There is focal myelopathy of the medulla oblongata with cloudy medullary contrast enhancement and enlarged tortuous perimedullary veins.

The cause of this symptomatic high cervical myelopathy was a dural arteriovenous fistula (short 'dAVF'). In the Cognard/Merland/Djindjian classification of dAVFs this represents a textbook case of a type V fistula, which means it is an intracranial fistula with exclusively spinal perimedullary venous drainage.

In this case, the dAVF was supplied by the tentorial artery (Bernasconi/Cassinari) exclusively, which renders the angiographic images well arranged, which is not the case in many dAVF patients where several supplying arteries are usually present. In this exact case, the point of the arteriovenous fistula is identified close to the left petrous bone in TOF angiogram, where a round structure marks the beginning of the venous drainage. In the post contrast MRI and CT-A dilated tortuous perimedullary veins are seen, which is usually the best clue a dAVF is present. 

Endovascular treatment was performed. This patient was treated by transarterial embolization via the bernasconi artery. This artery is difficult to catheterize with a microcatheter, but a selective catheterization could be achieved using a balloon in the distal ICA as hypomochlion, and a wedge flow position could be established. Diluted histoacryl was used as an embolic agent. The embolization was successful because it reached the point of arteriovenous fistula and occluded the origin of the draining vein. 

The patient showed quick symptom relief within a few days of treatment.

MRI and CT imaging courtesy of Dr. Asmus Wulff (Christliches Krankenhaus Quakenbrück, Germany), angiogram and endovascular treatment imaging courtesy of Prof. R. Chapot and PD Dr. P. Mosimann (Alfried Krupp Krankenhaus Essen, Germany).