A Very Rapidly Growing, Spontaneous, Internal Carotid Artery Dissecting Aneurysm Triggering Simultaneous Complete Ophthalmoplegia and a Cerebral Infarct.

Background: Simultaneous ipsilateral complete ophthalmoplegia and multiple cerebral infarctions are very rare, especially secondary to a very rapidly growing, spontaneous dissecting aneurysm in the cavernous segment of the internal carotid artery (ICA). Case description: We describe a 26-year-old woman who presented with sudden-onset, right-sided, spontaneous ophthalmoplegia with left hemiparesis. Magnetic resonance imaging revealed a middle cerebral artery territory infarction. Digital subtraction angiography (DSA) revealed multiple arterial dissections involving both the vertebral artery and right ICA, with a dissecting aneurysm in the cavernous segment of the ICA. On day 3, the partial ophthalmoplegia worsened to complete ophthalmoplegia (third, fourth, and sixth cranial nerve palsies), despite conservative treatment. Follow-up DSA showed increased aneurysm size. The dissecting aneurysm was successfully managed by stent-assisted coil embolization. After endovascular treatment, the ophthalmoplegia, ptosis, and headache gradually resolved.

Conclusion: This is the first reported case of simultaneous cerebral infarction and complete ophthalmoplegia attributed to a rapidly growing dissecting aneurysm of the cavernous ICA; such aneurysms readily cause thromboembolism. Physicians who treat patients with dissecting aneurysms should carefully monitor aneurysm growth.