Does including neck CTA in work-up of suspected intracranial hemorrhage add value?

PURPOSE: Neck CT angiography (CTA) is frequently performed in conjunction with head CTA in patients presenting with clinical signs and symptoms concerning for acute intracranial hemorrhage, despite relatively low appropriateness (ACR Appropriateness Criteria 2-6). This decision is sometimes justified by suggesting that CTA neck findings are useful in planning subsequent catheter angiography.

METHODS: We investigated the value of neck CTA in patients with suspected acute intracranial hemorrhage by reviewing 220 head and neck CTAs performed in our emergency room over a 24-month period for the indication of hemorrhage or headache. Images were reviewed by two neurointerventionalists to address the value of the neck CTA for planning catheter angiography.

RESULTS: Findings helpful for performing catheter angiography were observed on neck CTA in 22% (Cohen kappa 0.65), and included anatomical arch variants such as a bovine arch, direct vertebral artery arch origin, and aberrant subclavian artery. However, findings that might substantially prolong angiography for more than 10 min if unknown occurred in 5% (Cohen kappa 0.69). Incidental findings prompting additional imaging or significant clinical action occurred in 20%. Subarachnoid hemorrhage on noncontrast head CT was strongly associated with a need for subsequent angiography.

CONCLUSIONS: Although CTA neck can provide helpful information for planning catheter angiography, it rarely uncovers findings that would significantly prolong the procedure if unknown. Neck CTA is therefore only recommended in patients with a confirmed intracranial hemorrhage in a pattern consistent with aneurysm or arteriovenous shunt.