Background: A narrow band imaging (NBI) endoscopy system has been developed that allows superficial surface imaging of esophageal tissue in vivo.
Objective: The objective was to assess the potential of NBI for prediction of histology during screening and surveillance endoscopy in patients with Barrett's esophagus (BE).
Design: A prospective cohort study.
Setting: Veterans Affairs Medical Center.
Patients: Fifty-one patients with known or suspected BE.
Methods: NBI images were graded according to mucosal pattern (ridge/villous, circular and irregular/distorted) and vascular pattern (normal and abnormal), and correlated with histology in a prospective, blinded manner.
Main outcome measurements: Biopsy-confirmed intestinal metaplasia (IM) and dysplasia were used as the outcome measures.
Results: Of 51 patients (mean BE length 3.5 cm), 28 had IM without dysplasia, 8 had low-grade dysplasia (LGD), 7 had high-grade dysplasia (HGD), and 8 had cardiac-type mucosa. The sensitivity, specificity, and positive predictive value of ridge/villous pattern for diagnosis of IM without HGD were 93.5%, 86.7%, and 94.7%, respectively. The sensitivity, specificity, and positive predictive value of irregular/distorted pattern for HGD were 100%, 98.7%, and 95.3%, respectively. If biopsies were limited to areas with irregular/distorted pattern, no patient with HGD would have been missed. However, NBI was unable to distinguish areas of IM from those with LGD.
Limitations: The open study design without a control group was the main limitation.
Conclusions: NBI is a novel diagnostic tool with a high degree of accuracy for the detection of metaplastic and dysplastic tissue within the BE segment.