Cerebellar Anatomy and Blood Supply Quiz

Cerebellum Anatomy

• The cerebellum lies in the posterior cranial fossa and is the largest part of the hindbrain.
• It is located posterior to the 4th ventricle, pons, and medulla.
• The cerebellum consists of two cerebellar hemispheres connected by the vermis.

Connections to Brainstem

• The cerebellum is connected to the brainstem by peduncles:
  • Superior cerebellar peduncle connects to the midbrain.
  • Middle cerebellar peduncle connects to the pons.
  • Inferior cerebellar peduncle connects to the medulla.

Fissures and Lobes

• The cerebellum has three fissures:
  • Fissure prima separates the anterior lobe from the middle lobe.
  • Postero-lateral fissures separate the flocculo-nodular lobe from the middle lobe.
  • Horizontal fissure separates the superior and inferior borders of the hemisphere.
• The cerebellum has three main lobes:
  • Anterior lobe: lies in front of the fissure prima and includes the lingula.
  • Middle lobe: extends from the fissure prima to the postero-lateral fissure and includes the tonsil.
  • Flocculo-nodular lobe: consists of the nodule of the vermis and two flocculi.

Functional Division

• The cerebellum is functionally divided into:
  • Archi-cerebellum (vestibular cerebellum): includes the flocculo-nodular lobe and the lingula, and is related to equilibrium and maintenance of head position.
  • Paleo-cerebellum (spino-cerebellum): includes the anterior lobe minus the lingula, and is connected to the spinal cord, concerned with muscle tone.
  • Neo-cerebellum: includes the middle lobe, and is connected to the cerebral cortex via the ponto-cerebellar pathway, concerned with sequence and timing of movement.

Zones and Nuclei

• The cerebellum is divided into longitudinal zones:
  • Vermal zone: occupies the vermis.
  • Intermediate (or paravermal) zone: lies on each side of the vermis.
  • Lateral zone: lies just lateral to the intermediate zone.
• The inner white matter of the cerebellum contains four intracerebellar nuclei:
  • Dentate nucleus.
  • Emboliform nucleus.
  • Globose nucleus.
  • Fastigial nucleus.

Blood Supply

• The cerebellum is supplied by:
  • Superior cerebellar artery (from basilar artery).
  • Anterior inferior cerebellar artery (from basilar artery).
  • Posterior inferior cerebellar artery (from vertebral artery).

Pathways

• From cerebral cortex:
  • Cortico-pontino-cerebellar pathway.
  • Cerebro-olivo-cerebellar pathway.
  • Cerebro-reticulo-cerebellar pathway.
• From spinal cord:
  • Anterior spino-cerebellar tract.
  • Posterior spino-cerebellar tract.