Pressure in the sagittal sinus during intracranial hypertension in man

Abstract

✓ Intracranial pressure (ICP) and sagittal sinus pressure (SSP) were measured simultaneously in 12 patients with brain tumors and secondary intracranial hypertension (ICH). In nine, the mean SSP was largely unaffected by changes in ICP. In three, SSP changed with the ICP. In all but one patient, the ICP remained higher than SSP and, as the ICP increased, the difference between the two also increased. Sinograms performed during ICH demonstrated partial collapse of the sinuses in some patients and not in others. The mean SSP in adults with brain tumors appears to respond unpredictably to changes in ICP. Since the rate of cerebrospinal fluid drainage depends upon the gradient between ICP and SSP, intracranial spatial compensation is probably influenced by the response of SSP to ICP. Individuals with gradients that rapidly increase because their sinuses do not collapse probably compensate more rapidly than those whose sinuses do collapse. This assumed difference in the rate of spatial compensation may account for some of the variability of the ICP response to an enlarging intracranial mass or a change in cerebral blood volume.

Intracranial Venous Hemodynamics in Patients With Midline Dislocation Due to Postischemic Brain Edema

“…A functionally relevant stenosis in the vein of Galen, however, will cause the flow velocities in the straight sinus to drop again. A similar partial collapse of dural sinus structures was reported for the transverse sinus and the middle portion of the superior sagittal sinus in patients with space-occupying edema due to intracerebral tumors 17 and subdural and epidural hematoma. 19 In all cases, partial collapse was confirmed by direct sinography with normalization after treatment.…”

Cerebral Venous Flow Velocity Predicts Poor Outcome in Subarachnoid Hemorrhage

“…Contrary to increase of flow velocity within the straight sinus and the vein of Galen, flow velocity within BVR was reduced. 27 This phenomenon might best be explained by partial compression of the rigid sinuses with consecutive stenosis, 28,29 which results in reduced flow velocity in the preceding vessel. These findings have been shown in SAH as well as in brain trauma 30,31 and are in accordance with our data.…”

Cranial Venous Outflow Obstruction and Pseudotumor Cerebri Syndrome

“…In one patient who demonstrated an increase in SSS pressure with increased CSF pressure there was partial collapse of the sagittal and transverse sinuses at 40 mmHg. In addition Martins et al [110] noted that 3 patients had pressure waves during recording. In 2 patients the duration was less than 1 minute.…”

“…Martins et al [110] monitored CSF pressure and SSS pressure simultaneously in 12 patients undergoing ventriculography who were subsequently found to have cerebral tumours. In 9 patients SSS pressure was not related to CSF pressure and remained below 14 mmHg in the presence of spontaneous or artificial increases in CSF pressure up to 75 mmHg.…”