The yield and safety of string capsule endoscopy in patients with dysphagia

Background: Dysphagia is a contraindication for the use of conventional capsule endoscopy (CE). Because string CE (SCE) allows for the immediate retrieval of the device, it eliminates the risk of capsule retention. Objective: To assess the yield and safety of SCE in patients with dysphagia. Design: Comparative study of SCE and EGD. Setting: Phoenix Veteran Affairs Medical Center. Patients and Interventions: Patients with dysphagia underwent SCE and EGD. Results: In 40 patients with dysphagia, the EGD findings were normal in 13 (32.5%); Schatzki's ring in 10 (25%); esophageal tumors in 9 (22.5%), with 1 of these having 2 separate and distinct malignancies; erosive esophagitis in 4 (10%); strictures in 2 (5%); and a web and large esophageal varices in 1 patient each (2.5%). The sensitivity of SCE for diagnosing anatomic pathology as the likely cause of dysphagia was 92.9%, with a specificity of 92.3%, a positive predictive value of 96.3%, and negative predictive value of 85.7%. The overall agreement between SCE and EGD was 92.7% and the kappa index was 0.83. There were no complications with either procedure. There was no case of capsule retention. The SCE recording time was 385.8 seconds; 77.5% patients preferred SCE to EGD. Conclusions: (1) SCE was safe, well tolerated, and accurate for the diagnosis of pathology responsible for dysphagia; (2) SCE was preferred to EGD by more than three fourths of patients; (3) SCE can be safely performed in patients with dysphagia.