Slowly Recovering Isolated Bilateral Abducens Nerve Palsy after Embolization of Ruptured Anterior Communicating Artery Aneurysm
A 32-year-old man visited our institution for the evaluation of horizontal diplopia, dizziness and headache after the onset of a 5-minute generalized tonic-clonic seizure. On admission, the patient was alert and did not have any possible vascular risk factors such as hypertension, diabetes mellitus, hyperlipidemia, advanced age and cigarette smoking. The attending neurosurgeon and opthalomologist did not find any abnormality except slight nuchal rigidity and bilateral abducens nerve palsy (). Initial cranial computed tomography (CT) () revealed no definite high density lesion in the brain including parenchyma, ventricle and cisternal space, but CT angiography () showed an aneurysm of the ACoA. Magnetic resonance imaging (MRI) () demonstrated focal intraventricular hemorrhage of the posterior horn of the lateral ventricle without abnormalities of the brain stem including infarction or space-occupying lesion. Catheter angiography was followed and a bilobulated saccular aneurysm (6.3×4.0 mm, dome×neck) without compression of brainstem was observed (). Endovascular coil embolization was conducted to obliterate the aneurysmal sac without delay. Continuous lumbar drainage was performed for 6 days. A photograph taken 12 days later illustrated the improvement in both abducens nerve palsy (). The signs of diplopia were resolved completely 9 weeks later (). There were no clinical and radiologic signs of vasospasm during hospitalization.