Brain Tumors down arrow

Home > Disclaimer > Optic Nerve Glioma

 

Optic Nerve Glioma

 

 

Classification

Optic pathway tumors are generally classified according to their location along the optic pathway.

 

This classification correlates highly with:

  • The appropriate treatment for the disease
  • Symptoms associated with the tumor
  • Patient prognosis

 

The three major categories are:

    • Optic nerve gliomas
    • Chiasmatic gliomas
    • Chiasmatic/ hypothalamic gliomas 

Optic nerve gliomas can involve one or both optic nerves. 

If a child has bilateral tumors, then it is very likely that the child has NF-1.

 

Characteristics of Optic Nerve Gliomas:

Optic Nerve Gliomas

Areas involved
  • May be unilateral or bilateral

Age
  • Usually <5 years (when not associated with NF-1)

Symptoms
  • Asymptomatic
  • Proptosis
  • Optic atrophy
  • Impaired visual acuity

Clinical Course
  • Variable, but generally non-progressive

MR scan

Tumor is generally:

  • Small
  • Well circumscribed
  • Homogeneous enhancement with gadolinium

Biopsy

Not necessary for diagnosis

Principles of Therapy
  • Initial close follow up
  • Active intervention at time of progression
  • If there is no remaining vision at the time of presentation, surgical resection recommended
  • To preserve useful vision, chemotherapy can be used for younger children and radiation therapy (RT) for older children

Long-term survival
  • Approaching 100%

 

Characteristics of Chiasmatic Gliomas:

Chiasmatic Gliomas

Affected areas
  • Optic chiasm
  • One or both optic nerves

Symptoms
  • Loss of visual acuity
  • Temporal field defects

Clinical course
  • At age < 5 years tumor may progress within a few months of diagnosis

MR Scan

Tumor is generally:

  • Small
  • Well circumscribed
  • Homogeneous enhancement with gadolinium

Biopsy
  • Generally unnecessary

Principles of Therapy
  • Period of surveillance after diagnosis
  • Same use of chemotherapy and RT as with optic gliomas when progression is observed

Long-term survival
  • 90-100%

 

Characteristics of Chiasmatic/Hypothalamic Gliomas:

Chiasmatic/Hypothalamic Gliomas

Affected areas
  • Originate in optic chiasm
  • Extends to hypothalamus
  • May fill the 3rd ventricle

Symptoms

Early symptoms include:

  • Nystagmus
  • Impaired visual acuity
  • Visual field deficits

Late symptoms include:

  • Signs of raised intracranial pressure (hydrocephalus)

Clinical Course

Generally:

  • Large tumor
  • More aggressive than other varieties

MRI

Biopsy

Treatment
  • Treatment of hydrocephalus with shunt
  • Surgical resection if possible(rarely able to achieve total resection)
  • Post-operative adjuvant therapy (chemotherapy and or radiation therapy for disease progression)

Long-term survival
  • 50-80%

Staging

  • No generally accepted staging system for optic pathway gliomas. 
  • Low-grade gliomas and tend to be slow-growing.
  • Large infiltrating lesions may invade the hypothalamus, but distinctions between optic and hypothalamic tumors are not usually of any clinical relevance. 

Back to top

Next