title: Associations of intracranial pressure with brain biopsy, radiological findings, and shunt surgery outcome in patients with suspected idiopathic normal pressure hydrocephalus.
abstract: It remains unclear how intracranial pressure (ICP) measures are associated with brain biopsies and radiological markers. Here, we aim to investigate associations between ICP and radiological findings, brain biopsies, and shunt surgery outcome in patients with suspected idiopathic normal pressure hydrocephalus (iNPH).
  
  
  
  In this study, we retrospectively analyzed data from 73 patients admitted with suspected iNPH to Kuopio University Hospital. Of these patients, 71% underwent shunt surgery. The NPH registry included data on clinical and radiological examinations, 24-h intraventricular pressure monitoring, and frontal cortical biopsy.
  
  
  
  The mean ICP and mean ICP pulse wave amplitude were not associated with the shunt response. Aggregations of Alzheimer's disease (AD)-related proteins (amyloid-β, hyperphosphorylated tau) in frontal cortical biopsies were associated with a poor shunt response (P = 0.014). High mean ICP was associated with Evans' index (EI; P = 0.025), disproportional sylvian and suprasylvian subarachnoid spaces (P = 0.014), and focally dilated sulci (P = 0.047). Interestingly, a high pulse wave amplitude was associated with AD-related biopsy findings (P = 0.032), but the mean ICP was not associated with the brain biopsy. The ICP was not associated with medial temporal lobe atrophy, temporal horn widths, or white matter changes. ICP B waves were associated with less atrophy of the medial temporal lobe (P = 0.018) and more severe disproportionality between the sylvian and suprasylvian subarachnoid spaces (P = 0.001).
  
  
  
  The EI and disproportional sylvian and suprasylvian subarachnoid spaces were associated with mean ICP. Disproportionality was also associated with ICP B waves. These associations, although rather weak, with elevated ICP in 24-h measurements, support their value in iNPH diagnostics and suggest that these radiological markers are potentially related to the pathogenesis of iNPH. Interestingly, our results suggested that elevated pulse wave amplitude might be associated with brain amyloid accumulation.
authors.affiliation: Neurosurgery of NeuroCenter, Kuopio University Hospital and University of Eastern Finland, P.O. Box 100, 70029, Kuopio, Finland. mariako@student.uef.fi.
authors.forename: Maria
authors.initials: M
authors.lastname: Kojoukhova
authors.affiliation: Neurosurgery of NeuroCenter, Kuopio University Hospital and University of Eastern Finland, P.O. Box 100, 70029, Kuopio, Finland.
authors.forename: Krista-Irina
authors.initials: KI
authors.lastname: Vanha
authors.affiliation: Neurosurgery of NeuroCenter, Kuopio University Hospital and University of Eastern Finland, P.O. Box 100, 70029, Kuopio, Finland.
authors.forename: Matti
authors.initials: M
authors.lastname: Timonen
authors.affiliation: Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.|Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Koivisto
authors.affiliation: Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.|Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Ossi
authors.initials: O
authors.lastname: Nerg
authors.affiliation: Department of Pathology, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Jaana
authors.initials: J
authors.lastname: Rummukainen
authors.affiliation: Department of Pathology, Kuopio University Hospital, Kuopio, Finland.|Institute of Clinical Medicine-Pathology, University of Eastern Finland, Kuopio, Finland.
authors.forename: Tuomas
authors.initials: T
authors.lastname: Rauramaa
authors.affiliation: Department of Radiology, Kuopio University Hospital and University of Eastern Finland, Kuopio, Finland.
authors.forename: Ritva
authors.initials: R
authors.lastname: Vanninen
authors.affiliation: Neurosurgery of NeuroCenter, Kuopio University Hospital and University of Eastern Finland, P.O. Box 100, 70029, Kuopio, Finland.
authors.forename: Juha E
authors.initials: JE
authors.lastname: Jääskeläinen
authors.affiliation: Department of Radiology, Kuopio University Hospital and University of Eastern Finland, Kuopio, Finland.
authors.forename: Anna
authors.initials: A
authors.lastname: Sutela
authors.affiliation: Neurosurgery of NeuroCenter, Kuopio University Hospital and University of Eastern Finland, P.O. Box 100, 70029, Kuopio, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Leinonen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002557:Cerebrospinal Fluid Shunts / Q000379:methods*; D005260:Female; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D007427:Intracranial Pressure / Q000502:physiology*; D008297:Male; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies
keywords: Alzheimer’s disease; Brain biopsy; Idiopathic normal pressure hydrocephalus; Intracranial pressure; Radiology; Shunt