A astrocytoma (excluding glioblastoma) that involves the cranial nerve II. The disease is MONDO_0003234 (optic nerve astrocytoma). Also known as: astrocytic tumor of optic nerve, astrocytic tumour of optic nerve, astrocytoma (excluding glioblastoma) of cranial nerve II, astrocytoma of optic nerve, astrocytoma of the optic nerve, cranial nerve II astrocytoma (excluding glioblastoma).