**2.5 Cerebral venous thrombosis**

In patients with cerebral venous thrombosis (CVT), early seizures were seen in 6.9–76% [71], status epilepticus in 6% [40], late seizures in 11% [43], and post-CVT epilepsy in 4–16% [71]. Risk factors for early seizures following cerebral sinus thrombosis include brain parenchymal lesions, focal neurological deficits, supratentorial parenchymal lesions, intracerebral hemorrhage, focal edema/ischemic infarction, superior sagittal sinus thrombosis, cortical venous thrombosis, and pregnancy/puerperium [72–77]. Known risk factors for late seizures after CVT are early seizures, baseline intracerebral hemorrhage, decompressive hemicraniectomy, sigmoid sinus thrombosis, loss of consciousness at presentation, and genetic thrombophilia [43, 75, 78].

In the absence of previous early seizure following cerebral venous thrombosis, there is no evidence to prescribe prophylactic antiepileptic drugs during acute phase [40]. European and American guidelines recommend antiepileptic drug treatment on CVT for patients with early seizures and supratentorial lesions in order to prevent further seizures [79, 80].

Due to the high recurrence risk of late seizures, epilepsy diagnosis and commencement of antiepileptic drugs following a first late seizure after CVT is reasonable [43].
