Clinical Utility of Patency Capsule in Pediatric Video Capsule Endoscopy

Abstract

Introduction: Capsule Endoscopy retention is a concern among pediatric patients who undergo video capsule endoscopy. The patency capsule(PC) has been used to determine small bowel patency. An abdominal x-ray is often used to determine if the PC has passed through the small bowel within 30 hrs. We report our experience of the use of the agile patency capsule in pediatric capsule endoscopy. Methods: We retrospectively reviewed the use of the (PC) in our cohort of 528 pediatric patients undergoing capsule endoscopy. There were 86 patency capsules performed. Patients ingested the patency capsule 30 hours prior to obtaining an abdominal x-ray. The abdominal x-ray was read by radiologists and also by the gastroenterologist performing the capsule endoscopy study. The indications for the patency capsule evaluation included known Crohn's disease 38 (44.2%) and Ulcerative Colitis 5 (5.81%). Results: 86 patients underwent patency capsule study along with and abdominal x-ray prior to capsule endoscopy. In 40 (46.5%) of abdominal x-rays, the PC was not seen at 30 hours post ingestion, confirming complete passage throgh the GI tract. In 44 (51.2%) abdominal x-rays, the radiologist reported presence of the PC in the abdomen. In 27(31.4%) of these 86 x-rays where the PC was noted in the abdomen, the radiologist commented that the PC was in the colon. In 15 (17.4%) abdominal x-rays, the location of the PC was not specifically identified to be within the colon. Instead, it was reported to be in various locations such as the right lower quadrant. The gastroenterologist therefore was required to further interpret these x-ray studies to determine whether these 15 PCs were in the colon. In 2 (2.3%) abdominal x-rays studies, the radiologist interpreted the capsule to be in the distal ileum or cecal region. These PC's were confirmed by colonoscopy to be retained in the distal ileum. Capsule endoscopy was therefore not performed on these two patients. The remaining 84 patients sucessfully completed video capsule endoscopy. The patency capsule retention rate within the small bowel at 30 hours post injestion was found to be 2.3% of patency capsule studies. Conclusion: The patency capsule is useful in preventing capsule endoscope retention and often requires careful interpretation by both the radiologist and the gastroenterologist.Figure 1Figure 2