Narrow-band imaging as an alternative to chromoendoscopy for the detection of dysplasia in long-standing inflammatory bowel disease: a prospective, randomized, crossover study

BackgroundNarrow-band imaging (NBI) is a novel technique that may represent an alternative method to chromoendoscopy (CE) for the detection of colitis-associated intraepithelial neoplasia (IN) in patients with long-standing inflammatory bowel disease (IBD).ObjectiveTo compare NBI with CE for the detection of IN.DesignProspective, randomized, crossover study.SettingAcademic hospital.PatientsPatients with clinically inactive colonic IBD (≥8 years).InterventionPatients underwent both CE and NBI in randomized order. Targeted biopsy specimens from abnormal areas were obtained. Pathological examination was regarded as the reference standard.Main Outcome MeasurementsNumber of false-positive and true-positive lesions in patients undergoing CE and NBI were compared as well as the proportion of patients with missed IN lesions.ResultsEighty patients were screened, of whom 20 were excluded. Mean ± standard deviation withdrawal time for CE was significantly longer than that for NBI (26.87 ± 9.89 minutes vs 15.74 ± 5.62 minutes, P < .01). Thirteen patients had at least 1 IN lesion on 1 of the examinations. In the per-lesion analysis, NBI resulted in a significantly inferior false-positive biopsy rate (P = .001) and a similar true-positive rate. The percentage of missed IN lesions and patients was superior with NBI, albeit without reaching statistical significance.LimitationsLesions were sampled immediately after detection, which precluded the possibility of paired analysis.ConclusionsNBI appears to be a less time-consuming and equally effective alternative to CE for the detection of IN. However, given the NBI lesion and patient miss rates, it cannot be recommended as the standard technique.