title: Characteristic neuroimaging in patients with tumefactive demyelinating lesions exceeding 30 mm.
abstract: OBJECTIVE
  Features of tumefactive demyelinating lesion (TDL) on magnetic resonance imaging (MRI) can facilitate the differential diagnosis of TDL and neoplastic lesions, but vary considerably among patients. The larger TDL grows, the more difficult it becomes to differentiate TDL from neoplastic lesions. The purpose of this study was to elucidate typical MRI features in 12 patients with large TDL (>30 mm in diameter).
  
  
  METHODS
  We identified 12 patients with large TDL (six men, six women; age range 17-64 years, median age 27 years) and studied the clinical histories and the results of laboratory and various radiological studies in these patients. All cases of clinically definite multiple sclerosis were diagnosed in accordance with McDonald's revised criteria.
  
  
  RESULTS
  Common MRI features of large TDLs included variable degrees of mass effect (71%) and edema (100%), a T2 hypointense rim (79%), venular enhancement (57%), and peripheral restriction on diffusion-weighted images (50%). Ring enhancement (38%), open-ring enhancement (31%), or decreased N-acetylaspartate ratios on magnetic resonance spectroscopy (22%) were less frequently observed. Brain angiography demonstrated venous dilatations on and around the TDL.
  
  
  CONCLUSIONS
  The diagnosis of large TDL is challenging. Our findings suggest that multiple venous dilatations on and around TDLs on angiography can facilitate diagnosis.
authors.affiliation: Department of Neurology, Nara Medical University, Kashihara, Nara, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Kiriyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kataoka
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Taoka
authors.forename: Yasuyo
authors.initials: Y
authors.lastname: Tonomura
authors.forename: Mari
authors.initials: M
authors.lastname: Terashima
authors.forename: Masami
authors.initials: M
authors.lastname: Morikawa
authors.forename: Emi
authors.initials: E
authors.lastname: Tanizawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawahara
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Furiya
authors.forename: Kazuma
authors.initials: K
authors.lastname: Sugie
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Kichikawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ueno
mesh_terms: D000293:Adolescent; D000328:Adult; D001923:Brain Chemistry; D001927:Brain Diseases / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D003711:Demyelinating Diseases / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D004185:Disability Evaluation; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000473:pathology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA