Rebleeding of aneurysmal subarachnoid hemorrhage in computed tomography angiography: risk factor, rebleeding...

For patients with subarachnoid hemorrhage (SAH), computed tomography angiography (CTA) has been the first imaging modality for aneurysm detection. We evaluate the rate, time distribution, risk factors, and clinical outcome of aneurysmal rebleeding by CTA findings.

Consecutive patients with SAH presenting to our hospital, a tertiary care hospital, were retrospectively included. We reviewed images for all patients receiving an initial noncontrast computed tomography scan and further CTA for nontraumatic SAH surveillance with focus on rebleeding evidence.

A total of 12 patients with early aneurysmal rebleeding (12/110 patients [10.9%]) within 6 hours after emergency room arrival were found with dismal outcome (50% mortality) and 3 rebleeding patterns: pattern 1 of rapid active bleeding with contrast extravasation, pattern 2 of slow active bleeding with contrast leakage in the delayed venous phase, and pattern 3 of hematoma enlargement. The risk factor and poor prognostic sign include larger aneurysm diameter (≧7 mm) and contrast extravasation during CTA.

Rebleeding rate of aneurysmal SAH in the hyperacute stage at less than 6 hours is 10.9% with poor prognosis in this study, especially in patients with active bleeding demonstrated in CTA.