Ahn et al reported the Subarachnoid Hemorrhage Early Brain Edema Score (original SEBES, also SHEBES) for evaluating a patient with subarachnoid hemorrhage. The authors are from University of Texas Health Science Center Houson and University of Ulsan.

Patient selection: spontaneous aneurysmal subarachnoid hemorrhage


Exam: brain CT scan within 24 hours of onset


Sites for evaluation:

(1) level of the insular cortex showing the thalamus and basal ganglion above the basal cistern

(2) level of the centrum semiovale above the level of the lateral ventricle




visible (no effacement)


not visible (effacement)



Each side is examined separately, for a total of 4 locations.


total score =

= SUM(points for the 4 locations)



• minimum score: 0

• maximum score: 4

• A score >=3 indicates severe cerebral edema (high-grade SEBES). This is associated with delayed cerebral ischemia.

• A score <= 2 indicates low-grade cerebral edema (low-grade SEBES).

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