5% of all childhood intracranial tumors are optic pathway gliomas1.
Generally low grade tumors, but follow a variable clinical course.
Most prevalent in young children:
- 25% of all cases occurring before 18 months
- 50% before 5 years
- 75% within the first decade of life.
The mean age of presentation in one series was just over 8 years of age.
These tumors may involve many different parts of the optic pathway:
- 20-25% of tumors involve the optic nerves alone
- 20-40% involve the optic chiasm (alone or in combination with cranial nerves)
- 30-60% involve both the optic chiasm and the hypothalamus
Table : Incidence of various features of optic nerve gliomas.
Feature |
Incidence |
Proportion of pediatric intracranial tumors |
5% |
Before 18 months |
25% |
Before 5 years |
50% |
Before 10 years |
75% |
Median age |
5 years |
Involving optic nerves alone |
20-25% |
Involving optic chiasm (and/or optic nerves) |
20-40% |
Involving optic chiasm and hypothalamus |
30-60% |
Racial bias |
None |
Gender bias |
Slight female predominance |
Neurofibromatosis (NF)
- Associated with the development of optic pathway gliomas
- Type 1 NF is an autosomal dominant disorder characterized by abnormalities in ectodermal tissue growth.
- 25-40% of optic gliomas occur in children with NF-1, and of children with NF-1, about 10% develop optic gliomas.
