Background: Spontaneous recanalization in a completely thrombosed giant aneurysm is a very rare condition.
Case description: An 18-year-old woman presented with a serpentine variety giant aneurysm of the posterior cerebral artery, in which spontaneous recanalization of a completely thrombosed lumen was demonstrated on magnetic resonance imaging and angiography. The patient was treated by trapping of the parent artery and aneurysmectomy.
Conclusion: This case will provide insight into the potential for spontaneous recanalization in completely thrombosed giant aneurysms.