Endovascular Treatment for Fungal Internal Carotid Artery Aneurysm

Fungal cerebral aneurysms, particularly those resulting from direct invasion by fungal sinusitis, are rare and often fatal when involving the cavernous segment of the internal carotid artery (ICA). We present a case of a ruptured fungal ICA aneurysm caused by <i>Aspergillus</i> sinusitis, successfully treated with parent artery occlusion (PAO). In this case, an 80-year-old woman presented with right ptosis, facial pain, and cranial nerve III, IV, and VI palsies. Magnetic resonance imaging (MRI) and angiography revealed a spindle-shaped aneurysm in the cavernous segment of the right ICA with sphenoid sinus invasion. A balloon occlusion test demonstrated tolerance to ICA occlusion. Polymerase chain reaction analysis of sinus pus confirmed <i>Aspergillus fumigatus</i>. Despite antifungal therapy and sinus irrigation, the aneurysm enlarged. While flow diversion was being planned, the aneurysm ruptured, causing massive epistaxis and shock. Emergent PAO using a double catheter technique was performed, preserving collateral flow via the anterior and posterior communicating arteries. Postoperatively, the patient had no new neurological deficits, with only residual oculomotor palsy. This case highlights the importance of early balloon occlusion testing in the management of fungal ICA aneurysms because of their high risk of rupture. Tight coil packing using a double catheter technique can minimize ischemic complications while preserving vital collateral circulation.