Upper cranial nerve palsy resulting from spontaneous carotid dissection

Upper cranial nerve palsy has a variety of causes such as cerebral and nerve ischemia, diabetes, infectious and non-infectious meningitis, subarachnoid hemorrhage and intracranial aneurysm. CASE 1 : A 45-year-old man suffered from holocephalic headaches and a right-sided neck pain for two weeks. He presented to our emergency department because of a sudden ptosis of the right eye. On admission neurological examination revealed a right sided Horner's syndrome and hypesthesia of the right side of the face. Magnetic resonance angiography identified a circumscribed dissection of the right extracranial internal carotid artery originating from the carotid bifurcation. Conventional angiography 2 weeks later showed a nearly recanalized artery. CASE 2 : A 55-year-old previously healthy man without cardiovascular risk factors developed right sided neck pain when loading a seeder with several sacks of crop. A few hours later he noticed a left-sided weakness. On admission a severe left sided hemiparesis and a mild neglect were present. Duplex sonography revealed a right-sided distal internal carotid artery (ICA) occlusion. The next morning the patient complained of double vision; he had a right-sided pupil-sparing oculomotor palsy. The diagnosis of ICA dissection was confirmed by conventional angiography, at that time showing a partially recanalized ICA without involvement of the cavernous region by the dissection.

ICA dissection must be included in the differential diagnosis of upper cranial nerve palsy and should be assessed by duplex ultrasound and magnetic resonance imaging. A possible explanation is nerve ischemia due to a transient or permanent interruption of the blood supply by compression of the vasa nervorum originating from the intracranial carotid artery.