title: The use of cone beam computed tomography in the postoperative assessment of orbital wall fracture reconstruction.
abstract: OBJECTIVE
  Computed tomography (CT) is currently the standard in postoperative evaluation of orbital wall fracture reconstruction, but cone beam computed tomography (CBCT) offers potential advantages including reduced radiation dose and cost. The purpose of this study is to examine objectively the image quality of CBCT in the postoperative evaluation of orbital fracture reconstruction, its radiation dose, and cost compared with CT.
  
  
  METHODS
  Four consecutive patients with orbital wall fractures in whom surgery was indicated underwent orbital reconstruction with radio-opaque grafts (bone, titanium-reinforced polyethylene, and titanium plate) and were assessed postoperatively with orbital CBCT. CBCT was evaluated for its ability to provide objective information regarding the adequacy of orbital reconstruction, radiation dose, and cost.
  
  
  RESULTS
  In all patients, CBCT was feasible and provided hard tissue image quality comparable to CT with significantly reduced radiation dose and cost. However, it has poorer soft tissue resolution, which limits its ability to identify the extraocular muscles, their relationship to the reconstructive graft, and potential muscle entrapment.
  
  
  CONCLUSIONS
  CBCT is a viable alternative to CT in the routine postoperative evaluation of orbital fracture reconstruction. However, in the patient who develops gaze restriction postoperatively, conventional CT is preferred over CBCT for its superior soft tissue resolution to exclude extraocular muscle entrapment.
authors.affiliation: From the *Departments of Oral and Maxillofacial Surgery and †Radiology, Royal Adelaide Hospital, Adelaide, Australia.
authors.forename: Kim
authors.initials: K
authors.lastname: Tsao
authors.forename: Andrew
authors.initials: A
authors.lastname: Cheng
authors.forename: Alastair
authors.initials: A
authors.lastname: Goss
authors.forename: David
authors.initials: D
authors.lastname: Donovan
mesh_terms: D000328:Adult; D000368:Aged; D054893:Cone-Beam Computed Tomography / Q000191:economics / Q000379:methods* / Q000592:standards; D005240:Feasibility Studies; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008297:Male; D008875:Middle Aged; D009917:Orbital Fractures / Q000000981:diagnostic imaging* / Q000601:surgery; D011184:Postoperative Period; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult