With the introduction of selective spinal arteriography in the 1960s and with the introduction and widespread use of MR imaging, the initial challenge of diagnosing spinal vascular malformations was overcome, and significant progress has been made in understanding their anatomy as well as the pathophysiology that underlies the myelopathy commonly associated with them. The anatomical features defined by selective arteriography and the observations permitted with the operating microscope ultimately led to distinctions between the major categories of the vascular lesions affecting the spinal cord; these distinctions were based on the lesions' anatomy, epidemiology, and the mechanism of spinal cord injury ¹⁾.