Spinal Arteriovenous Shunts: Angioarchitecture and Historical Changes in Classification

Abstract

The purposes of this study were to review historical changes in the classification of spinal arteriovenous (AV) shunts and to propose a practical classification system. The associated literature regarding the classification of spinal AV shunts was reviewed in the angiography era between 1967 and 2015. The classification systems of spinal AV shunts and a proposed classification system were presented with neuroradiological imaging and medical illustrations. There have been seven major classification systems based on the evolution of diagnostic methods as well as treatments for spinal AV shunts: the first description of spinal AV shunts diagnosed and classified using spinal angiography in 1971; the second classification based on a case report of intradural direct perimedullary arteriovenous fistulas (AVFs) treated by microsurgery in 1987; the third classification based on a case series of intradural perimedullary AVFs treated by endovascular interventions in 1993; the fourth and fifth classification systems based on a case series of spinal AVFs and arteriovenous malformations (AVMs) treated by microsurgery or endovascular interventions in 2002; the sixth classification based on a case series of cranio-spinal dural AV shunts in 2009; and the seventh classification based on a case series of extradural AVFs treated by microsurgery and endovascular interventions in 2011. Based on historical reports, the author proposed a classification system according to the sites (dural, intradural, and extradural) and types (AVF and AVM) of AV shunts. By learning the historical background, we may obtain a clearer understanding of the complex and confusing classification system of spinal AV shunts.

A rare case of a cervical dural arteriovenous fistula presenting in a younger patient with vertex subarachnoid hemorrhage: Case report and literature review

“…The first clinical observation of a spinal vascular malformation was published in Germany in 1890 by Berenbruch [1] . Whereas the first description by clinical angiography was in 1967 by Di Chiro from National Institute of Health, USA [5] . To date there have been seven classification systems for these entities [5] , with the 2 leading systems in use being the American/British/French system and the Spetzler classification [2] .…”

“…Whereas the first description by clinical angiography was in 1967 by Di Chiro from National Institute of Health, USA [5] . To date there have been seven classification systems for these entities [5] , with the 2 leading systems in use being the American/British/French system and the Spetzler classification [2] . As per the American/British/French system the Type I lesions, or the “single coiled vessel” type, are dAVFs and consist of a radicular artery draining into an engorged spinal vein on the dorsal aspect of the dural sheath of a nerve root [2] .…”

“…For some lesions, surgery remains the treatment of choice, particularly when the arterial supply is in close association with the ASA, PSA, or artery of Adamkiewicz; in those cases, the risk of spinal cord ischemia and worsening of neurological function with curative embolization may be prohibitive [1] . The liquid embolic agents include n-butyl cyanoacrylate and Onyx with these agents showing low recurrence rates (0%-25%) [ 4 , 5 ]. Our case was unique because of the younger age, no preceding symptoms and SAH that occurred over the convexity rather than the cisterns or posterior fossa, which has been described [3] .…”

Spinal Arteriovenous Fistula, A Manifestation of Hereditary Hemorrhagic Telangiectasia: A Case Report

“…Perimedullary AVFs commonly develop at the ventral portion of the spinal cord, while dural AVFs commonly develop at the dorsolateral portion of the dura mater. 11 Dorsal AVFs are typically low flow, and lead to congestive myelopathy that affects the caudal end of the cord regardless of the level of fistula. 12 The majority of AVFs are idiopathic and detected only when symptoms arise, with acute or subacute presentation, presenting as severe neurological deficits, progressive myelopathy, or subarachnoid hemorrhage.…”

Treatment of Intradural Spinal Arteriovenous Fistula: Technical Case Report

“…There are many types of spinal vascular malformations. 2 However, the classification made by Spetzler et al, which was based on a case series, 5 is the most used. It has been divided into two main groups: AVFs and arteriovenous malformations.…”