Reversible carotid artery narrowing in morning glory disc anomaly.

A 14-year-old boy with morning glory disc anomaly (MGDA) and normal visual and neurologic function displayed marked carotid artery narrowing on magnetic resonance angiography (MRA). This narrowing disappeared on a follow-up MRA six months later. Optic coherence tomography and scanning laser polarimetry disclosed a normal retinal nerve fiber layer in the eye with MGDA. MGDA has been reported in association with irreversible carotid artery stenosis leading to moya moya disease. This case suggests that mild cases of MGDA may be associated with reversible carotid artery narrowing owing to vasospasm.