The Lurking Catastrophic Complication of an Equally Catastrophic Disease: The Lesson Learned.

BACKGROUND: Medullary-bridging vein dural arteriovenous fistula (DAVF) is an uncommon type of DAVF with an aggressive clinical course due to direct fistulous shunting into medullary and brainstem veins. Important considerations need to be given to retrograde embolic migration or perforator involvement while treating these fistulas endovascularly with a liquid embolic agent. We report a lateral spinal artery feeding the DAVF, the recognition of which is important to avoid potential catastrophic complications during definitive therapy, and which has not been described before.

OBJECTIVE: To discuss the anatomy of the lateral spinal artery (LSA) and its communications with pial arteries such as the posterior inferior cerebellar artery (PICA) that may have important implications in the management of neurovascular diseases in and around the foramen magnum.

METHODS: A retrospective analysis of cerebral angiograms and 3-dimensional rotational angiograms of a patient with medullary-bridging vein DAVF treated by transarterial embolization under balloon protection was performed after the patient developed lateral medullary syndrome in the postoperative period.

RESULTS: Detailed analysis revealed a dural branch from the LSA feeding the DAVF which anastomosed with rudimentary PICA.

CONCLUSION: LSA has important anastomoses with perforating arteries of the medulla and cervical cord and, hence, it is important to recognize and identify LSA prospectively in the vascular pathologies of the foramen magnum to avoid fatal neurological complications during endovascular therapy. This is especially important while treating neurovascular pathologies using liquid embolic agents such as Onyx or SQUID, because they can percolate retrogradely through the anastomoses into PICA or other vertebrobasilar perforators.

ABBREVIATIONS: DAVF, vein dural arteriovenous fistulaLSA, lateral spinal arteryPICA, posterior inferior cerebellar artery.