An inductively-coupled, detachable receiver coil system for use with magnetic resonance compatible endoscopes

Purpose: To construct an inductively-coupled receiver coil system for use with a magnetic resonance (MR) compatible endoscope, and to evaluate its use in a pilot group of patients with esophageal cancer. Materials and Methods: An inductively-coupled coil system, comprising a saddle geometry cylindrical receiver coil fitted as a sleeve around the endoscope tip and a pick-up coil housed within a channel of an MR-compatible endoscope, was designed and developed for use at 0.5 T. Twenty-three patients with esophageal cancer were recruited for MR endoscopy. In 17 cases, the endoscopic coil system was used in conjunction with an external surface coil in order to obtain information from the surrounding mediastinum. The examination took 40-50 minutes. Results: MR imaging using the inductively-coupled endoscopic coil was successful in 21 cases (one failed intubation and one artifact from unrelated external source). Image artifact was largely due to respiration and global patient motion in sedated individuals undergoing endoscopy. Conclusion: Inductively-coupled coil systems may be used with endoscopes to allow improved safety through increased patient-system isolation and detachability of coils and electronics for repair or replacement with coils tuned for different frequencies.