Intermittent vertebral artery compression caused by C1-root schwannoma: case report.

Extradural schwannomas of the C1-root are extremely rare. As the tumor grows in size, it may compress surrounding neurovascular structures and cause symptoms. In the present case report, the left vertebral artery (VA) was severely compressed by the tumor, eliciting severe vertigo on turning the head to the right side and with neck extension. We report a 52-year-old man who presented with a history of intermittent episodes of severe vertigo on head movement that was caused by a C1-root schwannoma. The lesion was exposed through an extreme lateral transcondylar approach. At exposure the lesion was yellowish in color and was extradural in location lying between the markedly eroded C1-posterior arch and the compressed vertebral artery (V3) on the left side. The medial portion of the tumor was attached to the C1-nerve root. The tumor was excised enbloc with decompression of the VA. The patient's symptoms completely resolved immediately following surgery, with no recurrence of the symptoms at one year follow up. The vertebral artery may frequently be compressed by osteophytes in cervical spondylosis or due to other causes in the cervical spinal canal, but compression of the artery by C1 extradural schwannoma with vascular insufficiency is rare. Removel of the tumor and the resultant decompression of the artery can be facilitated by the extreme lateral approach as demonstrated by this case.