title: [CT and MRI and clinical study of chordoma in the skull base].
abstract: OBJECTIVE
  To investigate the diagnostic features of CT and MRI in chordoma of the skull base (CSB) and to estimate their value of clinical application.
  
  
  METHODS
  Sixteen patients with CSB were performed CT and MRI examinations of the head, and 13 patients with nasopharyngeal carcinoma (NPC) and 11 patients with pituitary adenoma (PA) which invaded the skull base were selected as control. In addition, 7 cases of chordoma were performed multiple planar reconstruction (MPR) of MRI.
  
  
  RESULTS
  MRI was superior to CT in depicting the location and the extent of CSB. The bone destruction at mid-line skull base was demonstrated equally well on both CT and MRI. Based on the location of the tumor displayed on MRI, the CSB could be classified into selloclival, nasopharyngeal, and occipito-temperal types. The T2 weight imaging(T2WI) signal intensity of chordoma was significantly higher than those of NPC and PA (P < 0.01). On MPR images of MRI, oppressed and displaced optic nerves caused by chordoma were noted in 3 cases and encased optic nerves in 4 cases, encased abducent nerves in 7 cases with abducent paralysis and mildly oppressed oculomotor nerves in 3 cases.
  
  
  CONCLUSIONS
  The extremely high T2WI signal intensity is the characteristic of MRI finding in CSB and has great differential value for the tumors of the skull base. The MPR of MRI plays an important role in the surgical treatment for these tumors.
authors.affiliation: Department of Radiology, First Affiliated Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou 510080, China.
authors.forename: B
authors.initials: B
authors.lastname: Jiang
authors.forename: Q
authors.initials: Q
authors.lastname: Meng
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000328:Adult; D002817:Chordoma / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis; D010911:Pituitary Neoplasms / Q000175:diagnosis; D019292:Skull Base Neoplasms / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed / Q000379:methods