- Septum pellucidum
Infobox Brain
Name = Septum pellucidum
Latin =
GraySubject = 189
GrayPage = 840
Caption = Scheme of rhinencephalon. (Septum pellucidum visible at top center.)
Caption2 = Median sagittal section of brain. (Septum pellucidum visible at center.)
IsPartOf =
Components =
Artery =
Vein =
BrainInfoType = hier
BrainInfoNumber = 238
MeshName = Septum+Pellucidum
MeshNumber = A08.186.211.276.814
Dorlands = nine/20800743
DorlandsID = Septum pellucidum
The septum pellucidum (also called the septum lucidum) is a thin, triangular, vertical membrane that separates thelateral ventricle s of thebrain . It separates the anterior horn of the left and right lateral ventricles. It runs as a sheet from the corpus callosum down to thefornix . When the hemispheres are cut apart, the septum remains on one hemisphere, usually the left. The septum pellucidum is currently believed to have no particularly special functional importance.Layers
The septum pellucidum actually consists of two layers or "laminae" of both white and
gray matter , called the "laminae septi pellucidi".These layers are normally fused; however, in approximately one-tenth of humans, there is a slit-like cavity between them, referred to as
cavum septum pellucidum , cavum septi pellucidi, or "fifth ventricle" [DorlandsDict|two/000018335|Cavity of septum pellucidum] [cite journal | author = Love J, Hollenhorst R | title = Bilateral palsy of the sixth cranial nerve caused by a cyst of the septum pellucidum (fifth ventricle) and cured by pneumoencephalography | journal = Mayo Clin Proc | volume = 31 | issue = 2 | pages = 43–6 | year = 1956 | pmid = 13289891] . The last term has lost favor in recent years, as the space is usually not continuous with the ventricular system and does not containcerebrospinal fluid [cite journal | author = Alonso J, Coveñas R, Lara J, Piñuela C, Aijón J | title = The cavum septi pellucidi: a fifth ventricle? | journal = Acta Anat (Basel) | volume = 134 | issue = 4 | pages = 286–90 | year = 1989 | pmid = 2741657] . Indeed "fifth ventricle" has been used for other purposes in recent years. [cite journal | author = Liccardo G, Ruggeri F, De Cerchio L, Floris R, Lunardi P | title = Fifth ventricle: an unusual cystic lesion of the conus medullaris | journal = Spinal Cord | volume = 43 | issue = 6 | pages = 381–4 | year = 2005 | pmid = 15655569 | doi = 10.1038/sj.sc.3101712] .Location
The septum pellucidum is located in the midline of the brain, between the two
cerebral hemisphere s. It is attached superiorly (above), anteriorly (in front), and inferiorly (below) to thecorpus callosum , the large collection of nerve fibers that connect the two hemispheres.Inferiorly and posteriorly (in back), it is attached to the anterior part of the fornix.
On either side are the two lateral ventricles, pockets of cerebrospinal fluid within the cerebral hemispheres.
Pathology
Absence of the septum pellucidum or corpus callosum, caused by
mutation s in the Gene|HESX1gene , is associated withsepto-optic dysplasia . This may result in hypothalamic dysfunction andhypopituitarism , as well as problems of vision, coordination, and intelligence, among other abnormalities.One famous reference to an abnormality of the septum pellucidum would be the movie
Rocky V . In the movie, the main characterRocky Balboa is forced to retire due to brain damage sustained throughout his career.
=AdditionalReferences
* Gray, Henry & Clemente, Carmine D. (1984). "Gray's Anatomy of the Human Body" (30th ed.). New York: Lippincott Williams & Wilkins.
* Kasper, Dennis L.; Braunwald, Eugene; Fauci, Anthony S.; Hauser, Stephen L.; Longo, Dan L.; Jameson, J. Larry; & Kurt J. Isselbacher, (Eds.) (2004). "Harrison's Principles of Internal Medicine" (16th ed.). New York: McGraw-Hill.
External links
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