[Medulla and upper cervical cord compression by bilateral vertebral artery presented with myelopathy and drop attack: case report].

A 51-year-old man had suffered from attacks of quadri-paresis and unconsciousness for previous three years prior to presentation. Prior to admission, he had been received anticonvulsants, but his symptoms showed no improvement. Neurological examination revealed hyper-reflexia of his left lower extremity and moderate decrease of sense of pain, temperature, and tactile sensation in his left extremities and trunk, while vibratory sensation was normal. Magnetic resonance(MR) imaging revealed a flow-void area in the craniocervical junction and marked narrowing of the medulla oblongata and upper cervical cord by compression of the vertebral arteries(VA). CT myelography also showed the compression and narrowing of the spinal cord. Vertebral angiography demonstrated symmetrical running course of the arteries, which curved medially at the level of craniocervical junction. Suboccipital craniectomy and C1 and upper half of C2 laminectomies were performed. After dural opening, the ventrolateral aspects of the lower medulla oblongata and the upper cervical cord were found to be compressed by the VA. The arteries were retracted dorsolaterally by GORE-TEX tapes so as to decompress the medulla oblongata and cervical cord, and the tapes were anchored to the residual part of C1 posterior arch. Postoperative MR imaging and CT myelography showed complete decompression, and the patient was relieved of his previous neurological symptoms.