title: Utility of the LevelCheck Algorithm for Decision Support in Vertebral Localization.
abstract: METHODS
  An automatic radiographic labeling algorithm called "LevelCheck" was analyzed as a means of decision support for target localization in spine surgery. The potential clinical utility and scenarios in which LevelCheck is likely to be the most beneficial were assessed in a retrospective clinical data set (398 cases) in terms of expert consensus from a multi-reader study (three spine surgeons).
  
  
  OBJECTIVE
  The aim of this study was to evaluate the potential utility of the LevelCheck algorithm for vertebrae localization.
  
  
  BACKGROUND
  Three hundred ninety-eight intraoperative radiographs and 178 preoperative computed tomographic (CT) images for patients undergoing spine surgery in cervical, thoracic, lumbar regions.
  
  
  METHODS
  Vertebral labels annotated in preoperative CT image were overlaid on intraoperative radiographs via 3D-2D registration. Three spine surgeons assessed the radiographs and LevelCheck labeling according to a questionnaire evaluating performance, utility, and suitability to surgical workflow. Geometric accuracy and registration run time were measured for each case.
  
  
  RESULTS
  LevelCheck was judged to be helpful in 42.2% of the cases (168/398), to improve confidence in 30.6% of the cases (122/398), and in no case diminished performance (0/398), supporting its potential as an independent check and assistant to decision support in spine surgery. The clinical contexts for which the method was judged most likely to be beneficial included the following scenarios: images with a lack of conspicuous anatomical landmarks; level counting across long spine segments; vertebrae obscured by other anatomy (e.g., shoulders); poor radiographic image quality; and anatomical variations/abnormalities. The method demonstrated 100% geometric accuracy (i.e., overlaid labels within the correct vertebral level in all cases) and did not introduce ambiguity in image interpretation.
  
  
  CONCLUSIONS
  LevelCheck is a potentially useful means of decision support in vertebral level localization in spine surgery.
  
  
  METHODS
  N/A.
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Tharindu
authors.initials: T
authors.lastname: De Silva
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Sheng-Fu L
authors.initials: SL
authors.lastname: Lo
authors.affiliation: Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Nafi
authors.initials: N
authors.lastname: Aygun
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Aghion
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Akwasi
authors.initials: A
authors.lastname: Boah
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Rory
authors.initials: R
authors.lastname: Petteys
authors.affiliation: Department of Computer Science, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Ali
authors.initials: A
authors.lastname: Uneri
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ketcha
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Yi
authors.affiliation: Siemens Healthcare, Erlangen, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Vogt
authors.affiliation: Siemens Healthcare, Erlangen, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Kleinszig
authors.affiliation: Siemens Healthcare, Erlangen, Germany.
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.affiliation: Siemens Healthcare, Erlangen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Weiten
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Xiaobu
authors.initials: X
authors.lastname: Ye
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Ali
authors.initials: A
authors.lastname: Bydon
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Sciubba
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Witham
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Wolinsky
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.|Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Department of Computer Science, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Siewerdsen
mesh_terms: D000465:Algorithms; D020000:Decision Support Systems, Clinical; D021621:Imaging, Three-Dimensional; D013131:Spine / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed