Subarachnoid cisterns

Subarachnoid cisterns
The subarachnoid cisterns are spaces formed by openings in the subarachnoid space, an anatomic space in the meninges of the brain. The space is situated between the two meninges, the arachnoid mater and the pia mater. These cisterns are filled with cerebrospinal fluid (CSF).
Structure
Although the pia mater adheres to the surface of the brain, closely following the contours of its gyri and sulci, the arachnoid mater only covers its superficial surface, bridging across the gyri. This leaves wider spaces between the pia and arachnoid and the cavities are known as the subarachnoid cisterns.
Although they are often described as distinct compartments, the subarachnoid cisterns are not truly anatomically distinct. Rather, these subarachnoid cisterns are separated from each other by a trabeculated porous wall with various-sized openings.
Cisterns
There are many cisterns in the brain with several large ones noted with their own name. At the base of the spinal cord is another subarachnoid cistern: the lumbar cistern which is the site for a lumbar puncture.
Some major subarachnoid cisterns:
Cisterna magna also called cerebellomedullary cistern - the largest of the subarachnoid cisterns. It lies between the cerebellum and the medulla oblongata. It receives CSF from the fourth ventricle via the median aperture (foramen of Magendie). The cisterna magna contains:
The vertebral artery and the origin of the posterior inferior cerebellar artery (PICA)
The ninth (IX), tenth (X), eleventh (XI) and twelfth (XII) cranial nerves
Pontine cistern. Surrounds the ventral aspect of the pons. It receives CSF via the paired lateral apertures. It contains:
The basilar artery and the origin of the anterior inferior cerebellar artery (AICA)
The origin of the superior cerebellar arteries
The sixth (VI) cranial nerve
Interpeduncular cistern. It is situated at the base of the brain, between the two cerebral peduncles of midbrain and dorsum sellae and continuous below with the pontine cistern and superiorly with the chiasmatic cistern. It contains:
The optic chiasm
The bifurcation of the basilar artery
Peduncular segments of the posterior cerebral arteries (PCA)
Peduncular segments of the superior cerebellar arteries
Perforating branches of the PCA
The posterior communicating arteries (PCoA)
The basal vein
The third (III) cranial nerve, which passes between the posterior cerebral and superior cerebellar arteries
Cerebellopontine angle cistern. It is situated at the cerebellopontine angle – the lateral angle between the cerebellum and the pons. It contains:
The seventh (VII) and eighth (VIII) cranial nerves
The anteroinferior cerebellar artery (AICA)
The fifth (V) cranial nerve and the petrosal vein
Quadrigeminal cistern - It is situated dorsal to the midbrain. Thin, sheet-like extensions of the superior cistern that extend laterally about the midbrain, connecting it to the interpeduncular cistern. Ambient cistern may also refer to the combination of these extensions and the superior cistern. It is composed of a supratentorial and an infratentorial compartment. It contains:
The great cerebral vein
The posterior pericallosal arteries
The third portion of the superior cerebellar arteries
Perforating branches of the posterior cerebral and superior cerebellar arteries
The third portion of the posterior cerebral arteries
Its supratentorial portion contains:
The basal vein
The posterior cerebral artery
Its infratentorial portion contains:
The superior cerebellar artery
The fourth (IV) nerve
Crural cistern. It is situated around the ventrolateral aspect of the midbrain. It contains:
The anterior choroidal artery
The medial posterior choroidal artery
The basal vein
Carotid cistern. It is situated between the carotid artery and the ipsilateral optic nerve. It contains:
The internal carotid artery
The origin of the anterior choroidal artery
The origin of the posterior communicating artery
Cistern of lateral cerebral fossa. It is situated in the fissure between the frontal and temporal lobes. It contains:
The middle cerebral artery
The middle cerebral veins
The fronto-orbital veins
Collaterals to the basal vein
Cistern of lamina terminalis. It is situated just rostral to the third ventricle. It contains:
The anterior cerebral arteries (A1 and proximal A2)
The anterior communicating artery
Heubner's artery
The hypothalamic arteries
The origin of the fronto-orbital arteries
Lumbar cistern. It extends from the conus medullaris (L1-L2) to about the level of the second sacral vertebra. It contains the filum terminale and the nerve roots of the cauda equina. It is from the lumbar cistern that CSF is withdrawn during a lumbar puncture.
It is of clinical significance that cerebral arteries, veins and cranial nerves must pass through the subarachnoid space, and these structures maintain their meningeal investment until around their point of exit from the skull.
See also
Subarachnoid hemorrhage
References
Nolte, J (2002) The Human Brain, 5th edition. , 87
Meninges