title: Validation and accuracy of intraoperative CT scan using the Philips AlluraXper FD20 angiography suite for assessment of spinal instrumentation.
abstract: BACKGROUND
  With the concept of the hybrid operating room gaining popularity, the authors adapted a hybrid angiographic suite with intraoperative computed tomography (iCT) to evaluate accuracy of pedicle screw placement in spinal fusion. This retrospective review examines how well iCT detected extrapedicular screw violation, to then allow repositioning and potentially avoid revision surgery.
  
  
  METHODS
  A total of 36 consecutive patients underwent pedicle screw placement in posterior cervical, thoracic, and lumbosacral spinal fusions. All patients underwent iCT in the Philips AlluraXper FD20 angiography suite in the lumbar spine XperCT mode and postoperative conventional computed tomography (CT) scanning. Primary endpoints included the sensitivity and specificity of iCT in detecting pedicular violation characterized as minor, moderate, or severe when compared with postoperative CT. Secondary endpoint included the incidence of replaced screws during surgery and number of revision surgeries.
  
  
  RESULTS
  Of 241 screws placed in 16 males and 20 females, iCT detected severe pedicle violation in 25 screws (10.4%); 16 screws were then repositioned during surgery. Sensitivity and specificity of iCT to detect severe screw malposition were 92.3% and 99.1%, respectively. No revision surgeries were performed in this series.
  
  
  CONCLUSIONS
  In our series, iCT had high sensitivity and specificity in detecting severe screw malposition. As a valuable adjunct for intraoperative assessment of pedicle screw position, immediate intraoperative correction of misplaced screws then eliminated any revision surgery for our patients.
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Edin
authors.initials: E
authors.lastname: Nevzati
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Javier
authors.initials: J
authors.lastname: Fandino
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Bawarjan
authors.initials: B
authors.lastname: Schatlo
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Michel
authors.initials: M
authors.lastname: Heimberg
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Serge
authors.initials: S
authors.lastname: Marbacher
authors.affiliation: b Division of Neuroradiology, Department of Radiology , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Luca
authors.initials: L
authors.lastname: Remonda
authors.affiliation: a Department of Neurosurgery , Kantonsspital Aarau , Aarau , Switzerland.
authors.forename: Ali-Reza
authors.initials: AR
authors.lastname: Fathi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods*; D001863:Bone Screws; D005260:Female; D006801:Humans; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D012086:Reoperation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013123:Spinal Fusion / Q000379:methods*; D013131:Spine / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Hybrid OR; intra-operative CT; pedicle screw; spine instrumentation; spine surgery