title: Ossification of the vascular pedicle in microsurgical fibular free flap reconstruction of the head and neck.
abstract: OBJECTIVE
  The fibular free flap, often used for osseous reconstruction following extirpation of head and neck malignancies, has been associated with heterotopic periosteal ossification. We aimed to determine the frequency and radiologic characteristics of this process and describe its clinical correlates.
  
  
  METHODS
  Surgical records for 2 years and neck imaging reports for 10 years were evaluated to identify patients with fibular free flap reconstruction and CT and/or PET/CT imaging available for review. The images were evaluated for the quality, type, and contour of ossification, and the reports were reviewed for associated clinical findings and radiologic impressions.
  
  
  RESULTS
  Of 32 patients with posttreatment CT or PET/CT imaging, ossification was evident in 16 patients (50%) as early as 1 month following fibular free flap reconstruction. In 8 patients, it mimicked a new bone; in 5, it appeared as linear attenuation; in 2, as multiple short segments; and in 1 patient, a mixed appearance was found. No associated FDG uptake was seen on PET/CT. On MR imaging, these findings were extremely subtle or not appreciable. In only 1 patient was new bone associated with symptoms.
  
  
  CONCLUSIONS
  Periosteal ossification of the vascular pedicle is commonly evident on CT following fibular free flap, even as early as 1 month after reconstruction, though the finding is not typically noted on imaging. While symptoms related to new bone are uncommon, they may mimic recurrent tumor. The location and pattern of ossification and the absence of a soft-tissue mass or FDG uptake are useful distinguishing imaging features.
authors.affiliation: From the Departments of Radiology and Biomedical Imaging (C.M.G.) Otolaryngology-Head and Neck Surgery (C.M.G., P.D.K.), University of California, San Francisco, San Francisco, California. christine.glastonbury@ucsf.edu.
authors.forename: C M
authors.initials: CM
authors.lastname: Glastonbury
authors.affiliation: Anatomic Pathology (A.v.Z.).
authors.forename: A
authors.initials: A
authors.lastname: van Zante
authors.affiliation: Otolaryngology-Head and Neck Surgery (C.M.G., P.D.K.), University of California, San Francisco, San Francisco, California.
authors.forename: P D
authors.initials: PD
authors.lastname: Knott
mesh_terms: D000328:Adult; D005260:Female; D005360:Fibula; D058752:Free Tissue Flaps / Q000009:adverse effects*; D006257:Head / Q000000981:diagnostic imaging; D006258:Head and Neck Neoplasms / Q000601:surgery*; D006801:Humans; D008297:Male; D009333:Neck / Q000000981:diagnostic imaging; D009999:Ossification, Heterotopic / Q000209:etiology / Q000473:pathology*; D019651:Plastic Surgery Procedures / Q000009:adverse effects* / Q000379:methods; D014057:Tomography, X-Ray Computed