Mixed Vascular Malformation

developmental venous anomaly

This T1-weighted contrast-enhanced MR image shows a developmental venous anomaly, otherwise known as venous angioma. DVA is a congenital malformation of veins which drain normal brain. It is characterised by a Medusa head of veins draining into a single larger collecting vein, which in turn drains into either a dural sinus or into a deep ependymal vein. The appearance has also been likened to a palm tree. Usually these lesions are solitary, except in blue rubber bleb naevus syndrome, but are common, seen in 2.5 – 10% of autopsy specimens.

The two most common locations are:

* frontal lobe draining towards the frontal horn of the lateral ventricle (as in this case)
* cerebellar hemisphere draining towards the fourth ventricle (see Case 2)

When isolated, a DVA has a very low complication rate mainly from spontaneous thrombosis of the collecting vein leading to venous infarction and haemorrhage. DVA are however commonly associated (15 – 20%) with other vascular malformations, most commonly a cavernous malformation, as in this case. In this circumstance they should be referred to as mixed vascular malformations. Their risk of complication is then elevated to that of the associated lesion.

For more sequences of this case please visit Radiopaedia.org here.

Reference: Osborn, A. Diagnostic Imaging – BRAIN. Amirsys

Credit: Dr Frank Gaillard