Introduction Delayed gastric emptying can be a significant factor in incomplete small bowel capsule endoscopy (SBCE). This has been addressed by using prokinetic agents, albeit with the need for cannulation or intramuscular (IM) injections and the small risk of adverse drug reactions. Recently a manoeuvrable small bowel (SB) capsule has become available using a handheld magnet to control movement. We compared this magnetically steerable method to a standard protocol using metoclopramide for enhancing gastric transit of the SB capsule.
Method Single centre, randomised controlled trial involving 121 patients attending for SBCE using MiroCam Navi (Intromedic, Seoul, Korea). Patients were randomised to either the standard (control) group or the steerable capsule (intervention) group. The control group were mobilised for 30 min after ingestion of the capsule, followed by IM metoclopramide 10 mg if the SBCE had failed to enter the SB. The intervention group ingested a gastric distention volume of 1000 mls of water with 5 drops of simethicone prior to SBCE. Positional change and magnetic steering was used to manipulate the SBCE into the duodenum. If unsuccessful after 30 min, the patient transferred to the standard protocol. 60 patients per group were required to achieve 80% power, assuming a completion rate of 70% for the control protocol, improving to 90% with the intervention. Ethics: 13/YH/0358.
Results 121 patients were recruited (60 to the control group, 61 to the intervention group: mean age 49 years (range 21–85), 61 females). 2 patients were excluded due to gastric retention of the capsule. Mobility, particularly tilting and rotational movements was achieved with reasonable precision in the gastric cavity. However, this became challenging in the pre-pyloric region due to variability in anatomical orientation and peristaltic contractions. Clarity of gastric mucosal views was excellent. Gastric transit time (GTT) was longer in the intervention group but this did not reach statistical significance (median 23 vs 51 min Mann-Whitney U=1487, p = 0.116). There was no significant difference in capsule endoscopy completion rate (CECR) between the two groups (χ² p = 0.395). Examining the intervention sub-group: no correlation between body mass index (BMI) or waist-hip ratio (WHR) and GTT was demonstrated (r = 0.002 and r = 5.98 respectively). Similarly no significant difference between WHR (p = 0.938) or BMI (p = 0.507) and CECR was noted.
Conclusion Magnetic steering of a SB capsule is unable to overcome pyloric contractions to enhance gastric emptying. However, mobility and image clarity within the gastric cavity was excellent, Therefore, with further improvements this technique could potentially be harnessed to enable capsular examination of the gastric cavity.
Disclosure of interest None Declared.