The cerebral aqueduct (aqueduct of the midbrain, aqueduct of Sylvius, Sylvian aqueduct, mesencephalic duct) is a small, narrow tube connecting the third and fourth ventricles of the brain. The cerebral aqueduct is a midline structure that passes through the midbrain. It extends rostrocaudally through the entirety of the more posterior part of the midbrain. It is surrounded by the periaqueductal gray (central gray), a layer of gray matter.
Congenital stenosis of the cerebral aqueduct is a cause of congenital hydrocephalus.
Function
The cerebral aqueduct acts as a canal that passes through the midbrain. It connects the third ventricle with the fourth ventricle so that cerebrospinal fluid (CSF) moves between the cerebral ventricles and the canal connecting these ventricles.
Clinical significance
Aqueductal stenosis, a narrowing of the cerebral aqueduct, obstructs the flow of CSF and has been associated with non-communicating hydrocephalus. Such narrowing can be congenital, arise via tumor compression (e.g. pinealoblastoma), or through cyclical gliosis secondary to an initial partial obstruction.
Additional images
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File:Gray710.png|Transverse section through mid-brain; number 2 indicates the cerebral aqueduct.
File:Gray711.png|Transverse section of mid-brain at level of inferior colliculi.
File:Gray712.png|Transverse section of mid-brain at level of superior colliculi.
File:Periaqueductal_MRI.PNG|MRI section of mid-brain.
File:Gray720.png|Median sagittal section of brain.
File:Gray734.png|Scheme showing relations of the ventricles to the surface of the brain.
File:Slide1qq.JPG|Cerebral aqueduct
File:Slide7qq.JPG|Cerebral aqueduct
File:Slide2HOM.JPG|Cerebral peduncle, optic chasm, cerebral aqueduct. Inferior view. Deep dissection.
File:Slide3HOM.JPG|Cerebral peduncle, optic chasm, cerebral aqueduct. Inferior view. Deep dissection.
File:Slide2ERV.JPG|Cerebrum. Inferior view. Deep dissection
</gallery>
See also
- List of regions in the human brain