title: MR imaging of solitary fibrous tumors in the head and neck.
abstract: OBJECTIVE
  Solitary fibrous tumor (SFT) is a very rare tumor. The purpose of this study is to determine the MR imaging features of SFT in the intracranial and extracranial head and neck regions.
  
  
  METHODS
  We retrospectively reviewed six MR images and two CT images of six histologically proven cases of SFT that occurred in four men and two women, and their ages ranged from 46 to 59 years. These imaging findings were correlated with the microscopic findings of their surgical specimens.
  
  
  RESULTS
  Six SFTs arose in the meninges (the petrous ridge and the pituitary fossa), the parotid gland, the parapharyngeal space, the buccal space and the maxillary sinus. On the MR images, SFTs in the intracranial and extracranial head and neck regions were mostly isointense to the muscle on the T1-weighted images, they were hyperintense on the T2-weighted images and they all had intense enhancement. On the T1- and T2-weighted images, hypointense lines were observed within in five SFTs. On the CT images, the SFTs were hypodense to the muscle on the unenhanced images and they were heterogeneously enhanced on the contrast-enhanced images. An exceptional case of pituitary SFT was hypointense on the T2-weighted images and it was hyperdense on the unenhanced CT images, which correlated with the increased collagenous component and the cellular compactness.
  
  
  CONCLUSIONS
  The imaging features of SFT are nonspecific; however, SFT should be included in the differential diagnosis of masses involving the intracranial and extracranial head and neck regions.
authors.affiliation: Department of Radiology, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University.
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Ho Kyu
authors.initials: HK
authors.lastname: Lee
authors.forename: Jeong Jin
authors.initials: JJ
authors.lastname: Seo
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Shin
authors.forename: Ae Kyung
authors.initials: AK
authors.lastname: Jeong
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Kyung Ja
authors.initials: KJ
authors.lastname: Cho
mesh_terms: D000328:Adult; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology; D014057:Tomography, X-Ray Computed