BACKGROUND AND STUDY AIM
Capsule endoscopy, using the PillCam ESO and sending images at a rate of 4 frames per second (fps), has a high sensitivity and specificity in diagnosing gastroesophageal reflux disease (GERD) lesions. We tested a new device which produces images at a rate of 14 fps. The diagnostic performance and esophageal visualization of these two devices were compared.
PATIENTS AND METHODS
42 patients with GERD symptoms and eight patients with a history of Barrett's esophagus had an esophagogastroduodenoscopy (EGD). All patients underwent capsule endoscopy of the esophagus within 1 hour prior to EGD. The first 25 patients had a capsule endoscopy examination with the 4-fps device. The following 25 patients underwent capsule endoscopy under identical conditions but using the 14-fps device. The reader of the capsule endoscopy study was blinded to the EGD findings. A diagnosis of GERD or Barrett's esophagus was established with EGD. The findings at capsule endoscopy were compared with the EGD findings. We also examined how frequently the esophagus in its entirety was visualized by these two devices.
RESULTS
The 4-fps device diagnosed 16/19 cases of esophageal erosions or ulcers (sensitivity 84 %) and 6/8 cases of Barrett's esophagus (sensitivity 75 %). The 14-fps capsule diagnosed 16/16 cases of esophageal ulcers or erosions and 7/7 cases of Barrett's esophagus (sensitivity 100 %). The total diagnostic miss rate in the 4-fps group was 5/27 (18 %) whereas the diagnostic miss rate in the 14-fps group was 0/23 (0 %) P < 0.02). The upper esophageal sphincter (UES) was clearly identified in 6/25 patients (24 %) in the 4-fps group and in 20/25 patients (80 %) in the 14-fps group ( P < 0.01). The entire esophagus was well visualized in 3/25 patients (12 %) by the 4-fps device and in 19/25 (76 %) by the 14-fps device ( P < 0.01). The superiority of the 14-fps PillCam ESO capsule is consistent with the data obtained from fluoroscopic studies of swallowed PillCam capsules, showing that capsule speed may reach 20 cm/s. For the 14-fps PillCam this means one image transmitted per 3-cm segment at maximal capsule speed, therefore still allowing for full visualization of the entire esophagus.
CONCLUSIONS
Capsule endoscopy using the 14-fps PillCam ESO showed a greater sensitivity than that of the 4-fps device for identifying GERD. The 14-fps PillCam ESO was statistically superior to the 4-fps device in visualizing the opening of the UES and the entirety of the esophagus.