title: Modified World Federation of Neurosurgical Societies subarachnoid hemorrhage grading system.
abstract: OBJECTIVE
  A modified World Federation of Neurosurgical Societies scale (m-WFNS scale) for aneurysmal subarachnoid hemorrhage (SAH) recently has been proposed, in which patients with Glasgow Coma Scale (GCS) scores of 14 are assigned to grade II and those with GCS scores of 13 are assigned to grade III regardless of the presence of neurologic deficits. The study objective was to evaluate outcome predictability of the m-WFNS scale in a large cohort.
  
  
  METHODS
  This was a multicenter prospective observational study conducted in Japan. A total of 1656 patients with SAH were registered during the 2.5-year study period, and the outcome predictability, using the Glasgow Outcome Scale (GOS) and modified Rankin Scale (mRS) scores at discharge and at 90 days after onset, was evaluated by comparing the m-WFNS with the original WFNS scale. We focused on whether significant differences in these scores were present between the neighboring grades.
  
  
  RESULTS
  In the m-WFNS scale, significant difference between any neighboring grades was observed both in the mean GOS and mRS scores at 90 days except between grades III/IV. However, differences were not significant between grades II/III and between grades III/IV in the original WFNS scale.
  
  
  CONCLUSIONS
  SAH-induced brain injury may be substantially severer in patients with GCS 13 than those with GCS 14, which may explain why grade III patients faired significantly worse than grade II patients by the modified WFNS scale. Although further validation is necessary, the m-WFNS scale has a potential of providing neurosurgeons with simpler and more reliable prognostication of patients with SAH.
authors.affiliation: WFNS Cerebrovascular Diseases and Therapy Committee. Electronic address: hsano@white-jack.jp.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Sano
authors.affiliation: WFNS Cerebrovascular Diseases and Therapy Committee.
authors.forename: Akira
authors.initials: A
authors.lastname: Satoh
authors.affiliation: WFNS Cerebrovascular Diseases and Therapy Committee.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Murayama
authors.affiliation: WFNS Cerebrovascular Diseases and Therapy Committee.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Biostatistics and Clinical Epidemiology, University of Toyama Graduate School of Medicine and Pharmaceutical Sciences, Toyama-shi, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Origasa
authors.affiliation: Department of Neurosurgery, Fujita Health University School of Medicine, Toyoake, Japan.
authors.forename: Joji
authors.initials: J
authors.lastname: Inamasu
authors.affiliation: Department of Neurosurgery, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Nouri
authors.affiliation: Department of Neurosurgery, COMS Bharatpur, Bharatpur, Nepal.
authors.forename: Iype
authors.initials: I
authors.lastname: Cherian
authors.affiliation: Science Council, Japan Neurosurgical Society, Tokyo, Japan.
authors.forename: Nobuto
authors.initials: N
authors.lastname: Saito
mesh_terms: D000368:Aged; D015331:Cohort Studies; D004185:Disability Evaluation; D005260:Female; D015600:Glasgow Coma Scale; D023261:Glasgow Outcome Scale; D006801:Humans; D008297:Male; D008875:Middle Aged; D009493:Neurosurgery / Q000592:standards*; D019635:Neurosurgical Procedures / Q000592:standards*; D018458:Persistent Vegetative State / Q000453:epidemiology; D011446:Prospective Studies; D015203:Reproducibility of Results; D013345:Subarachnoid Hemorrhage / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome
keywords: Glasgow Coma Scale; Modified Rankin Scale; Outcomes; Subarachnoid hemorrhage; World Federation of Neurosurgical Societies