Bilateral Anomalous Ophthalmic Artery Course With an Internal Carotid Artery Configuration Mimicking Moyamoya Angiopathy

A neurologically normal woman in her 40s presented with headache.MRI demonstrated a chronic ischemic lesion, and MRA showed poor visualization of both terminal internal carotid arteries (ICAs) (Figure 1, A and B).DSA revealed both ICAs transitioning smoothly into the ophthalmic arteries (OAs) without visualization of the carotid siphon (Figure 1, C and D).Moyamoya-like collaterals and transdural collaterals were observed (Figure 1, C-F).CTA showed the left OA penetrating the optic strut (Figure 2, A and B) and the right OA coursing along the caudal optic canal (Figure 2, C and D).The vascular course relative to bony structures suggested a congenital vascular anomaly rather than moyamoya angiopathy.Subsequent genetic testing identified a heterozygous RNF213 variant of uncertain significance.Previous reports described similar unilateral configurations in moyamoya disease and extradural OA variants, including transoptic strut and supraoptic strut types.1,2 Moyamoya-like collaterals Figure 1 MRI, MRA, and Digital Subtraction Angiography Findings MRI showed a small chronic ischemic lesion (white arrow) (A).MRA demonstrated poor visualization of the terminal portions of both ICAs (yellow arrow) (B).The left ICA coursed smoothly toward the OA, with no visualization distal to its origin (C).The right ICA showed a similar course (D).The left ACA and left PCoA were visualized, and the terminal portion of the left ICA was identifiable, whereas the terminal portion of the right ICA was not visualized.The left MCA originated from the terminal ICA, whereas the right MCA was supplied through the PCoA (E).The right parietal lobe was supplied through transdural collaterals from the right MMA (F).Abnormal vascular networks suggestive of moyamoya-like collaterals were observed (C-E).ACA = anterior cerebral artery; AP = anteroposterior; ECA = external carotid artery; ICA = internal carotid artery; MCA = middle cerebral artery; MRA = magnetic resonance angiography; MMA = middle meningeal artery; OA = ophthalmic artery; PCoA = posterior communicating artery; VA = vertebral artery.