Objective:

Background:

The azygos anterior cerebral artery (ACA) is a vascular anomaly characterized by a singular A2 segment, found in less than 2.2% of the general population. ACA strokes account for less than 1.3% of all ischemic strokes and infarcts in patients with an azygos ACA are rare making diagnosis and management extremely challenging.

Design/Methods:

N/A

Results:

A 34-year-old male with morbid obesity, hypertension, alcohol and marijuana use disorders who presented with hyperacute onset bilateral lower extremity weakness (right more than left) along with difficulty standing and walking. Exam revealed mild bilateral lower extremity paresis, hyperreflexia with upgoing toes and difficulty ambulating. Computed tomography (CT) scan of the head demonstrated a hyperdense sign within the interhemispheric fissure over the rostrum of the corpus callosum and CT Angiography (CTA) confirmed proximal occlusion of an azygos ACA. CT Perfusion (CTP) demonstrated large penumbra in bilateral ACA territories and small infarct core. Per our institutional protocol, the patient received late-presenter thrombolysis 5 hours after Last Known Well (LKW). On discussion, thrombectomy was deferred since risks were deemed to outweigh benefits. Subsequent brain magnetic resonance imaging (MRI) showed minimal infarct burden in both ACA territories without intracranial hemorrhage. Upon discharge, the patient exhibited minimal difficulty walking but this was resolved by follow-up visit two months later. Despite exhaustive workup, stroke etiology remains cryptogenic.

Conclusions:

Hyperacute atraumatic paraparesis should raise suspicion for azygos ACA AIS, prompting emergent neuro-imaging of not only the spinal cord but also the brain parenchyma and its vasculature.