Spinal phlebography is an "indirect" radiologic technique for investigating verte bromedullary pathology. It is a harmless and almost painless technique that does not require the introduction of contrast medium into the subarachnoid spaces. Its interpretation is based on the modifications of the epidural veins which do not themselves have any proven pathology. The longitudinal epidural veins are situated in the anterolateral angles of the spinal canal between the nerve root and the intervertebral disc. They conse quently represent a major anatomic landmark in the investigation of disc pathol...