Hi, what's the difference between benign cyst and benign tumor on optic nerve? thank you.

Cyst & tumor differ: A cyst is defined as an open space (sac) with an epithelial lining. This space may be filled with fluid, cellular debris, empty, etc. In general, a tumor is a solid growth, but may have cystic components. They can be composed of many different cell types. In this case, both are benign, but being on the optic nerve, they could still cause problems due to compression.