title: Olfactory neuroblastoma: MR evaluation.
abstract: OBJECTIVE
  To evaluate MR in the diagnosis and staging of olfactory neuroblastoma.
  
  
  METHODS
  Five patients with histologically proved olfactory neuroblastomas were studied by MR. Four also had CT scans.
  
  
  RESULTS
  The extent of disease delineated by MR agreed with surgical findings and surgical staging of the tumor in all five patients. All cases of olfactory neuroblastomas originated in the nasal cavity and involved the ethmoid sinuses. In three of the five cases, the tumors extended to the anterior skull base. In one case MR correctly suggested skull base involvement missed on CT. Lesions were isointense to hyperintense with muscle on T1-weighted scans. Compared with fat on T2-weighted scans, olfactory neuroblastomas were variable in signal intensity. Enhancement was minimal to moderate in all cases.
  
  
  CONCLUSIONS
  In the evaluation of olfactory neuroblastoma, MR is most useful in delineating the extent of the tumor and may be more accurate than CT. However, the signal intensity characteristics of olfactory neuroblastomas may overlap other tumors.
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, Hospital of the University of Pennsylvania, Philadelphia 19104.
authors.forename: C
authors.initials: C
authors.lastname: Li
authors.forename: D M
authors.initials: DM
authors.lastname: Yousem
authors.forename: R E
authors.initials: RE
authors.lastname: Hayden
authors.forename: R L
authors.initials: RL
authors.lastname: Doty
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018304:Esthesioneuroblastoma, Olfactory / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000000981:diagnostic imaging; D009669:Nose Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed