title: Reliability of intraoperative navigation in restoring normal orbital dimensions.
abstract: OBJECTIVE
  To assess the reliability and effectiveness of intraoperative navigation in restoring normal orbital and globe dimensions in traumatic and postablative orbital defects.
  
  
  METHODS
  To address the research purpose, the investigators initiated a retrospective cohort study and enrolled a sample of subjects that underwent primary or secondary reconstruction for unilateral orbital deformities secondary to traumatic injury or tumor surgery during the study enrollment period. Using computed tomographic datasets, pre- and postoperative orbital volume and globe projection were measured using Analyze software (Mayo Clinic Biomedical Imaging Resource, Rochester, MN). Intraclass correlation coefficient (ICC) was used to evaluate the reliability between preoperative unaffected orbit and the postoperative affected orbital and globe dimensions. A matched pairs t test was used to assess the difference in pre- and postoperative orbital volume and globe projection.
  
  
  RESULTS
  The sample was composed of 23 subjects that underwent orbital reconstruction secondary to traumatic of postablative defects. There was a linear and reliable relationship between preoperative unaffected and postoperative affected orbital volumes (ICC, 0.67; 95% CI, 0.37 to 0.86), and preoperative unaffected and postoperative affected globe projections was high (ICC, 0.87; 95% CI, 0.69 to 0.94). There was a significant difference in pre- and postoperative mean orbital volume (30.6 vs 25.5 cm(3), P ≤ 0.001), and pre- and postoperative globe projection (51.2 vs 53.6 mm, P ≤ 0.001).
  
  
  CONCLUSIONS
  The results of this study suggest that intraoperative navigation-assisted orbital reconstruction is reliable in restoring orbital volume and globe projection to pretraumatic and preablative conditions.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Markiewicz
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Dierks
authors.forename: Bryce E
authors.initials: BE
authors.lastname: Potter
authors.forename: R Bryan
authors.initials: RB
authors.lastname: Bell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001672:Biocompatible Materials / Q000627:therapeutic use; D016025:Bone Transplantation; D015331:Cohort Studies; D005123:Eye / Q000033:anatomy & histology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008440:Maxillary Fractures / Q000601:surgery; D008875:Middle Aged; D009915:Orbit / Q000293:injuries / Q000601:surgery*; D009917:Orbital Fractures / Q000601:surgery; D009918:Orbital Neoplasms / Q000601:surgery; D009929:Organ Size; D019736:Prostheses and Implants; D019651:Plastic Surgery Procedures / Q000592:standards*; D012189:Retrospective Studies; D012887:Skull Fractures / Q000601:surgery; D012984:Software; D025321:Surgery, Computer-Assisted / Q000592:standards*; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult; D015051:Zygomatic Fractures / Q000601:surgery
chemical_list: D001672:Biocompatible Materials