Cerebral angiography is still widely used in the investigation
of aSAH and the characterization of ruptured cerebral
aneurysms. Although CTA is sometimes considered sufficient
on its own when an aneurysm will be treated with
surgical clipping,114 substantial controversy remains about
the ability of CTA to determine whether or not an aneurysm
is amenable to endovascular therapy.115–120 In 1 series,115
95.7% of patients with aSAH were referred for treatment on
the basis of CTA. In 4.4% of patients, CTA did not provide
enough information to determine the best treatment, and those
patients required DSA; 61.4% of patients were referred to
endovascular treatment on the basis of CTA; and successful coiling was achieved in 92.6%