Flow quantification in the superior sagittal sinus using magnetic resonance.

To date, the intracerebral veins and venous sinuses have not been amenable to noninvasive study. We describe a magnetic resonance (MR) technique using "bolus tracking" for rapid imaging and measurement of cerebral venous flow. We specifically applied the technique to the superior sagittal sinus, but it can be used for evaluation of other cerebral venous structures. In 10 healthy subjects and 21 patients referred for MR brain studies, mean flow was 420 ml/min. There was a significant inverse correlation between blood flow and age. There were dynamic changes in cerebral blood flow (CBF) during hyperventilation and hypercapnia. Since the cerebral cortex drains almost exclusively to the superior sagittal sinus, these flow measurements represent an index of global CBF. MR flow quantification provides a new means for assessing dynamic changes in CBF, and may prove useful for monitoring the effects of various disease processes and pharmaceutical agents on CBF.