title: Automatic determination of optimal linear drilling trajectories for cochlear access accounting for drill-positioning error.
abstract: BACKGROUND
  Cochlear implantation is a surgical procedure in which an electrode array is permanently implanted into the cochlea to stimulate the auditory nerve and allow deaf people to hear. Percutaneous cochlear access, a new minimally invasive implantation approach, requires drilling a single linear channel from the skull surface to the cochlea. The focus of this paper addresses a major challenge with this approach, which is the ability to determine, in a pre-operative CT, a safe and effective drilling trajectory.
  
  
  METHODS
  A measure of the safety and effectiveness of a given trajectory relative to sensitive structures is derived using a Monte Carlo approach. The drilling trajectory that maximizes this measure is found using an optimization algorithm.
  
  
  RESULTS
  In tests on 13 ears, the technique was shown to find approximately twice as many acceptable trajectories as those found manually by an experienced surgeon.
  
  
  CONCLUSIONS
  Using this method, safe trajectories can be automatically determined quickly and consistently.
authors.affiliation: Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN 37235, USA. jack.h.noble@vanderbilt.edu
authors.forename: Jack H
authors.initials: JH
authors.lastname: Noble
authors.forename: Omid
authors.initials: O
authors.lastname: Majdani
authors.forename: Robert F
authors.initials: RF
authors.lastname: Labadie
authors.forename: Benoit
authors.initials: B
authors.lastname: Dawant
authors.forename: J Michael
authors.initials: JM
authors.lastname: Fitzpatrick
mesh_terms: D001331:Automation; D003051:Cochlea / Q000033:anatomy & histology / Q000601:surgery*; D019929:Cochlear Implantation / Q000379:methods*; D003638:Deafness / Q000601:surgery; D004423:Ear / Q000033:anatomy & histology; D004566:Electrodes / Q000706:statistics & numerical data; D004867:Equipment Design; D006801:Humans; D056888:Patient Positioning; D011336:Probability; D012371:Robotics / Q000295:instrumentation / Q000379:methods; D012449:Safety; D013701:Temporal Bone / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
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