Teaching neuroImages: Magnetic resonance susceptibility effect for acute isolated cortical vein thrombosis.

A 38-year-old woman using hormonal contraception presented with right-sided abdominal and arm clonic seizures, right hemiparesis, hypesthesia, and nausea. She denied headache. D-dimers were 350 ng/mL (laboratory reference #500 ng/mL). CT showed a small left parietal hemorrhagic infarct with adjacent hyperdense cortical vein (figure 1). MRI 15 hours after onset showed magnetic susceptibility effect on susceptibility-weighted imaging (SWI, figure 2). Isolated cortical vein thrombosis is present in 5% of patients with cerebral venous thrombosis (CVT). Negative D-dimer and absence of headache does not exclude CVT and SWI is useful for confirmation of the diagnosis. Figure 1 Baseline noncontrast CT scan