Bilateral dissecting aneurysms of the internal carotid arteries misdiagnosed as skull base tumors: A case report.

A 45-year-old female presented with a five-year history of intermittent headaches and a two-month history of left hypoglossal nerve palsy. Computed tomography and magnetic resonance imaging of the head revealed space-occupying lesions in the base of the skull with accompanying bone erosion, which were suggestive of skull base chordomas. However, an endoscopic endonasal transsphenoidal biopsy was also performed and pathological analysis of the lesion suggested a thrombosis. Cranial magnetic resonance angiography revealed old dissecting aneurysms of the bilateral internal carotid arteries (ICAs), which led to a definitive diagnosis. The patient was successfully treated with anticoagulants and antiplatelet agents. The present case study suggests that, for patients with space-occupying lesions of the skull base and symptoms of cranial nerve palsy, the possibility of an ICA dissection should be prioritized during the differential diagnosis.