This is the optic nerve of one of my favorite patients. She has severe glaucoma with visual field loss. She is quite young and so must be treated very aggressively. Unfortunately she recently became sensitive to one of the most common glaucoma drops. But this can be managed with other options.
The crater in the middle of the optic nerve is called the optic “cup”. The worse the glaucoma the deeper the cup. This is a very deep cup. The picture really doesn’t do it justice because you would have to see it in 3-D.