title: Fast fluid-attenuated inversion-recovery MR of intracranial infections.
abstract: OBJECTIVE
  To assess the usefulness of fast fluid-attenuated inversion-recovery (FLAIR) MR sequences in the diagnosis of intracranial infectious diseases.
  
  
  METHODS
  We compared fast FLAIR images with conventional spin-echo images (T1- and T2-weighted) obtained in 20 patients with infectious diseases (six with encephalitis, five with brain abscesses, three with meningitis, two with meningoencephalitis, two with Creutzfeldt-Jakob disease, one with epidural empyema, and one with cysticercosis). Two neuroradiologists independently reviewed the FLAIR images and compared them with the conventional spin-echo images, obtaining agreement in all patients.
  
  
  RESULTS
  FLAIR images of diagnostic quality were obtained in 18 patients. In two patients, FLAIR images were degraded by motion. Lesions in the patients with encephalitis and meningoencephalitis were better delineated on FLAIR images than on spin-echo images. FLAIR images clearly depicted lesions in the basal ganglia in both patients with Creutzfeldt-Jakob disease. In patients with brain abscess, meningitis, cysticercosis, and epidural empyema, FLAIR images provided no more information than conventional spin-echo images, and the lesions were seen better on postcontrast T1-weighted spin-echo images.
  
  
  CONCLUSIONS
  Fast FLAIR images showed pathologic changes in intracranial infectious diseases better than or as well as conventional T2- and proton density-weighted spin-echo sequences. However, postcontrast T1-weighted spin-echo sequences resulted in better visibility of abscess, meningitis, cysticercosis, and epidural empyema than did FLAIR images.
authors.affiliation: Department of Radiology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: S
authors.initials: S
authors.lastname: Inaoka
authors.forename: Y
authors.initials: Y
authors.lastname: Mizutani
authors.forename: J
authors.initials: J
authors.lastname: Hachiya
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016477:Artifacts; D001424:Bacterial Infections / Q000175:diagnosis*; D001921:Brain / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004578:Electron Spin Resonance Spectroscopy; D004660:Encephalitis / Q000175:diagnosis*; D018792:Encephalitis, Viral / Q000175:diagnosis; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity