Optic Nerve Glioma – Causes, Symptoms, Diagnosis, And Treatment
What is optic nerve glioma?
Optic nerve glioma (optic glioma) is a brain tumor that grows in or around the optic nerve, which connects the eye to the brain. Optic nerve gliomas are rare and are the most common tumors of the optic nerve. Most of the optic nerve gliomas are noncancerous and slow-growing. This brain tumor mostly affects children before age 20.
What causes optic nerve glioma?
The cause of optic nerve gliomas is not known. What is known is there is a strong association between optic nerve glioma and neurofibromatosis Type 1.
What are the symptoms of optic nerve glioma?
Optic nerve glioma itself does not cause any symptoms. The symptoms are caused when the tumor grows and presses on the optic nerve and nearby structures.
The following are the symptoms:
- Outward bulging of one or both eyes
- Involuntary eyeball movement
- Vision loss in one or both eyes (starts with peripheral vision loss, eventually leading to blindness)
The affected child may show symptoms of diencephalic syndrome, which includes:
- Decreased memory
- Decreased brain function
- Daytime sleeping
- Delayed growth
- Loss of appetite and body fat
How is optic nerve glioma diagnosed?
The doctor will examine the eye and review the symptoms. The neurological examination may reveal vision loss in one or both eyes. The doctor may find swelling or scarring of the optic nerve, or paleness and damage to the optic disc.
The doctor may find increased pressure in the brain if the tumor penetrates deeper parts of the brain. There may also be signs of neurofibromatosis type 1.
The doctor may order the following tests:
- Head CT scan or MRI of the head
- Biopsy to confirm the tumor type
- Cerebral angiography
- Visual field tests during CT-guided biopsy or surgery
How is optic nerve glioma treated?
Treatment of optic nerve glioma depends on the size of the tumor and the health condition of the person. The goal of the treatment would be to cure the disorder, relieve symptoms, and improve vision. Treatment options include surgery, chemotherapy, or radiation.
Surgical removal of the tumor may cure some optic nerve gliomas. In many cases, a part of the tumor is removed to reduce the size of the tumor. Their reduced size keeps the tumor from damaging normal brain tissue around it.
Doctors may use chemotherapy in some children. Chemotherapy may be used when the tumor extends into the hypothalamus or if vision has been affected by the tumor’s growth.
Doctors recommend radiation therapy if the tumor keeps growing despite chemotherapy. It is also recommended when surgery is not possible.
Doctors may prescribe corticosteroids to reduce swelling and inflammation during radiation therapy, or if symptoms return.
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.