Novel magnetic tracking-based three-dimensional trajectory small bowel capsule endoscopy system for lesion localization: An in vivo animal study

BACKGROUNDCapsule endoscopy has become the first-line modality for small bowel diseases.However, lesion localization remains a significant clinical challenge for small bowel capsule endoscopy (SBCE).A novel magnetic tracking-based three-dimensional (3D) trajectory SBCE system has been developed for precise lesion localization. AIMTo evaluate the feasibility and efficacy of a 3D trajectory SBCE system for measuring pylorus-to-lesion distances in a canine model. METHODSIntestinal lesion models were surgically established in three dogs by suturing beads within the small bowel (three lesions per dog).Pylorus-to-lesion distances were intraoperatively measured as the reference standard.After one week's recovery, the three dogs underwent SBCE examinations, and the capsule localization system reconstructed 3D capsule trajectories to determine distances traveled by the capsule at lesion sites.Feasibility was defined as achieving complete small bowel mucosal visualization and uninterrupted 3D trajectory generation.Efficacy was assessed by lesion detection rate and accuracy of pylorus-to-lesion distance measurements against surgical standards. RESULTSAll three dogs successfully completed SBCE examinations with no adverse events.For feasibility evaluation, the localization SBCE system achieved full small bowel visualization and reconstructed continuous 3D capsule trajectories in all canine subjects.For efficacy assessment, the system detected 100% of lesions (9/9) and demonstrated a mean relative error of 5.03% ± 2.05% for pylorus-to-lesion distance measurement. / 23 CONCLUSIONThis animal study demonstrates the feasibility and efficacy of a novel magnetic tracking-based 3D trajectory SBCE system for accurate pylorus-to-lesion distance measurement, indicating significant clinical potential for precise lesion localization and guiding subsequent interventions.