Feasibility of Mini-sized Magnetically Controlled Capsule Endoscopy in Visualization of UGI and Small Bowel: a Randomized Controlled Clinical Trial

Magnetically controlled capsule endoscopy (MCE), with equally favorable diagnostic accuracy as conventional endoscopy, has become a painless noninvasive diagnostic modality in clinical practice. The more than 8 hours battery life of the MCE enables a further examination of the small bowel. In addition, it has been demonstrated that magnetic steering of capsule endoscopy improves the completion rate of small bowel examination by facilitating passage of the capsule through the pylorus, which further supported MCE as a practical modality for examination of both the stomach and small bowel. Previous studies have confirmed the great safety and efficacy of MCE for examination of patients with high-risk factors for standard gastroscopy, those long-time taking aspirin, aging patients and children.

However, this technique still has some limitations in clinical practice. Due to the large size of the capsule, some patients may be difficult to swallow the capsule, especially in children. A clinical trial reported that a certain number of children with ages ranging from 6 to 14 years fail to swallow the MCE by themselves for its big size (27mm*11.8mm). During the examination procedure of small bowel capsule endoscopy, measuring 26*11mm, in those under 10 years old of age, up to 87% of patients are unable to swallow the capsule. In adolescents, it is reported that more than one-third of patients have difficulties with swallowing standard size tablets. In addition, serious complications, such as aspiration of the capsule, often occur in the elderly who need more efforts to swallow the capsule. For those at any age unable or unwilling to swallow a capsule, endoscopic placement is required to deliver the capsule to the stomach or directly the duodenum. However, this procedure greatly increases patient's discomfort, examination costs and increase the risk associated with the endoscopic procedure, anesthesia. Thus, it is of great importance to make the capsule endoscopy easier to swallow in both children and adolescents.

Therefore, a mini-sized MCE highlighted with a diameter of 9.5mm, a length of 24.5mm, and a weight of 3.0g has been developed. This new type of MCE is approximately 0.6 times the conventional MCE (27mm*11.8mm) in volume and weight, and it is the smallest CE among all the reported capsules. Thus, this pilot study was conducted to clarify whether the mini-sized MCE can further optimize the process of swallowing the capsule and to verify whether the smaller size of the capsule will have influence on the examination procedure of the upper gastrointestinal tract and small intestine.