Improved diagnosis of actively bleeding aneurysm on CT angiography using delayed CT images

Computed tomographic angiography (CTA) is being increasingly utilized in the non-invasive diagnosis of aneurysmal subarachnoid hemorrhage (SAH). There are emerging reports of diagnosis of active aneurysmal bleeding on CTA, furthering our understanding of imaging features of active extravasation on cross-sectional studies. We demonstrate imaging characteristics of two such cases of active contrast extravasation from intracranial aneurysms. Additionally, we demonstrate that delayed CT images greatly improve the confidence of this diagnosis by demonstrating pooling of contrast in the subarachnoid space. Prompt recognition and management can improve prognosis of this potentially lethal condition.