Lateral geniculate nucleus

Last revised by Elmira Hassanzadeh on 23 Oct 2024

The lateral geniculate nucleus, also known as the lateral geniculate body, is one of the thalamic nuclei. It acts as the principal relay nucleus for the visual system and, as such, it is conveniently located at the termination of the optic tract.

Together with the medial geniculate body, it forms the metathalamus.​

The lateral geniculate body is supplied by the lateral posterior choroidal artery and the anterior choroidal artery 5.

Microscopically the lateral geniculate nucleus appears as alternating white and grey matter layers. The four dorsal parvocellular layers are primarily involved in the perception of color and form, whereas the two ventral magnocellular layers are concerned with the perception of movement and depth 3.

The lateral geniculate nucleus is not easily visualized on routine T1 or T2 weighted MRI imaging as it is small and is composed of alternating layers of white and grey matter reducing inherent contrast 3. It is best seen on proton-density images 3,4.

Even though the lateral geniculate nucleus is difficult to see, it can be localized anatomically by following the optic tract posteriorly until it fades out. This occurs at the level of the superior colliculi on axial imaging (AC-PC line), just lateral to the medial geniculate nucleus, where it is thus located between three white matter tracts: optic tract anteriorly, optic radiation posterolaterally and posterior limb of the internal capsule anteromedially 3,4.