title: Newly developed electromagnetic tracked flexible neuroendoscope.
abstract: Flexible endoscopes can be used in areas that are difficult to approach using rigid endoscopes. No current real-time navigation systems identify the tip of the flexible neuroendoscope. We have developed a flexible neuroendoscope mounted with a magnetic field sensor tip position-tracking system and evaluated the accuracy of this magnetic field neuronavigation system. Based on an existing flexible neuroendoscope, we created a prototype with a built-in magnetic field sensor in the tip. A magnetic field measurement device provides a magnetic field with a working volume of 500 × 500 × 500 mm in front of the device. The device consists of a flat field generator that creates a pulsed magnetic field, connected to a system control unit that interfaces with a computer. The magnetic field sensor (1.8 × 9 mm) was sealed in a site 0.9 mm from the endoscope tip. Accuracy of neuroendoscope tracking was measured using a three-dimensional coordinate-measuring machine that measures the position of objects along 3 axes, with an error of about 3 µm. The accuracy for this neuroendoscope with built-in magnetic field sensor was root mean square error of 1.2 mm and standard deviation of 0.5 mm. This magnetic field neuronavigation system enables real-time tracking of the tip of the flexible neuroendoscope. Application of this flexible neuroendoscope to intraoperative navigation appears promising, and may provide new advantages for minimally invasive endoscopic surgery.
authors.affiliation: Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Atsumi
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Matsumae
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hirayama
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Sato
authors.forename: Hideaki
authors.initials: H
authors.lastname: Shigematsu
authors.forename: Go
authors.initials: G
authors.lastname: Inoue
authors.forename: Jun
authors.initials: J
authors.lastname: Nishiyama
authors.forename: Michitsura
authors.initials: M
authors.lastname: Yoshiyama
authors.forename: Jiro
authors.initials: J
authors.lastname: Tominaga
mesh_terms: D004574:Electromagnetic Fields; D004724:Endoscopy / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D044582:Neuroendoscopes / Q000592:standards* / Q000639:trends; D038361:Neuronavigation / Q000295:instrumentation* / Q000379:methods; D019635:Neurosurgical Procedures / Q000295:instrumentation* / Q000379:methods