title: Intradural calcifying pseudoneoplasm of the neuraxis presenting as a cauda equina syndrome.
abstract: BACKGROUND
  Calcifying nonneoplastic pseudoneoplasms of the neuraxis (CAPNON) have been reported in 59 cases in literature, however, they rarely involve the spinal cord. Owing to the advances in immunohistochemical markers, their structure and origin are better understood now.
  
  
  METHODS
  We present the case of a 72-year-old female who had longstanding history of low back pain that exacerbated 20 days prior to the presentation to the emergency room with a frank cauda equina syndrome. The lumbar computed tomography scan showed a hyperdense lesion, suggestive of calcified tumor, whereas the magnetic resonance imaging revealed a hypointense lesion on theT1 and T2-weighted images, without contrast enhancement or edema on fluid-attenuated inversion recovery. She underwent an emergent L2-L4 laminectomy and L3-L4 discectomy with resection of L2 intradural tumor, following which she regained normal function.
  
  
  CONCLUSIONS
  A 72-year-old female presented with a cauda equina syndrome attributed to an L2 intradural CAPNON. Following gross total resection, the patient was neurologically intact.
authors.affiliation: Department of Neurology, University of São Paulo, São Paulo, Brazil.
authors.forename: Arthur J M
authors.initials: AJ
authors.lastname: Lopes
authors.affiliation: Department of Neurology, University of São Paulo, São Paulo, Brazil.
authors.forename: Roger S
authors.initials: RS
authors.lastname: Brock
authors.affiliation: Department of Neurology, University of São Paulo, São Paulo, Brazil.
authors.forename: Thiago G
authors.initials: TG
authors.lastname: Martins
authors.affiliation: Department of Anatomic Pathology Division, University of São Paulo, São Paulo, Brazil.
authors.forename: Raphael S S
authors.initials: RS
authors.lastname: de Medeiro
authors.affiliation: Department of Anatomic Pathology Division, University of São Paulo, São Paulo, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Montezzo
authors.affiliation: Department of Neurology, University of São Paulo, São Paulo, Brazil.
authors.forename: Matheus F
authors.initials: MF
authors.lastname: de Oliveira
authors.affiliation: Department of Neurology, University of São Paulo, São Paulo, Brazil.
authors.forename: Manoel J
authors.initials: MJ
authors.lastname: Teixeira
keywords: Calcifying nonneoplastic pseudoneoplasms (CAPNON); differential diagnosis; intradural; neoplasm; spine