The World Federation of Neurosurgical Societies (WFNS) Scale is a clinical grading system for aneurysmal subarachnoid hemorrhage (SAH). It standardizes how clinicians describe initial neurological severity using the Glasgow Coma Scale (GCS) plus the presence of a focal neurological deficit. WFNS grade strongly correlates with risks of complications (like delayed cerebral ischemia) and with overall outcomes, and it helps guide early management intensity and prognostication.
WFNS SAH Scale Calculator
Grades aneurysmal SAH severity using total GCS and focal neurological deficit (Original WFNS). Optional toggle for Modified WFNS.
m-WFNS assigns GCS 14 → Grade II and GCS 13 → Grade III regardless of deficit. For all other GCS values, grading matches original WFNS.
I: GCS 15, no deficit
II: GCS 13–14, no deficit
III: GCS 13–14, deficit present
IV: GCS 7–12 (± deficit)
V: GCS 3–6 (± deficit)
