Optic pathway glioma has 3 broad types:

-Childhood benign tumors associated with NF1.

-Childhood benign tumors not associated with NF1.

-Adult tumors that are typically malignant.

Imaging findings:

-Best diagnostic tool: Fusiform optic nerve mass with variable posterior pathway involvement.

-Ranges from no enhancement to intense homogenous enhancement.

-Calcification is rare (unlike optic sheath meningioma).

-Bilateral intraorbital lesions indicate NF1.

-Associated neuroimaging findings if NF1 is present: Brain T2 foci, other CNS tumors, sphenoid dysplasia.