Cerebrospinal Fluid

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Section III. Cisterns

CSF cisterns are filled with CSF that has exited the ventricular system. The cisterns are important areas prone to accumulation of blood with subarachnoid hemorrhage and granulomatous pathology such as sarcoidosis or tuberculous basilar meningitis. Careful assessment for cistern effacement as an indicator of intracranial mass effect is an important component of brain imaging interpretation.

Vascular/CN components.

Again, inner arachnoid membrane.....

Axial Image of Suprasellar Cistern and Key Adjacent Structures


Sagittal Image of Suprasellar Cistern

The suprasellar cistern can be assessed on the midline sagittal image. Generalized effacement of this cistern can be detected by decreased distance between the optic chiasm and pituitary gland and decreased mammillopontine distance.

Subarachnoid Hemorrhage in Posterior Suprasellar/Interpeduncular Cistern

Patient with a small amount of spontaneous subarachnoid hemorrhage in the posterior suprasellar/interpeduncular cistern. No aneurysm found. This can be categorized as a perimesencephalic SAH pattern, which generally has a better outcome than aneurysmal SAH patterns.

Star-Shaped Suprasellar Cistern

Recall that the medial stem of the Sylvian fissure divides the basal frontal and basal temporal lobes, extending medially to terminate as one of the points of the 'star-shaped' suprasellar cistern. Note the M1 segments of the MCA (hyperintense vessels) in the MCA cisterns on this T1 MPRAGE image. The other points are the crural cisterns and the anterior interhemispheric fissure (which contains CSF). The interpeduncular cistern could also be considered a 6th point.

The CSF cisterns are divided into components by the inner arachnoid membranes, most of which are not well seen on MRI.

Specific Cisterns of the Suprasellar Region

More detailed depiction of the cisterns within and adjacent to the suprasellar region. These cisterns are often separated by a series of inner arachnoid membranes.

Optic Nerve Glioma of the Chiasm in NF-1


The location of key neurovascular structures can be defined by the cisterns they traverse.



Olfactory Cistern

The olfactory cistern lies at the base of the olfactory sulcus. It contains the olfactory tract of cranial nerve I and the orbitofrontal artery (the first major ACA branch typically arising near the proximal A2 segment.

Vessels in Cisterns and Ventricles

The cistern of the lamina terminalis and pericallosal cisterns contain important vessels. The internal cerebral veins form at the foramen of Monro and course posteriorly between the leaves of the velum interpositum along the roof of the 3rd ventricle.