The Diagnostics of Extraesophageal Reflux With the Restech System in Patients With Chronic Rhinosinusitis

Introduction The problems of relation between some of the ENT diseases (posterior laryngitis, granulomas of the vocal cords, globus pharyngeus and others) and the extraesophageal reflux (EER), which is associated by the refluxate penetrating above the level of the upper oesophageal sphincter, has been studied more intensely especially during the last several years. The golden standard in the diagnostics of EER remains the dual-channel 24-hour pH-metry. The methodology of this procedure has been standardized in the past several years and differs significantly from the oesophageal pH-metry carried out by gastroenterologists (the upper probe is usually placed above the level of the upper oesophageal sphincter). The pH-metry enables us to monitor especially the impact of EER upon diseases of the oesophagus and hypopharynx. Non-existence of a simple and sensitive method was a barrier in a more detailed examination of the relations between EER and the more proximally located parts of the upper respiratory tract (nasopharynx, nasal cavity and paranasal sinuses, middle-ear cavity). The problem of "classical" pH-metry probes lies in the fact that unless the sensor is covered by a mucosa, it dries out and the record is not accurate.

The Restech system was introduced two years ago, with the aim to improve the EER diagnostics in oropharynx and nasopharynx. The sensor of a very sensitive antimony probe is positioned at the tip of a 1,5 mm catheter, which is inserted through the nose behind the uvula (the exact positioning is controlled with the use of the illuminating end of the catheter). High sensitivity of this device enables to measure not only the pH of the liquid but also of small aerosol drops - so called aerosol reflux. The examination takes 24 hours, the data are being transferred wirelessly into a recording device. Normative data of a non-symptomatic group have also been defined. The advantages of this method, when compared with the dual-probe 24-hour pH-metry are a higher sensitivity, easier accomplishment and better compliance of the patient population. However, a wider comparison data for different pathological conditions are still missing.

EER is considered to be one of possible factors which may contribute to the onset or worsen existing chronic rhinosinusitis (CHR). It is a well-known fact that a part of the patients with CHR undergoing endonasal surgery suffer from an early recurrence of the disease. DelGaudio found out, using a 3-channel pH-metry, that adult patients with refractory or recurrent chronic rhinosinusitis experience a significantly higher number of nasopharyngeal refluxes, when compared to the patient population presenting no symptoms after surgical treatment; and recommends anti-reflux therapy as a part of treatment in patients with refractory chronic rhinosinusitis. The same view is supported by another author, Pincus, who in his clinical trial confirmed a good effect of proton pump inhibitors in the treatment of such patients. According to EPOS (European Position Paper On Rhinosinusitis and Nasal Polyps, 2007), the relation between EER and chronic rhinosinusitis is currently at the level of a III degree evidence. EPOS also summarises the fact that patients suffering from chronic rhinosinusitis and pH-metry proven EER, present significantly more frequently alleviation of the symptoms following an anti-reflux therapy. In that respect, EPOS recommends further clinical investigation of this problem.

It is possible to assume that the Restech system enables a more precise diagnostics of the patients (when compared to pH-metry), however this system has not been tested in the diagnostics of EER in patients with CHR, either in the Czech Republic or abroad. If the proposed relation is confirmed, it will mean a dramatic change in the process of treatment in a part of the CHR patients, suffering at the same time from EER ("more urgent" recommendation of anti-reflux therapy, especially in patients with recurrent and refractory CHR).

It has been proved in the past that a part of the patient population with difficult to control asthma bronchiale also suffers from EER, and that these patients profit greatly from a treatment using proton pump inhibitors. Also a part of the patients with CHR suffers from asthma bronchiale or a complete ASA syndrome. It is possible to assume that EER, having a negative impact upon the asthma bronchiale, may have a similar negative effect upon CHR. The mutual interrelations among EER, CHR and asthma bronchiale have not been thoroughly studied; one of the aims of the proposed project is also to explore these relations.