title: Hyoid bone advancement for improving airway patency: cadaver study of a magnet-based system.
abstract: OBJECTIVE
  The goal of this study was to evaluate the effect of anterior forces applied to the hyoid bone on upper airway dimensions and airflow. The study also evaluated the feasibility of applying these forces using a novel magnet-based system.
  
  
  METHODS
  Human cadaver specimens.
  
  
  METHODS
  Surgical laboratory.
  
  
  METHODS
  Five fresh cadaveric specimens were evaluated using fluoroscopy and computed tomography to examine upper airway opening as well as an airflow model to examine upper airway collapse. Anteriorly directed force was applied to the hyoid bone directly using a wire and with a magnet-based system called the Magnap device. Direct application of force was examined with an axial load frame or suspended weights. The magnet-based system applied similar forces using an internal, implanted magnet secured to the hyoid bone and an external magnet housed within an orthotic brace.
  
  
  RESULTS
  A force of 2 N perpendicular to the neck skin advanced the hyoid 1 cm, opened the upper airway, and significantly improved airflow. The implanted magnet-based device generated similar forces, with similar effects on the upper airway.
  
  
  CONCLUSIONS
  Application of anterior force to the hyoid bone improved upper airway dimensions and airflow in the human cadaver model. These results justify additional study to evaluate the benefits of this magnet-based system as a possible treatment of upper airway obstruction.
authors: Department of Bioengineering, University of California San Francisco, San Francisco, California 94115, USA.
authors: Kathryn H
authors: KH
authors: Rosenbluth
authors: Dillon A
authors: DA
authors: Kwiat
authors: Michael R
authors: MR
authors: Harrison
authors: Eric J
authors: EJ
authors: Kezirian
mesh_terms: D000402:Airway Obstruction / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D000403:Airway Resistance; D002102:Cadaver; D005240:Feasibility Studies; D005471:Fluoroscopy; D006801:Humans; D006928:Hyoid Bone / Q000000981:diagnostic imaging* / Q000601:surgery*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D059346:Magnets; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods