IMAGING OF SPINAL ARTERIO VENOUS FISTULAE–IMPLICATIONS FOR TREATMENT

Abstract

Background: When treatment of a spinal arterio venous fistula (SAVF) is anticipated, precise location of the level and side of the feeding artery are necessary. Digital subtraction angiography (DSA) is the reference standard for imaging SAVFs. Non-invasive vascular imaging by multidetector computed tomographic angiography (MDCTA) and magnetic resonance angiography (MRA) are newer imaging modalities, which are able to demonstrate these lesions.

Objectives: We performed a retrospective analysis of patients with SAVF in our unit to examine the accuracy of MDCTA and MRA compared with DSA and intraoperative findings to illustrate how non-invasive angiography affects treatment.

Results: Between 2001 and 2007, we identified 22 consecutive patients with SAVF. 20 patients had CTA, identifying the site of SAVF in 19. In all of the 11 patients who had MDCTA, the site was correct and confirmed at surgery.

16 patients had MRA, confirming the SAVF in all cases and correct site in 12.

DSA failed to demonstrate the abnormality in one patient.

Treatment: 5 patients have had no treatment. 3 patients were treated by embolisation, with one patient developing a persistent neurological deficit. 14 patients had primary surgical repair with confirmation of the angiographic lesion. In those cases where pre-operative MDCTA was performed, volume rendered spinal reconstructions aided the operative localisation.

Conclusion: Non-invasive angiography for the diagnosis of SAVF is safe and accurate. MDCTA aids operative localisation and DSA should be reserved for patients with inconclusive non-invasive angiography or when identification of the artery of Adamkiewicz is required prior to embolisation.