Every time I've had an optic neuritis issue, a visual fields test has been done in addition to the eye exam.

You watch a dot of light that moves around on the screen and you signal when you're seeing the dot. Then your visual fields are plotted on a chart. They look for "holes" or "blind spots" in your visual field, and these can show up in either central or peripheral vision, or both.

Another test that can reveal optic neuritis is the visual evoked potentials test. You stare at a checkerboard pattern for a while. This test is usually ordered and done by a neurologist, not an ophthalmologist.

If the doctor looks into your eyes, the optic nerve can be visible, and some abnormalities in it can indicate optic neuritis but I'm fairly sure that these other tests are done to establish that diagnosis.

Your ophthalmologist was willing to put your case in the hands of the neurologist, who might want to order these tests.

If you aren't having eye symptoms, there may be no reason to do further tests.