Safety, reliability and limitations of the given patency capsule in patients at risk of capsule retention: A 3-year technical review

Introduction The patency capsule may prevent capsule retention in high-risk patients. However data on its use in routine clinical practice is limited. Methods Patients referred to our institution between Feb-04 and Jan-07 were reviewed. The following data was collected: presenting symptoms; medical/surgical history; medication; radiology; patency/video capsule result; subsequent investigations; clinical outcomes. Results 373 patients were referred. In 315 (84%) 'low-risk' patients (no patency capsule): delayed transit occurred in three, with no cases of capsule retention. In 58 (16%) 'high risk' patients (patency capsule): asymptomatic retention occurred in eight, all with pathology despite normal prior barium studies in six; in four cases patency location was incorrectly assessed radiologically, leading to video capsule retention and surgery in one. Discussion Most patients can safely undergo capsule endoscopy without a patency capsule. The patency capsule appears safe and is indicative of pathology when retained. Assessment of patency capsule location post ingestion can be difficult, and if barium radiology is equivocal a limited abdominal computed tomography (CT) scan is suggested.