title: Quantitative Measurement of CSF in Patients with Spontaneous Intracranial Hypotension.
abstract: OBJECTIVE
  CSF hypovolemia is a core feature of spontaneous intracranial hypotension. Spontaneous intracranial hypotension is characterized by orthostatic headache and radiologic manifestations, including CSF along the neural sleeves, diffuse pachymeningeal enhancement, and/or venous engorgement. However, these characteristics are only qualitative. Quantifying intraspinal CSF volumes could improve spontaneous intracranial hypotension diagnosis and evaluation of hypovolemic statuses in patients with spontaneous intracranial hypotension. The purpose of this study was to compare intraspinal CSF volumes across spontaneous intracranial hypotension stages and to test the clinical applicability of these measures.
  
  
  METHODS
  A cohort of 23 patients with spontaneous intracranial hypotension and 32 healthy controls was subjected to brain MR imaging and MR myelography with 1.5T imaging. An automatic threshold-based segmentation method was used to calculate intraspinal CSF volumes at initial hospitalization (spontaneous intracranial hypotension-initial), partial improvement (spontaneous intracranial hypotension-intermediate), and complete recovery (spontaneous intracranial hypotension-recovery) stages.
  
  
  RESULTS
  The mean intraspinal CSF volumes observed were the following: 95.31 mL for healthy controls, 72.31 mL for spontaneous intracranial hypotension-initial, 81.15 mL for spontaneous intracranial hypotension-intermediate, and 93.74 mL for spontaneous intracranial hypotension-recovery. Increased intraspinal CSF volumes were related to disease recovery (P< .001). The intraspinal CSF volumes of patients before complete recovery were significantly lower than those of healthy controls. With the estimated intradural CSF volumes as a reference, the intraspinal CSF volume percentage was lower in patients with spontaneous intracranial hypotension with venous engorgement than in those without it (P= .058).
  
  
  CONCLUSIONS
  With a threshold-based segmentation method, we found that spinal CSF hypovolemia is fundamentally related to spontaneous intracranial hypotension. Intraspinal CSF volumes could be a sensitive parameter for the evaluation of treatment response and follow-up monitoring in patients with spontaneous intracranial hypotension.
authors.affiliation: From the Departments of Radiology (H.-C.C., C.-H.C., C.C.-C.C., J.-W.C.).|Department of Medicine (H.-C.C.), National Yang-Ming University, Taipei, Taiwan.
authors.forename: H-C
authors.identifier: http://orcid.org/0000-0003-3544-5045
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Neurology (P.-L.C.), Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: P-L
authors.identifier: http://orcid.org/0000-0002-7254-0108
authors.initials: PL
authors.lastname: Chen
authors.affiliation: College of Medicine (Y.-H.T., J.-W.C.), China Medical University, Taichung, Taiwan.
authors.forename: Y-H
authors.identifier: http://orcid.org/0000-0002-0215-9440
authors.initials: YH
authors.lastname: Tsai
authors.affiliation: From the Departments of Radiology (H.-C.C., C.-H.C., C.C.-C.C., J.-W.C.).
authors.forename: C-H
authors.identifier: http://orcid.org/0000-0002-8856-4171
authors.initials: CH
authors.lastname: Chen
authors.affiliation: From the Departments of Radiology (H.-C.C., C.-H.C., C.C.-C.C., J.-W.C.).
authors.forename: C C-C
authors.identifier: http://orcid.org/0000-0002-3385-9466
authors.initials: CC
authors.lastname: Chen
authors.affiliation: From the Departments of Radiology (H.-C.C., C.-H.C., C.C.-C.C., J.-W.C.) hubt@vghtc.gov.tw.|College of Medicine (Y.-H.T., J.-W.C.), China Medical University, Taichung, Taiwan.
authors.forename: J-W
authors.identifier: http://orcid.org/0000-0002-2515-751X
authors.initials: JW
authors.lastname: Chai
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D019585:Intracranial Hypotension / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009192:Myelography / Q000379:methods