Plastic in the Brain: Delayed Recognition of Progressive Unilateral Hemispheric Lesions.

BACKGROUND: Flow diverters are increasingly used to treat complex ruptured intracranial aneurysms. Most complications are ischemic and seen early after placement.

METHODS: We present a patient with 3 year duration of neurologic symptoms and seizures as a result of lesions associated with a inflammatory response to embolized polymer coating.

RESULTS: Over a period of 3 years MRI abnormalities were noted with substantial gadolinium enhancement of the stent but with resolution after corticosteroids.

CONCLUSION: Polymer embolization associated with a flow diverter may cause fluctuating unilateral hemisheric lesions and become symptomatic. Inflammatory response to a foreign body (polymer strands) can be succesfully treated with corticosteroids.