OCT scans and multiple sclerosis

Here is My Question:
How many OCTs are necessary and over what stretch of time to rule demyelination in or out? I had an OCT 18 months ago which showed damage. I had another recently and when I asked about it my eye doctor just said really we can only get a picture of this over time and said he could not compare the new one to the one from 18 months ago because it did not make sense to do so. However my neurologist is interested in a repeat OCT. I am confused.

Here is my answer:
 
The question of when and how often to perform OCT depends on why the test is being ordered.
 
If you have a clear cut definite diagnosis of multiple sclerosis, there is not great evidence that you need to have annual repeat OCT scans.  However your neurologist may want to track the retinal nerve fiber thickness as a way of monitoring your MS.
 
I usually get repeat OCT scans in my patients who have either atypical cases of optic neuritis, a questionable diagnosis of multiple sclerosis or unexplained vision loss.
 
Some patients on an MS medication called Gilenya (fingolimod) have annual OCT scans of the macula to help monitor for a rare side effect (macular edema).
 
Sincerely,
 
Benjamin Osborne, MD
Associate Professor of Neurology and Ophthalmology
Director, Neuromyelitis Optica (NMO) Clinic
Director, Neuro-Ophthalmology Clinic
Associate Director of the NIH/Georgetown Neurology Residency Program
Medstar Georgetown University Hospital
3800 Reservoir Road, NW 7PHC
Washington, DC 20007