title: A novel pressure sensor with an optical system for coil embolization of intracranial aneurysms. Laboratory investigation.
abstract: OBJECTIVE
  In endovascular coil embolization for an intracranial aneurysm, the excessive pressure created during coil insertion into an aneurysm can cause a catastrophic rupture or dislodge a microcatheter tip from the aneurysm dome, resulting in insufficient embolization. Such undue mechanical pressure can only be subjectively detected by the subtle tactile feedback the surgeon experiences. Therefore, the authors of this study developed a new sensor device to measure the coil insertion pressure via an optical system.
  
  
  METHODS
  This novel sensor system consists of a hemostatic valve connected to the proximal end of a microcatheter (Y-connector). The sensor principle is based on an optical system composed of a light-emitting diode (LED) and a line sensor. The latter measures how much the coil-delivery wire slightly bends in response to the insertion pressure by detecting the wire shadow. This information is translated into a given force level. Experimental aneurysm embolization was performed using this optical sensor. A silicone aneurysm model and an in vivo model (porcine aneurysm model) were used in this study. Several surgeons manually performed the coil insertions. The sensor continuously monitored the mechanical force during the insertions.
  
  
  RESULTS
  The sensor adequately recorded the coil insertion pressure during embolization. The presence of the sensor did not hinder the embolization procedure in any way. During embolization in the silicone aneurysm model, a sinusoid pattern of pressure occurred, reflecting actual clinical experience. Similar results were obtained in the in vivo study.
  
  
  CONCLUSIONS
  This new sensor device adequately measures coil insertion pressure. This system provides potentially safer and more reliable aneurysm embolizations.
authors.affiliation: Department of Neurosurgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Matsubara
authors.forename: Shigeru
authors.initials: S
authors.lastname: Miyachi
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Nagano
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Ohshima
authors.forename: Osamu
authors.initials: O
authors.lastname: Hososhima
authors.forename: Takashi
authors.initials: T
authors.lastname: Izumi
authors.forename: Arihito
authors.initials: A
authors.lastname: Tsurumi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Wakabayashi
authors.forename: Masamichi
authors.initials: M
authors.lastname: Sakaguchi
authors.forename: Akihito
authors.initials: A
authors.lastname: Sano
authors.forename: Hideo
authors.initials: H
authors.lastname: Fujimoto
mesh_terms: D004582:Electronics, Medical; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D008953:Models, Anatomic; D011312:Pressure; D012828:Silicones; D014160:Transducers, Pressure
chemical_list: D012828:Silicones