title: Apoplectic presentation of a cauda equina paraganglioma.
abstract: BACKGROUND
  Cauda equina paragangliomas (CEPs) are rare spinal tumors that are mostly misdiagnosed preoperatively as ependymomas or schwannomas on magnetic resonance imaging (MRI). Clinically, they usually present with the gradual onset of back pain and radiculopathy rather than an acute cauda equina syndrome.
  
  
  METHODS
  A 36-year-old female presented with an acute flaccid paraparesis/cauda equina syndrome. Based upon MRI studies, the predominant differential diagnoses included ependymoma or schwannoma. The intraoperative findings revealed an acute intralesional hemorrhage or apoplexy, responsible for the acute clinical deterioration. Histopathology and immunohistochemistry (IHC) revealed that the tumor was a paraganglioma.
  
  
  CONCLUSIONS
  CEPs commonly present with mild symptoms and signs rather than the acute-onset of a flaccid paraparesis/cauda equina syndrome as seen in this case. Here, the authors review the radiological and histopathological characteristics of CEP and emphasize the role of IHC in differentiating "CEP" from the more common ependymomas.
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: M N
authors.initials: MN
authors.lastname: Nagarjun
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: Amey R
authors.initials: AR
authors.lastname: Savardekar
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: Kislay
authors.initials: K
authors.lastname: Kishore
authors.affiliation: Department of Neuropathology, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: Shilpa
authors.initials: S
authors.lastname: Rao
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: Nupur
authors.initials: N
authors.lastname: Pruthi
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neuroscience, Bengaluru, Karnataka, India.
authors.forename: Malla Bhaskar
authors.initials: MB
authors.lastname: Rao
keywords: Apoplexy in spinal tumors; cauda equina paraganglioma; intradural extramedullary spinal tumor; intralesional hemorrhage in spinal tumors; tumors of the filum terminale