title: Perfusion and spectroscopy magnetic resonance imaging in a case of lymphocytic vasculitis mimicking brain tumor.
abstract: BACKGROUND
  Lymphocytic vasculitis of the central nervous system is an uncommon subtype of primary angiitis of the central nervous system (PACNS) - a rare inflammatory disorder affecting parenchymal and leptomeningeal arteries and veins.
  
  
  METHODS
  Establishing diagnosis on the basis of neuroimaging only is difficult, as it can mimic a brain tumor. Thus, histological diagnosis is essential for appropriate management. We present a case of biopsy-proven lymphocytic vasculitis mimicking a brain tumor on neuroimaging that was subsequently successfully treated with steroid therapy. We also discuss the findings in perfusion MR (PWI) and MR spectroscopy (MRS).
  
  
  CONCLUSIONS
  Regional hypoperfusion on PWI and elevation of glutamate and glutamine levels on MRS (without associated typical tumor spectra) are common findings in inflammatory disorders, including PACNS, and can be useful in differential diagnosis with tumors.
authors.affiliation: Neuroradiology Unit, Department of Neuroscience, "G. Rummo" Hospital, Benevento, Italy.
authors.forename: Carmine Franco
authors.initials: CF
authors.lastname: Muccio
authors.forename: Arturo
authors.initials: A
authors.lastname: Di Blasi
authors.forename: Gennaro
authors.initials: G
authors.lastname: Esposito
authors.forename: Luca
authors.initials: L
authors.lastname: Brunese
authors.forename: Felice
authors.initials: F
authors.lastname: D'Arco
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Caranci
keywords: brain tumor diagnostics; diffusion weighted imaging; magnetic resonance imaging (MRI); perfusion weighted imaging; primary angiitis of central nervous system (PACNS); proton magnetic resonance spectroscopy (1H MRS)