title: Fetus-supporting flexible manipulator with balloon-type stabilizer for endoscopic intrauterine surgery.
abstract: BACKGROUND
  Minimally invasive endoscopic fetal surgery enables intrauterine intervention with reduced risk to the mother and fetus. A novel surgical manipulator is described for stabilizing the fetus and restraining it from floating free during endoscopic intrauterine surgery.
  
  
  METHODS
  We designed and fabricated a prototype fetus-supporting manipulator equipped with flexible joint and bending mechanisms and a soft balloon stabilizer. The flexible joint and bending mechanisms enable the stabilizer to reach the target sites within the confined space of the uterus under the guidance of an ultrasound device. The balloon stabilizer could be inserted into the uterus through a small incision.
  
  
  RESULTS
  The accuracy evaluation showed that the maximum error of the bending mechanism was as small as 7 mm and the standard deviation of the joint mechanism was just 1.6 degrees. In the experiments using a fetus model, the manipulator could be well controlled with guidance from ultrasound images and its bending mechanism with the balloon stabilizer could be clearly visualized while stabilizing the fetus model.
  
  
  CONCLUSIONS
  The manipulator has the potential to be used in minimally invasive intrauterine surgery, although further improvements and experiments remain to be carried out.
authors.affiliation: Graduate School of Engineering, The University of Tokyo, Japan. liao@bmpe.t.u-tokyo.ac.jp
authors.forename: Hongen
authors.initials: H
authors.lastname: Liao
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Suzuki
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Matsumiya
authors.forename: Ken
authors.initials: K
authors.lastname: Masamune
authors.forename: Takeyoshi
authors.initials: T
authors.lastname: Dohi
authors.forename: Toshio
authors.initials: T
authors.lastname: Chiba
mesh_terms: D002404:Catheterization / Q000295:instrumentation / Q000379:methods; D004622:Embryo, Mammalian / Q000000981:diagnostic imaging* / Q000601:surgery*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020669:Fetoscopes; D005332:Fetoscopy / Q000379:methods; D006801:Humans; D007103:Immobilization / Q000295:instrumentation* / Q000379:methods; D008591:Meningomyelocele / Q000196:embryology / Q000601:surgery*; D012371:Robotics / Q000295:instrumentation*; D025321:Surgery, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D014463:Ultrasonography