The term idiopathic subarachnoid hemorrhage implies a primary subarachnoid hemorrhage without a known cause. Secondary subarachnoid hemorrhage results from a spill of blood into the arachnoid space from a brain parenchymal hemorrhage, an intraventricular hemorrhage, or a hemorrhagic infarct. The term secondary subarachnoid hemorrhage is also used for hemorrhages in the subarachnoid space if the cause is known. Seizures are the most common manifestations. They usually occur after the first day of life. The clinical presentation of secondary subarachnoid hemorrhage is often dominated by the cause of the subarachnoid hemorrhage. In cases of idiopathic subarachnoid hemorrhage, the neonate appears healthy. The diagnosis is established by CT or MRI of the brain. In a neonate with seizures and subarachnoid hemorrhage, other causes for the seizures should be considered. The prognosis of a neonate with idiopathic subarachnoid hemorrhage is good. Subarachnoid hemorrhages require no treatment but careful follow-up is necessary due to the possibility of hydrocephalus. Seizures should be treated with antiepileptic drugs. More about... 251

Intraventricular and Intraparenchymal Hemorrhages
Intraventricular hemorrhage usually presents as lethargy or irritability. Seizures are uncommon but other types of pathological paroxysmal motor events often occur. Intraparenchymal hemorrhages are more frequent than intraventricular hemorrhages in neonates born at term. Seizures are a frequent presentation of intraparenchymal hemorrhages in fullterm neonates. More about... 251-255

Cerebral Infarction
Convulsions are the most common presenting sign of cerebral infarction in neonates. Focal motor deficit often persists after the convulsion stops. Cerebral arterial infarction may occur because of endomural, mural, or extramural abnormalities affecting a vessel. Endomural occlusions are either embolic or thrombotic. The source of the emboli is usually the heart or the placenta. Embolic strokes are frequentinneonateswith cyanotic heart disease because the venous blood bypasses the lungs (natural filter). Thrombosis results from trauma, coagulopathies (proteins C and S deficiencies), or polycythemia. More about... 253