Involvement of the intracranial circulation in giant cell arteritis

OBJECTIVE: Giant cell arteritis (GCA) is the most common primary vasculitis affecting the elderly population. GCA preferentially involves the extracranial branches of the carotid artery; intracranial vasculitis is thought to be a rare occurrence. This study determined the prevalence of intracranial vasculitis in a large series of patients evaluated for GCA and describes the clinical presentation of such cases. DESIGN: Retrospective chart review using a prospective database. When possible, subjects underwent high-resolution 3T contrast-enhanced magnetic resonance imaging (MRI) and MR angiography (MRA) of the scalp and intracranial arteries. PARTICIPANTS: Patients presenting with suspected GCA between January 2015 and December 2018. Four additional, non-database cases of GCA with intracranial involvement are also described. RESULTS: Of 197 patients, 168 had a contrast-enhanced MRI of the head and 51 had imaging findings suggestive of vasculitis. Five patients showed probable or definitive involvement of both the anterior and posterior intracranial circulation with isolated posterior intracranial circulation involvement in one additional patient. One of these patients showed evidence of acute posterior circulation ischemia and presented with vertigo but no evidence of ischemic optic neuropathy or ophthalmic artery enhancement. Of the 51 patients, 14 had abnormal enhancement of the ophthalmic arteries, including 1 with arteritic ischemic anterior optic neuropathy and vertebral arteritis and 1 patient with involvement of the internal carotid and posterior cerebral arteries but no reported vision changes. CONCLUSION: Although uncommon, clinicians should be aware that GCA can directly involve the intracranial circulation with both the anterior and posterior circulation affected in most of our cases.