Concomitant conus medullaris arteriovenous shunts and sacral dural arteriovenous fistulas: pathophysiological links related to the venous drainage of the lesions in a series of five cases.

BACKGROUND: Spinal cord arteriovenous shunts (scAVSs) are a group of lesions located in the spinal cord itself or in the surrounding structures. The most common scAVSs are spinal dural arteriovenous fistulas (sDAVFs), which are acquired lesions. The pathogenesis of sDAVFs involves thrombosis and venous hypertension as trigger factors. Intradural scAVSs such as spinal cord arteriovenous nidus type malformations (AVMs) and pial arteriovenous fistulas are less common than sDAVFs and are considered to have a so-called 'congenital' origin. The association between different concomitant scAVSs is very rare and the association of sDAVFs with intradural scAVSs has been described in only a few case reports. METHODS: We describe a case series of five patients presenting with a conus medullaris AVS associated with a lower lumbar or sacral DAVF. RESULTS: Three of our patients were <30 years old at presentation. In four of these five cases the intradural scAVS drained caudally, engorging the epidural plexus in the same location as the sDAVF. In only one case, who presented with thrombosis of the drainage of the main compartment of a conus medullaris pial AVF, was the location of the DAVF opposite to the location of the residual drainage. CONCLUSION: We discuss the pathophysiological link between scAVS and sDAVF on the basis of the rarity of the DAVF, the uncommon association between scAVS and sDAVF, the presence of sDAVF in young patients, and the venous hypertension created by the venous drainage towards the sacral area responsible for angiogenesis creating the dural shunt.

Therapeutic management of intracranial dural arteriovenous shunts with leptomeningeal venous drainage: report of 53 consecutive patients with emphasis on transarterial embolization with acrylic glue.

OBJECT: There is a strong correlation between the venous drainage pattern of intracranial dural arteriovenous shunts (ICDAVSs) and the affected patients' clinical presentation. The ICDAVSs that have cortical venous reflux (CVR) (retrograde leptomeningeal drainage: Borden Type 2 and 3 lesions) are very aggressive and have a poor natural history. Although the necessity of treatment remains debatable in ICDAVSs that drain exclusively into a sinus (Borden Type 1), lesions with CVR must be treated because of the negative effects of the retrograde venous drainage. Surgery, radiosurgery, and embolization have been proposed for management of these lesions, but endovascular therapy is considered the most appropriate therapeutic strategy in ICDAVSs. New embolic materials, such as Onyx, have been recently developed and are considered to represent a kind of "gold standard" for embolization of these lesions. The purpose of this study is to emphasize the importance of transarterial embolization using acrylic glue in the therapeutic management of ICDAVSs with CVR, and to compare the results the authors obtained using this treatment with those reported in the literature for Onyx treatment of the same type of dural shunts. METHODS: The clinical and radiological records of 53 consecutive patients suffering from ICDAVSs with CVR (Borden Types 2 or 3) were reviewed. All cases were managed with the same angiographic and therapeutic protocol. Localization of the lesions, their clinical symptoms, their angioarchitecture, their therapeutic management, and the results were analyzed. RESULTS: Fourteen ICDAVSs were located at the superior sagittal sinus and/or convexity veins, 13 at the transverse and sigmoid sinuses, 10 at the tentorium, 5 in the anterior cranial fossa, 4 at the foramen magnum, 3 at the torcula, 2 at the straight sinus, and 1 at the vein of Galen. One patient presented with an infantile form of ICDAVS with multiple shunts. Hemorrhage had occurred in 36% of cases. Forty-three patients underwent transarterial embolization (42 with acrylic glue). Complete closure of the fistula was obtained in 34 patients. Suppression of the CVR with partial occlusion of the main shunt was achieved in all other cases. No mortality or permanent morbidity was observed in this series. CONCLUSIONS: Intracranial dural arteriovenous shunts can be safely managed by transarterial embolization, which can be considered in most instances as an effective first-intention treatment. Acrylic glue still allows a cheap, fast, and effective treatment with high rates of cures that compare favorably to those obtained with new embolic materials.