Atypical vertebral artery in a patient with an intra-and extraspinal cervical neurenteric cyst.

A 15 year old girl experienced Horner's syndrome on the right side, paraesthesia of the right arm and meningitis. CT and MRI showed a cystic lesion on the right side of the cervical spine at C3/C4 which descended with an extraspinal portion down to C6. Histology revealed a complex neurenteric cyst. The ipsilateral vertebral artery showed an atypical course. This abnormal artery besides a partial fusion of the vertebrae C2/C3/C4 suggest a complex malformation at the site of the cyst. Disturbed developmental relationships in this case indicate that pathological blood vessels may represent a risk factor in the surgical treatment of neurenteric cysts.