What role do the SSEP and BAER Tests have in diagnosing MS?

[Sarahsmom46]

I got my SSEP (somatosensory evoked poetntial) and BAER another tests they did together and the doctor only said the results were "OK" not normal not abnormal, just ok.  Now, I have an inquiring mind and like to see stuff in writing, but I somehow walked out of his office and forgot to get a copy of the results.  So, here I am asking you very kind, smart, and generous friends if you have had any of these tests and what types of results did you get?  What roles do these tests have on diagnosing MS?   I'll share the results when I get the copy of the reports if anyone is interested.  

Julie

[wissel]

I had 2 DSSEP Tests: 1 for upper, 1 for Lower.  The neuro's office when questioned, re: the price (i had no insurance).  "How much?" I asked.They said, with insurance it's "$7,500.00 for upper and $7,500. for lower".  I said, I can't afford that.  They con't., "If you don't have insurance it's "$300. for upper, $325. for lower.  They con't., "The insurance company pays the rest".
Question:  Does this fee 'scale' sound familiar to any who've had a DSSEP Tests?  This fee seems quite high.  Especially after hearing some of you say, "The neuro doesn't give much credence to them anyway".
Wow, the neuro's offices that serve-up these tests really make a profit don't they?  Am I wrong?  
Plus, once I said at a neuro visit, "I also have tingling and numbness on the tops of my right and left thighs".  He said, "No, you don't".  Still makes me cringe.   Thanks, I hope you all feel gr8 and are at the top, or at least near the top of where you'd like to be.  Don't give up.  

[LATW]

The VEP is not painful.  It can be difficult to get through the whole thing if you are having problems with your eyes though.  

My VEP was the only abnormal one of the three.

I can not understand why a VEP would NOT be done because that one shows Optic Neuritis which is a condition that can sometimes move a doctor to think M.S. very quickly.

LA dx'd MS feb 2008

[shoshin]

P40 is a place where they put an electrode (I think on your head). In the SSEP, they look at the nerve signal from the stimulus (toe) through the peripheral nervous system to the base of the spine where the central nervous system starts. Then they look at the signal from the spine through the central nervous system to the end point in the brain (which seems to be where P40 is). I don't know what it means that the tech wrote down P40 and myelin. It certainly could have something to do with MS, but I don't think anyone here has the context to answer this question. The SSEP is a general sort of test that can only show an abnormality or type of abnormality; it can't show for sure that something is caused by MS, but it provide supporting evidence.

Will you see your doctor soon for the results? They probably won't mean much without talking to the doctor.

Good luck in getting some answers.

sho

[nursejenn1012]

when i had the test, the tech wrote down some numbers, after p40 and myelin, what are normal for p40??

[HVAC]

My eye part was off but I have had double vision my whole life. They sent me to a Neuro-opthamologist which for me was a big waste of time. The BAER was abnormal but I am deaf in both ears. He could not believe a Neurologist would do a BAER on me. My MS Specialist, who was not the one who did the VEP and SSEP, said he does not use them at all anymore. He thinks they are out dated something used before MRIs. My guess is they are another tool in diagnosing.

Alex

[neicy0120]

Hello, I am new to this nightmare of difficult diagnosis and also suffer with numbness and tingling in my arms, hands and legs and feet and have suffered from attacks of vertigo, weakness, and headaches for at least a decade, although the numbness and tingling is a new symptom I have had a vast array of tests done and more on the schedule, and it seems as if this is a never ending chase for an answer.
I just got out of the hospital from tons of tests//// tried to go to work the day after my release and it was so difficult to last all day...I cried the whole way home, because I was so exhausted and weak. I feel the need to take a leave of absence, which means that I am not winning this battle and it is just so frustrating...I think I just needed to vent...thanks for listening.

Neicy

[shoshin]

Bump for Lori. Quix's post is about halfway up.

