Infectious or noninfectious venous thrombosis of the sagittal sinus. Spontaneous and secondary forms occur. Associated conditions include DEHYDRATION; SEPSIS; THROMBOPHILIA; $CRANIOCEREBRAL TRAUMA$; and NEUROSURGICAL PROCEDURES. Affected individuals may present with or develop HEADACHE; neck pain; PAPILLEDEMA; SEIZURES; INTRACRANIAL HYPERTENSION; venous CEREBRAL INFARCTION; INTRACRANIAL HEMORRHAGES; hemiparesis; and other focal neurologic deficits. (From Adams et al., Principles of Neurology, 6th ed, p612).