[Developmental cerebral thrombosed venous anomaly: findings in magnetic resonance imaging].

Introduction: Developmental venous anomalies are the most common cerebral vascular malformations. They are usually incidental and benign, although about 40% are associated with cavernous malformations, and so it is essential to look for other associated vascular or neurocutaneous anomalies.

Case Report: We report the case of a 34-year-old pregnant woman who presented with seizures and dysarthria, and was submitted to an urgent cranial MRI scan. She showed the classic 'Medusa head' sign and was diagnosed with developmental venous anomaly with partial peripheral thrombosis and slow proximal flow.

Conclusions: Thrombosis rarely occurs as a complication of developmental venous anomalies and case reports in the literature suggest that they should be managed conservatively, leaving surgery for other associated complications. As radiologists, we must be aware of the main imaging features so as to be able to make an accurate diagnosis.