Topics

Topic

design image
White matter of cerebellum (Arbor vitae)

The arbor vitae, meaning “tree of life,” is the white matter of the cerebellum that forms a branching, treelike structure within the cerebellar hemispheres and vermis. It consists of myelinated axonal fibers connecting the cerebellar cortex (gray matter) to the deep cerebellar nuclei and to other parts of the central nervous system, including the brainstem and spinal cord. The arbor vitae is responsible for coordinating motor control, balance, and fine-tuning voluntary movements.

The branching pattern of the arbor vitae increases the surface area for cortical input and output, ensuring efficient communication between the cerebellar cortex and deep nuclei. The white matter is surrounded by cerebellar gray matter (cortex) and is subdivided into central medullary cores extending into the cerebellar folia.

Function

  • Transmits motor signals from the cerebellar cortex to deep nuclei

  • Facilitates coordination, balance, and fine motor control

  • Connects cerebellum to brainstem and spinal cord pathways

  • Supports learning and timing of motor activities

  • Integrates sensory feedback with motor output

Synonyms

  • Arbor vitae cerebelli

  • Cerebellar white matter

  • Central medullary core of cerebellum

MRI Appearance

T1-weighted images:

  • The arbor vitae appears as intermediate to high signal intensity (whitish) compared to the surrounding gray matter, reflecting myelinated fibers

  • The branching pattern is clearly seen in sagittal and coronal planes

  • Pathology such as demyelination or infarction appears as hypointense or heterogeneous signal

T2-weighted images:

  • Arbor vitae is intermediate signal, slightly hypointense relative to gray matter

  • Gray matter (cerebellar cortex) is relatively hyperintense, producing a treelike contrast

  • Edema, infarcts, or demyelination may appear hyperintense

STIR (Short Tau Inversion Recovery):

  • Normal arbor vitae remains low to intermediate signal

  • Edematous or inflamed white matter appears bright (hyperintense), helpful in acute cerebellar infarcts or inflammatory conditions

T1 Post-Contrast (Gadolinium-enhanced):

  • Normal arbor vitae shows no significant enhancement

  • Pathological conditions such as tumor infiltration or active inflammation demonstrate focal or diffuse enhancement along white matter tracts

CT Appearance:

  • Arbor vitae appears as slightly hyperdense branching structures within the cerebellum

  • Surrounding gray matter is slightly less dense, producing the classic treelike appearance

  • CT is useful for detecting hemorrhage, calcification, mass effect, or structural deformities

MRI images

White matter of cerebellum (Arbor vitae) mri sag image -img-00000-00000

MRI images

White matter of cerebellum (Arbor vitae)