Cerebral amyloid angiopathy-related transient focal neurological episodes: A transient ischemic attack mimic with an increased risk of intracranial hemorrhage

Background: Transient focal neurological episodes (TFNEs) are a recently recognized clinical presentation of cerebral amyloid angiopathy (CAA). Our aim was to describe the clinical and radiological features of a series of patients with AS. Methods: We included 11 patients presenting with recurrent transient focal neurological symptoms and radiological features related to CAA. Results: Mean age was 76,6 and 5 patients were women. All patients reported transient, stereotyped, and recurrent episodes (6 patients had > 10 episodes). Gradual spread of the symptoms was recorded in 9 patients. Initially, 3 patients were misdiagnosed as having recurrent transient ischemic attack (TIA), 6 as having seizures, and 2 as having both. Two patients were prescribed antiplatelet therapy. A cerebral MRI with T2* gradient-recalled echo sequence revealed cortical superficial siderosis (cSS) in 5 patients, cortical microbleeds in 1 patient, and both features in 5 cases. After a median follow-up of 36 months, intracranial hemorrhage (ICH) was recorded in 4 patients. All 4 had cSS in the previous cerebral MRI, and 1 was on antiplatelet therapy. Conclusion: CAA-related TFNEs are an underdiagnosed entity, often mimicking TIA, seizures, or migraine aura. This misdiagnosis can lead to the prescription of antiplatelet or anticoagulant therapy, which increases the risk of ICH. Our results suggest that cSS might be a radiological marker that is closely related to an increased risk of bleeding. A T2* gradient-recalled echo MRI should be performed in elderly patients with transient focal neurological symptoms suggestive of CAA.