Unique Angioarchitecture of Sacral Dural Arteriovenous Fistula

Background: Spinal dural arteriovenous fistulas (DAVFs) in the sacral region are extremely rare. The location and complex angioarchitecture of these lesions make both identification and treatment challenging, even in experienced hands. We report on a sacral DAVF with a unique angioarchitecture and discuss its specific anatomy.

Case description: A 76-year-old male presented with progressive distal paraparesis and spinal ataxia. Three lumbar decompression surgeries were performed between 2016 and 2018 elsewhere on the basis of suspected degenerative lumbar syndrome. On admission to our center, the patient was wheelchair dependent due to extensive spinal ataxia associated with bilateral foot paresis and hypoesthesia. Spinal contrast-enhanced time-resolved magnetic resonance angiography and digital subtraction angiography were performed after admission to our center. Contrast-enhanced magnetic resonance angiography examinations suggested a sacral DAVF. Subsequent digital subtraction angiography demonstrated a spinal DAVF on the left side at the S2 vertebral level supplied via an arterial epidural branch from the right L4 segmental artery. The fistula was treated via surgical interruption of the proximal part of the radicular drainage vein.

Conclusions: Sacral DAVFs present serious diagnostic difficulties and require a profound understanding of possible fistula-supplying arteries of the sacral region. Microsurgical interruption of the often ventrally located drainage vein presents an efficient treatment modality and could provide an immediate confirmation of fistula occlusion using indocyanine green videoangiography.