Is It Really Better A Two-Viewing-Dome Capsule for the Esophagus?. A Prospective, Blinded Trial

Background and Study Aim: The superiority of the current PillCam ESO (14 frames per seconds) over the prototype that took 4 frames per second and the PillCam SB has been addressed in various reports. Meanwhile no studies have depicted the exact role of having two viewing cupules. We aimed to compare the differences in view between both ends and establish the benefits of having two cupules. Material and Methods: Esophageal capsule endoscopy (ECE) of 25 patients with chronic GERD (12F/13M; 55,81 ± 15,53 years) were analyzed. One investigator reviewed the video corresponding to one end of the capsule and another investigator reviewed the other end for each study. The investigators were blinded to each other results. They were required to annotate the number of frames visualizing the Z-line, the degrees of Z-line viewed, the number and kind of findings, the number of frames of findings and the causes for incomplete visualization of Z-line. These outcomes were analyzed in the end with better results in each examination, in the end with worse results, and in the whole examination (with both ends). Results: The lesions detected by ECE were erosions, petechias, polyps, diverticula and Barrett esophagus. In the better results end group (BREG) the Z-line was visualized in more than 270 degrees in another 19 patients, but only in 3 patients in the worse results end group (WREG) (p < 0.05). The number of frames of Z-line (45,56 ± 65,62 vs 5,96 ± 11,14), the number of findings (15 vs 9), and the number of frames of findings (444 vs 73) were also significantly higher in BREG than in WREG (p < 0.05). The review featuring both ends of the capsule improved the results of the BREG achieving a complete visualization of the Z-line in three studies that only achieved 270 degrees with one end, raising the number of findings from 15 to 19 (p = 0.05) and the number of frames of findings from 444 to 517 (p < 0.005). Main causes for non visualization were the presence of bubbles, fast capsule passage, and capsule position in the Z line. Conclussions: The presence of two viewing domes in the capsule improves the visualization of Z-line, identifies more lesions and provides a higher number of images of the lesions compared with the one-viewing-dome capsule. These results could be applicable to the small bowel study, so a two-viewing-dome SB prototype will be welcome.