The pons is an approximately 2cm long “knob-like” process located deep in the middle of the brain.
One can visualize the pons as a box…
The pons itself is divided into a back (medically called dorsal) part and a front (medically called ventral) part. The back part is often called the Pontine Tegmentum whereas the front part is called the Ventral or Basal Pons. There are 4 paired cranial nerves (one on the left and one on the right) that start in the pons.
The pontine tegmentum is against the 4th ventricle and contains an origin of 4 cranial nerves (5th, 6th, 7th and 8th nerve), the reticular activating system, ascending/descending nerve tracts, as well as other nuclei.
The ventral pons consists of nerve fiber tracts going up and down as well as across the area. It acts as a massive relay station connecting the cerebral cortex to the cerebellum on the other side through a structure called the cerebellar peduncles.
The cranial nerves are nerves that control the special senses and the movement/sensation of the head and neck.
Four sets of cranial nerves come from the pons.
5th – Trigeminal nerve
6th – Abducens nerve
7th – Facial nerve
8th – Vestibulocochlear nerve
Allowing nerve bundles to travel back and forth from the cerebrum to the cerebellum as well as nerve bundles to and from the body. Essentially all information from the brain to the body or vice versa must go through someplace in the brainstem.
The cranial nerves that originate in the pons are the:
The cerebellar peduncles (also called brachium pontis) are the nerve superhighway from the pons to the cerebellum.
The area above the blue is the tegmentum.
The area below the blue is the ventral pons.
The crossing fibers in the vental pons continue to the sides to form the cerebellar peduncles.
The blood to the pons is supplied by the pontine arteries. These are small arteries that branch off the basilar artery.
Used with permission from Just One More Day
Different Brainstem Glioma Locations
A- Tectal Glioma
B- Focal midbrain tumor
C- Focal intrinsic pontine glioma
D- Doral/exophytic glioma
E- Diffuse Intrinsic Pontine Glioma
F- Focal medullary glioma
G- Cervicomedullary glioma