Abstract
The recurrence of an oculomotor nerve palsy due to invasion of the oculomotor nerve by coil loops extruded from a previously embolized internal carotid-posterior communicating artery aneurysm (IC-PC AN) is extremely rare.
A 69-year-old woman presented with a right oculomotor nerve palsy. Magnetic resonance angiography revealed a right IC-PC AN. Coil embolization was performed, and the oculomotor nerve palsy resolved. However, 4 and a half years later, the diplopia returned. Digital subtraction angiography revealed a slight recurrence of the aneurysm at the neck, with coil loops protruding to the outside of the coil mass. During microsurgery, the extrusion of previously embolized coils was observed. The extruded coil loops were embedded in the right oculomotor nerve. The aneurysm was clipped at the neck, the coils were cut at the aneurysm sac, and decompression of the oculomotor nerve was accomplished without removing the coils. The oculomotor nerve palsy did not improve after surgery.
It is still controversial whether microsurgical clipping or endovascular coil embolization is better for treating unruptured IC-PC AN causing oculomotor nerve palsy. If coil embolization is selected, there is a risk of oculomotor nerve palsy recurrence due to coil extrusion, and long-term follow-up is necessary.
