This study evaluates the diagnostic accuracy, safety and acceptability of transnasal endoscopy (TNE) for a diagnosis of Barrett's esophagus (BE). This is a cross-over randomised trial, whereby patients receive two endoscopic procedures 2-4 weeks apart and will be randomised to receive either TNE or standard endoscopy followed by the other procedure.

Background: The incidence of esophageal adenocarcinoma (EAC) has drammatically increased in the Western World in the last 30 years. Furthermore it often presents in the late stages and the prognosis remains poor with an overall 5-year survival of 10-15%. Early detection is possible since most cases of EAC develop from a precursor condition, Barrett's esophagus (BE), via a metaplasia-dysplasia-adenocarcinoma sequence. BE can be diagnosed with an upper GI endoscopy.

Un-sedated trans-nasal endoscopy (TNE) may be safer and less expensive than standard endoscopy (SE) for detecting BE. Emerging technologies require robust evaluation before routine use.

Objective: To evaluate the sensitivity, specificity, and acceptability of TNE in diagnosing BE compared with those of SE.

Design:Prospective, randomized, crossover study

Setting:Single, tertiary-care referral center.

Patients: patients with BE or those referred for diagnostic assessment will be enrolled consecutively .

Intervention: All patients will undergo TNE followed by SE or the reverse. Spielberger State-Trait Anxiety Inventory, short-form questionnaires, a visual analogue scale, and a single question addressing preference for endoscopy type will be administered.

Main Outcome Measurements: Diagnostic accuracy for BE and tolerability of TNE and SE.

The primary aim of this study is to evaluate the sensitivity and specificity of ultrathin endoscopy in diagnosing BE (using standardised endoscopic and histopathological criteria) compared with the gold standard white light conventional endoscopy.

The secondary aims include to assess the acceptability, optical quality and safety of the two interventions.

The study will consist of two phases. In a first large phase 80% of the target (90 patients) we will evaluate conventional TNE (Fujinon). In a second phase the remaining of the patients (25) will be evaluated with a disposable office-based system (Endosheath).

Inclusion Criteria:

1. Age: > 18 years and <75 years
2. Patients who have given informed consent and who are capable of filling in the questionnaire.
3. Patients requiring endoscopy for dyspepsia or follow-up evaluation and patients with a prior diagnosis of BE (defined as minimum Barrett's length of 2cm - according to M level of Prague C & M classification) with specialized intestinal metaplasia on histological confirmation.

Exclusion Criteria:

1. Previous upper GI tract or upper respiratory tract surgery or known upper GI tract abnormality (e.g. pharyngeal pouch).
2. Coagulopathy or on anticoagulants
3. Active or severe cardiopulmonary disease or liver disease
4. Active GI bleeding
5. Patients with alarm symptoms referred to the fast track service and any patient with dysphagia
6. Patients requiring possible endoscopic therapy
7. Patients with high-grade dysplasia or intramucosal carcinoma in BE requiring extensive evaluation and biopsy