title: Reversibility of brain morphology after shunt operations and preoperative clinical symptoms in patients with idiopathic normal pressure hydrocephalus.
abstract: OBJECTIVE
  Brain deformations might prevent clinical symptoms from worsening in patients with idiopathic normal pressure hydrocephalus (iNPH). We investigated the relationship between reversibility of brain morphology after shunt operations and preoperative clinical symptoms in iNPH patients.
  
  
  METHODS
  Using head magnetic resonance images with voxel-based morphometry, we measured the cerebrospinal fluid volume in the combined areas of the lateral and third ventricles and Sylvian fissure (the volume of the ventricles and Sylvian fissure (vVS)) and the volume of the subarachnoid space at high convexity and midline areas (vHCM) before and 1 year after lumboperitoneal shunt operations in 12 patients with shunt-responsive iNPH. We used the ratio of normalized vVS to normalized vHCM (nvVS/nvHCM) as an index of the severity of the brain deformation. The degree of reversibility of the brain morphology after the shunt operation was defined as the change ratio of the preoperative nvVS/nvHCM to the postoperative nvVS/nvHCM (CR-nvVS/nvHCM). Higher CR-nvVS/nvHCM values indicated more improvement in the brain deformation. In addition, we rated the severity of the white matter lesions on the preoperative magnetic resonance images based on the Fazekas scale. Dependency in activities of daily living, gait and cognition were evaluated before and 1 year after the shunt operations.
  
  
  RESULTS
  After the shunt operations, the nvVS/nvHCM and nvVS decreased significantly, and nvHCM increased significantly. The CR-nvVS/nvHCM negatively correlated with the preoperative severity of dependency in activities of daily living, gait and cognitive impairments. The CR-nvVS/nvHCM negatively correlated with the Fazekas scale, but not with age, duration of the disease and cerebrospinal fluid pressure.
  
  
  CONCLUSIONS
  Reversibility of brain morphology, which varied among iNPH patients, would prevent clinical symptoms from worsening in iNPH patients. The presence of white matter lesions reduced the degree of reversibility of the brain deformations in iNPH patients.
authors.affiliation: Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Tamiki
authors.initials: T
authors.lastname: Wada
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kazui
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamamoto
authors.forename: Keiko
authors.initials: K
authors.lastname: Nomura
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Sugiyama
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Yoshida
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoshiyama
authors.forename: Fumio
authors.initials: F
authors.lastname: Yamashita
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Kishima
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yoshimine
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takeda
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D002552:Cerebral Ventricles / Q000473:pathology / Q000601:surgery*; D015170:Cerebrospinal Fluid Pressure / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D005260:Female; D005684:Gait; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011184:Postoperative Period; D057234:Preoperative Period; D012720:Severity of Illness Index; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt