-h esophageal pH monitoring should be performed before indicating surgery, since the present data suggest that 10% of chronic rhinosinusitis surgeries can be eliminated.

To determine the prevalence of acid reflux into the nasopharynx in patients with chronic sinusitis.

Prospective study of patients presenting to a specialist rhinology practice with chronic sinusitis.

Forty patients with chronic sinusitis underwent ambulatory 24 hour pH testing. The mean age of the patients was 56.3 years (25 Female, 15 Male). The studies were performed using a specially developed bifurcated 4 channel pH probe, incorporating 2 circumferential sensors positioned at the naso- and hypo-pharynx, and 2 unidirectional sensors positioned at the proximal and distal esophagus.

The circumferential band sensors yielded a stable recording largely free of artefact allowing meaningful recordings to be obtained from thirty-seven patients. Twelve patients (32.4%) were diagnosed with gastroesophageal reflux. A total of 809 reflux episodes were recorded. Of these, 596 (73.7%) reached the distal esophagus, with 187 (23.1%) and 24 (3.0%) reaching the proximal esophagus and hypopharynx respectively. Only 2 episodes (0.2%) were recorded in the nasopharynx. This occurred in 2 of 37 patients (5%).

Acid reflux into the nasopharynx is a rare event in patients with chronic sinusitis even though a significant proportion (32.4%) have abnormal 24 hour pH studies. It is likely that alternative mechanisms other than direct acid contact are involved in the pathogenesis of chronic sinusitis.

The past decade has witnessed increasing interest in the supraesophageal (ear, nose, and throat (ENT)) symptoms potentially caused by gastroesophageal reflux disease (GERD). Hoarseness, halitosis, problems with vocal presentations, excessive phlegm, frequent throat clearing, globus sensation, sore throat, cough, aspiration, laryngospasm, and laryngeal carcinoma are some, but not all of the ENT symptoms that have been attributed to GERD (1). The availability of highly effective medical and surgical therapies allows for control of these symptoms in many patients adding to the importance of accurately diagnosing GERD.

Laryngopharyngeal reflux is of great interest to otolaryngologists, speech and language therapists, and gastroenterologists. This is a brief review of recent publications in the diagnosis of laryngopharyngeal reflux.

Otolaryngologic signs and symptoms can be found in 4 to 10% of patients with gastroesophageal reflux and those presenting for ear, nose, and throat evaluations. Laryngeal signs are not pathognomonic for laryngopharyngeal reflux because many of these signs can be found in healthy volunteers. A combination of signs and symptoms should be sought before suspecting this diagnosis. Most investigators consider pH monitoring the best currently available instrument to diagnose gastroesophageal reflux, even though it is not considered to be 100% sensitive and specific. Studies in normal volunteers indicate that a minimal number of reflux episodes reach the hypopharynx. The correlation between laryngeal signs and symptoms and pH-documented reflux is less than perfect, whereas the combination of pH testing and signs and symptoms is better in detecting patients with a favorable response to acid-suppressing therapy. Using an empiric trial of high-dose proton pump inhibitors over a prolonged period of time to diagnose laryngopharyngeal reflux is supported mainly by uncontrolled studies. To date, double-blind, placebo-controlled studies suggest that empiric trials of proton pump inhibitors may not have high accuracy for the diagnosis of laryngopharyngeal reflux.

Multidisciplinary trials are needed to establish the optimal combination of sign and symptom scores, reflux monitoring results, and empiric treatment trials for the most accurate diagnosis of laryngopharyngeal reflux.

Recent studies in adults and children suggest that combined multichannel intraluminal impedance and pH measurement (MII-pH) has the potential to become the new "gold standard" for gastroesophageal reflux testing. In combined MII-pH, reflux is detected by changes in resistance to alternating current induced by the presence of intraluminal materials with different conductivities, and is characterized as acid or nonacid reflux based on concomitant pH measurements. Proximal distribution and duration of nonacid reflux events, predominantly in postprandial periods and during acid-suppressive therapy, can now be quantified. The ability to associate symptoms with nonacid reflux events will help guide therapy in select groups of patients, such as patients with ongoing symptoms on acid-suppressive therapy as well as in the pediatric population.