Intraparenchymal hemorrhage and cerebral venous thrombosis in an adult with congenital porencephalic cyst presenting for generalized tonic-clonic seizures.

Prothrombotic conditions are known risk factors for porencephalic cyst formation and cerebral vein thrombosis. Intracerebral hemorrhage is a potential complication of a cerebral vein thrombosis. Porencephaly is a risk factor for intracerebral hemorrhage and cerebral vein thrombosis formation. We present the case of an adult patient with a past medical history of epilepsy and congenital porencephalic cyst with de novo mutation of the COL4A1 gene who presented for episodes of generalized tonic-clonic seizure after a substantial symptom-free period. A brain CT scan showed an intracerebral hemorrhage with porencephalic cyst and superior sagittal sinus thrombosis despite negative thrombophilia work-up. A CT perfusion study, CT angiography, and brain MRI confirmed the diagnosis. The cause-and-effect relationship between porencephalic cysts, cerebral venous thrombosis, and intracerebral hemorrhage is still not clear in the literature.