Spinal perimedullary fistula

Thus, acute, subacute, or chronic impairment of spinal blood supply can result from a deficient arterial supply and from venous circulatory problems (Mull and Thron 2004). Spinal vascular malformations like spinal dural arteriovenous (AV) fistulas and AV malformations (AVM) of the perimedullary fistula type are the typical disorders associated with venous congestion of the spinal cord. On the other hand, AVM of the glomerular type are seldom combined with a venous outflow disorder. 

Spinal AVMs can be mainly divided into AVM of the perimedullary fistula type and glomerular type. Typically, congestive myelopathy is obvious in AVM of the perimedullary type (Heros et al. 1986 Rosenblum et al. 1987 Thron et al. 2001). 

AVMs of the perimedullary fistula type are direct AV shunts that are located on the ventral or dorsal surface of the spinal cord or the conus medullaris, usually in the thoracolumbar area, occasionally thoracic, and rarely cervical. Their location thus is intradural, intra- or extramedullary. They are always supplied by spinal cord vessels, either by the anterior spinal artery (ventrally) or by a posterolateral artery (dorsally), depending on their location. They drain into spinal cord veins (Fig. 17.12). Drainage may even ascend up to the foramen magnum or into the posterior fossa. 

Perimedullary fistulas type 1 may present with multisegmental hyperintensive cord lesions on T2-weighted images due to congestive myelopathy similar to spinal cord affection in spinal dural AVF. 

Therapeutically, cellulose acetate has been used to treat cerebral aneurysms, and also for spinal perimedullary arteriovenous fistulas. 

Sugiu K, Meguro T, Nakashiama H, Ohmoto T. Successful embolization of a spinal perimedullary arteriovenous fistula with cellulose acetate polymer solution technical case report. Neurosurgery 2001 49(5) 1257-1260. 

Chen CJ, Chen CM, Lin TK (1998) Enhanced cervical MRI in identifying intracranial dural arteriovenous fistulae with spinal perimedullary venous drainage. Neuroradiology... 

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