White matter

As a white substance (Latin substantia alba) is defined as the parts of the central nervous system, consisting of pathways (nerve fibers) exist. It is opposed to the gray matter. The white color is produced by the myelin sheaths of nerve fibers.

In the spinal cord the white substance of the gray outside is present and is macroscopically in anterior column ( anterior funiculus ), lateral funiculus ( funiculus lateralis) and dorsal column ( funiculus posterior) divided.

In the brain, the white matter is on the inside and is surrounded by the gray matter. In the white matter, however, are also areas with gray matter, which are accumulations of nerve cell bodies stored. This is referred to as core areas ( nuclei ).

White Matter Lesion

As white matter lesion (WML ) is called damage to the white matter, which occur quite frequently with increasing age in the population and associated with cognitive impairment and stroke. They are also known as white matter hyperintensities, as they appear as bright white spots on MRI scans. In the Rotterdam Scan Study of 1077 non- demented persons 60-89 years of age without WML were found in only 5%. 80 % had periventricular WML, which are associated with cognitive and psychomotor disturbances.

Histopathologically WML are described as gliosis, demyelination and axonal loss and diagnosed as leukoaraiosis or vascular dementia.

Gallery

Sagittal section of the brain: gray matter and white matter outside inside.

Credentials

• Central Nervous System
• Spinal cord
• Nervous tissue