Postbleed day 6 CTA of the COW. CTA = computed tomographic angiography and COW = circle of Willis. (A) Axial CTA image at the level of the pons displaying severe spasm of the basilar artery (white arrow). (B) Axial CTA image at the level of the mesencephalon displaying severe spasm of the right proximal middle cerebral artery (white arrow). (C) Three-dimensional reconstruction of the CTA displaying the COW. Of note is the severe spasm of the basilar artery trunk and the right middle cerebral artery and bilateral proximal anterior cerebral arteries.