Is thrombosis of a developmental venous anomaly considered a stroke?

A fellow caregiver asked...

Is thrombosis of a developmental venous anomaly considered a stroke or is something else? Is this like an arterial stroke? There were changes on the MRI and CAT scan.

Expert Answer

James Castle, M.D. is a neurologist at NorthShore University HealthSystem (affiliated with The University of Chicago) and an expert on strokes.

This is, unfortunately, an extremely tricky question with no clear cut answer. Venous clots in the brain are very rare, and developmental venous anomalies causing symptoms are also very rare. It is unlike an arterial stroke.

This particular problem will likely require the collaboration of a Neurovascular Surgeon - different than a Stroke doctor. Developmental venous anomalies (DVA) are almost never the cause of a neurological attack. On rare occasions, they will bleed, and this often requires an operation to remove the DVA. Alternatively, if the DVA causes seizures that cannot be controlled by medications, they will be surgically removed. However, often times the DVA is crucial to the routine circulation of blood, as the person was born with the DVA, and therefore areas of their brain rely on it for blood to be recirculated to the venous system. For this reason, it is dangerous to remove a DVA unless there is a clear cut reason to do so.

If there truly is a clot in a DVA, I think therapy would be based on whether or not that clot is causing a symptomatic problem with blood flow in the brain. If it such a clot were to cause a back-up of venous drainage, and become symptomatic, I suppose consideration for treating with blood thinners to open up the clot would be reasonable. However, these decisions require a close examination of the patient and the images of the brain. Therefore, I recommend that you work very closely with a Neurovascular Surgeon, with the possible help of a Stroke Physician.

Good luck!