title: Magnetic anchor for more effective endoscopic mucosal resection.
abstract: BACKGROUND
  Technical difficulties are involved in endoscopic mucosal resection (EMR) of gastric cancer since it is a "one handed surgery". These difficulties prevent this technique from being indicated for larger lesions, even when it can possibly be performed for patients with such lesions. If microforceps could assist EMR, this procedure would become easier and safer. Since magnetic force can control objects without direct contact, it can be applied to control microforceps internally in assistance with EMR.
  
  
  METHODS
  We developed a magnetic anchor consisting of three parts: a magnetic weight with dimensions of 1.0 x 1.0 x 1.5 cm, microforceps and a connecting thread. Endoscopic clips used in hemostasis were used as the microforceps of the magnetic anchor in this study. The magnetic control system consisted of a 0.68 kOe/10 cm/100 A electromagnet, 350 mm in diameter and a circumventing positional frame. The microforceps were inserted into a sheath within the endoscope, and the magnetic weight was secured to the tip of the sheath protruding from the endoscope. The magnetic anchor, along with the endoscope, was inserted through an overtube into the gastric cavity of a swine under general anesthesia. The magnetic anchor was used in a manner similar to that in standard surgery, and EMR was thereby performed.
  
  
  RESULTS
  The mucosa to be resected was satisfactorily dragged and stabilized. The magnetic anchor facilitated EMR, regardless of the technical skills of the endoscopist and region of the stomach at which the technique was performed.
  
  
  CONCLUSIONS
  The magnetic anchor is considered to have alleviated some technical problems involved in EMR. It has the potential for making EMR a safer and quicker procedure for the treatment of early gastric cancer, when appropriately indicated.
authors.affiliation: Cancer Screening Technology Division, Research Center for Cancer Prevention and Screening, National Cancer Center, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan. tkobayas@ncc.go.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Takushi
authors.initials: T
authors.lastname: Gotohda
authors.forename: Katsunori
authors.initials: K
authors.lastname: Tamakawa
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Ueda
authors.forename: Tadao
authors.initials: T
authors.lastname: Kakizoe
mesh_terms: D000818:Animals; D004574:Electromagnetic Fields; D005260:Female; D005743:Gastrectomy / Q000295:instrumentation* / Q000379:methods; D005753:Gastric Mucosa / Q000601:surgery*; D005773:Gastroscopy; D008280:Magnetics / Q000295:instrumentation*; D019060:Minimally Invasive Surgical Procedures; D013525:Surgical Instruments; D013552:Swine