Objective and importance: We present the case of a patient with bilateral dissecting aneurysms of the vertebral arteries resulting in subarachnoid hemorrhage.
Clinical presentation: A 44-year-old man suffered a sudden onset of severe occipital headache and nausea and then dysphasia caused by subarachnoid hemorrhage. A computed tomographic scan demonstrated right side dominant subarachnoid hemorrhage mainly in the posterior fossa. Angiography revealed bilateral, vertebral dissecting aneurysms. The right aneurysm was larger and had a bleb-like protrusion, which strongly suggested a causative lesion of the subarachnoid hemorrhage. Six months later, the patient was referred to our hospital for further evaluation and treatment.
Intervention: The ruptured right aneurysm was trapped surgically through a lateral suboccipital approach. The patient's postoperative course was unremarkable, and he was discharged on the 14th day after surgery. However, postoperative angiography demonstrated slight enlargement of the left nonruptured aneurysm. Four months after surgery, the patient developed brain stem ischemic symptoms. The angiography conducted at that time showed further enlargement of the left aneurysm. Five months after surgery, fatal rupture of the left aneurysm occurred.
Conclusion: These results indicate that sacrifice of the unilateral vertebral artery may result in an enlargement of the contralateral nonruptured aneurysm and may thus be dangerous in the case of a patient with bilateral dissecting aneurysms.