OCT eye exam

Question

Hey all!  Does anybody know anything about the OCT eye exam (optical coherence tomography)?  

I had an OCT done on Monday, and it came up abnormal, so now (well, in a month or two!) I'm off to a neuro-ophthalmologist...  I just don't really know what to expect!  

I had the "retinal nerve fiber layer" exam done, and it showed thinning in both of my eyes.  I know this usually indicates glaucoma, but I'm 22, and in any case I haven't ever had any blindspots or dimming or anything like that, and I think my visual field exam came out totally normal...  I just get the feeling that the OCT typically isn't used in diagnosing MS, so I'm just feeling kind of confused!  Does anybody know anything about this?  Has anyone else had this done?

Oh, I had the OCT test done because I've had three completely normal MRIs, but an abnormal VEP and lumbar puncture (with excess white cells and 10 oligoclonal bands unique to the CSF).  The MS specialist I saw said he was ordering to the OCT to show that my VEP results were a false positive - this is all so frustrating!  

Well, anyway, I really appreciate any input that you guys may have.  Hope you all are having a great start to the weekend - hope it's good sunny spring weather for you all!

twopack · Answer

This is an updated reprint of the article ess cited above.

http://www.sciencedaily.com/releases/2012/10/121017091256.htm

essdipity · Answer

This is a good layperson's explanation of the use of OCT to follow MS patients---

http://www.sciencedaily.com/releases/2007/10/071015193523.htm

ess

PastorDan · Answer

I'm wondering about a false negative in the VEP I had last year, because I've never received a satisfactory explanation about the SSEP done in the same sitting being uninterpretable.  Thus, I'm hesitant to put much faith in that lab.

Wow, 10 unique O-bands and this "MS specialist" still thinks you don't have MS?  I think Doc Q is right (again); this guy idolizes the MRI.  Sounds like he's lost without it.

Now, how exactly does the OCT work?  Is it an optical process, x-rays, magnetic fields, or something else?  The "tomography" with which I'm familiar is an X-ray process, but that was on my kidneys.  I think that's the "T" in CT scan, too.

essdipity · Answer

My neuro told me last time that if VEP is abnormal, OCT will always be abnormal as well. This was at Hopkins, where OCT was first used in conjunction with MS, so I hope he knows what he's talking about. Because I did have an abnormal VEP in my right eye, he therefore declined to order an OCT test. Bummer for me, as I was hoping that might show progress of the disease.

I've never heard of a false positive in VEP, and am wondering how that's even possible. Does anyone know?

ess

Celery47 · Answer

Dear Quix and Jen, thank you so much for writing! I was feeling so, so sad today, just thinking of the prospect of going to another neurologist who's probably going to tell me, "nothing neurological here!" Turns out, all I needed were the words "weenie neuro" to feel completely like myself again :) Hahaha, thanks so much for making me laugh, Quix! And thanks both of you for your explanations.

Quixotic1 · Answer

Jen is correct.  OCT has been standardized for use in MS for "followup", but not for diagnosis.  People with MS suffer atrophy of the brain much more steadily and much earlier than the general healthy population.  It turns out that the optic nerve atrophies right aong with the rest of the brain.  What this means is thay we all suffer optic neuritis, whether or not we have symptoms of it.

They have found that they can do the very quick and non-painful, noninvasive OCT in lieu of doing all of the followup MRIs.  The thinning of the retinal nerve fiber layer at the very edges of the optic disc can show the neurologists how much brain tissue is being destroyed by the disease.

Now, what this implies, is that everyone gets optic neuritis at some point in their disease and that it is often silent (no symptoms).  I suspect that a lot of neuros cannot handle this info or know what to do with it.  It throws all of the "rules" about ON out the window, like there has to be pain with movement, or loss of vision, or flashing lights for it to be ON.

I had OCT a year and a half ago, having never had any symptoms of ON.  But, yet I have mild atrophy on the left and right at the low borderline on the right.  I have a normal eye exam.

I'm sure that the field will start looking at OCT in terms of diagnosis, but that has not been done yet.  However, your abnormal results will likely be view as probable indicators of MS.

I hope the weenie neuro squirms, though he would never let you know it.  It also shows that he does not understand the emerging role of OCT in the care of MS.  I also agree with Jen that your neuro most likely worships the MRI as "all-revealing."

Quix

jensequitur · Answer

Optical Coherence Tomography is a brand new test used in diagnosing MS.  It's much more reliable than the usual MRI + LP and EEG tests, because it looks at the nerve fiber of the eye.  All white matter is affected by MS, and the optic nerve will show thinning and atrophy with MS disease activity.

It sounds like your MS specialist was wrong, and your VEP results were accurate.  MRIs are just not as reliable as the neurologist wants them to be.