optic nerve atrophy MP:0001059 MP:0001331 MPheno.ontology acquired diminution of the size of the second cranial nerve which is responsible for conveying visual information from the retina to the brain, associated with wasting as from death and reabsorbtion of cells, diminished cellular proliferation, decreased cellular volume, pressure, ischemia, malnutrition, reduced function or malfunction, or hormonal changes atrophic optic nerve atrophy of optic nerve abnormal optic nerve morphology