Assessment of optimal recording time to reduce incomplete wireless capsule endoscopy (WCE) due to functional gastrointestinal (GI) motility disorders.

Single-centre retrospective study of consecutive WCE examinations using different types of capsules: EndoCapsule S10, Pillcam SB3, OMOM and ANKON. Daytime (between 9h00 and 16h00) and overnight recordings were performed. All WCE were read in the conventional modus with a reading speed between 5 and 10 images/sec without the use of artificial intelligence.  

A total of 210 consecutive WCE examinations were analysed in 117 male (69±1y) and 93 female (65±2y) patients (age range 14-92y). Suspected small bowel bleeding was the leading indication (97%), except for n=7 patients. Bleeding presented as iron deficiency anaemia (66%), melena (26%) or unexplained rectal bleeding (8%) after normal upper and lower GI endoscopy. In 17% of all WCE active GI bleeding was diagnosed and in 41% potentially bleeding lesions like arteriovenous malformations, blue rubber bleb naevi, erosions or polypoid and tumoral lesions. In 29% the (potentially) bleeding lesions were located in the upper GI tract and in 6% in the lower GI tract within the reach of conventional endoscopy. In 34% WCE turned out to be normal. 37% of patients were referred for device-assisted enteroscopy based on the WCE findings. A total of 28 WCE (13%) were incomplete with the capsule not reaching the colon, with 7 because of technical failure (n=2) or mechanical stricture (n=5). The remaining 21 incomplete WCE were due to short recording time relative to the transit time (23% incomplete WCE when <10h recording time vs 3% incomplete WCE when <15h vs 1% incomplete WCE when >15h; p=0.0012 Chi-square).

WCE is an important first-line examination for suspected small bowel bleeding, with 17% of active bleeding recorded and an additional 41% of potentially bleeding lesions. However, those lesions are often found in the upper (29%) and in the lower (6%) GI tract despite prior normal upper and lower GI endoscopy. To avoid incomplete WCE due to slow GI transit a recording time of at least 15h seems mandatory.