Abstract
BACKGROUND: The recurrent artery of Heubner (RAH) is a branch of the anterior cerebral artery that supplies blood flow to key deep cerebral structures. Aneurysms in the main trunk of the RAH are exceedingly rare, and previous reports have only confirmed cases after rupture. Here, the authors report on the rare course of an RAH aneurysm found in an unruptured state. OBSERVATIONS: This report presents a unique case of an unruptured RAH aneurysm in a 30-year-old woman who presented with persistent headache. Angiography revealed a 4.6-mm aneurysm originating from the right RAH. Endovascular parent artery occlusion was initially planned because of the patient's age and risk of rupture. However, repeat angiography 4 months later revealed spontaneous thrombosis of the aneurysm to 1.4 mm, leading to a shift toward conservative management. After that, MRI revealed thrombosis that resulted in asymptomatic cerebral infarctions within the RAH perfusion territory. LESSONS: This case highlights the potential for spontaneous thrombosis in RAH aneurysms. The awareness of spontaneous thrombosis as a possible outcome is critical for optimizing treatment approaches for this rare condition. https://thejns.org/doi/10.3171/CASE25295.