Large Exophytic Dorsal Pontine Lesion With Hydrocephalus

Gliomas are a broad category of brain tumors that arise from glial cells, playing various supportive roles in the brain. Gliomas of the brain stem form immediately above the back of the neck, connecting the base of the brain to the spinal cord. 

The brain stem is divided into three sections:

• The midbrain, which grows into its stem, emerges from the brain’s center.
• The pons is a region of the brain that lies between the midbrain and the medulla oblongata. The majority of brainstem gliomas start in this area of the brain stem.
• The top of the spinal cord forms the medulla oblongata, which spreads out near the brain base.

Dorsally exophytic gliomas are tumors in the brainstem that protrude into the fourth ventricle or the cerebellopontine angles. Because the tumor inhibits the passage of cerebrospinal fluid (CSF), they commonly induce hydrocephalus (a build-up of fluid in the brain).

The majority of these tumors form in the pons region of the brain stem, making surgical treatment extremely difficult. A portion of a localized brainstem glioma can sometimes be excised. However, surgery for a brainstem glioma is frequently deemed too challenging due to the danger of side effects.

If hydrocephalus is present, patients may be offered a cerebral spinal fluid (CSF) shunt to help alleviate the symptoms. The shunt is implanted during a neurosurgery procedure and functions to drain excess fluid from the brain.