[mommajuju3]

True. Too frustrating. I haven't had an MRI of the spine. I did have one of the cervical, but only one and that was with my very first MRI when this whole mess started with the facial numbness that sent me to my first neuro. They saw nothing, except they wanted to know if I had ever fractured my neck!!!!  (not that I remember!) I'm just wondering if this abnormal evoked potential is enough as is or at least enough for him to want to look at the spine. I wish I just knew how to read it so I knew whether the abnormality was coming from the peripheral or CNS. Grrrrrrrrr!!  I wish I were smart!  :-) LOL

I don't have the dry eyes/mouth, so I don't think Sjogren's is a possibility. The Devic's disease I wouldn't think would  fit because I haven't had any eye issues whatsoever. The only thing unusual about one of my eyes is that it has a sort of "birthmark" as my eye doc calls it. It is nothing more that the myelin continuing on farther into the eye than it normally does. So when you look into my eye, you see this white patch. The MS specialist had never seen it before. Not common, but not uncommon. It's nothing harmful to my vision.

I can only say that the only clear attacks that I would of had would of been the facial numbness and the vertigo attack, about 6 months apart. I had also had another attack of vertigo that happened about 4-5 years prior to all of this and the MS specialist said it was possible that this could have  been a first attack.

I'm glad you were able to get another neuro with a fresh perspective.That had to be refreshing to you!  I'm so tired, I don't know if I can handle going to another doctor after this, at least not right now. If my next appointment, which is a month away, doesn't yield some sort of result, I've just got to break from all this medical stuff. It's taking it's toll on myself and my family. I'm not moving forward with my life because of it and that's no way to live.

Leaving for vacation in 2 days!! Can't wait to spend sometime away by the beach!! I need some R&R!!

Thanks sho!! Have a great weekend and again.....Thanks a bunch!!!
Julie

[shoshin]

Yeah, it is frustrating when the doctors seem to run out of ideas. Or just want to "wait and see."

I did look at your other post. Have you had an MRI of the spine, especially the cervical spine since you have arm issues? I suppose the other thing that might help is an LP.

A couple other things they considered in my case were Sjogren's (do you have dry eye or mouth at all?) and Devic's disease or neuromyelitis optica (there's a blood test for this, but it's a little pricey).

Do you have clear attacks and remissions?

Maybe you should go to another neuro for a second opinion. Sometimes fresh eyes help. At least, they did in my case.

Sorry, I'm not of much help on these kinds of questions.

sho

[mommajuju3]

Hi sho,
Hey, thanks for the info. I am not sure what my results mean. I have tingling off and on in both my feet and hands, both sides. He was just using this as another tool, trying to rule in/out MS or other things. MRI has shown one lesion in a place that would be consistent for MS, but it has improved (I believe it's mostly if not all gone) and another frontal lobe that is quite small. Some other small foci that  is on the report that he never talks about, so I don't think he feels it's relevant or important. He feels the larger one (that is now mostly gone) was possibly viral related and the smaller frontal lobe one possibly migraine related.   My story is quite long....if you go to my profile on page two or three, of my posts, one of the posts titled "evoke potential & MRI results" dated Jul 17 (there are more than one w/ this title!!) you'll get a better idea of why he wanted this test. I think I'll just lose it if it doesn't get me any where!!!  I can't imagine being one of those here who have gone years and years without dx!!!   I'm not any where near some of them and I'm am stressed, depressed, having anxiety and insomnia!!!

Thanks for responding to me!! Have a good one!
Julie

[shoshin]

I am totally the wrong person to ask about medical reports. I have enough trouble with the stuff that is half in plain English. From what Quix said, it would seem that the no response on the scalp on the right means the signal was interrupted in the CNS and never arrived, but your report doesn't seem to state that as strongly as mine does. On the left, I think the normal latency means the speed was okay, but the not-well-formed means something still wasn't right.

What this actually *means* other than that something is wrong, I don't know. I hope you have a good doctor working on figuring this out.

There is another part in my report under "findings" which is maybe a little more similar to yours. I didn't post if before because it's mostly Greek to me, but on the off chance it's helpful, here goes:

"Right median nerve stimulation resulted in normal responses at Erb's point, N13, and N20. There was a mildly delayed N20 response with stimulation of the left median nerve. Latencies from Erb's point to N20 and N13 to N20 were increased bilaterally, worse with stimulation on the left.

"Tibial nerve stimulation resulted in absent P40 responses bilaterally. No lumbar potential was recorded with left tibial stimulation, but was present with right tibial nerve stimulation. Late responses were present. The lumbar potential with stimulation on the right was normal."

(this last bit makes it sound like the left leg/foot is worse, which is the opposite of what I would've thought although the difference is not dramatic.)

I don't know how much you can tell from an abnormal SSEP. I got the impression it's sort of non-specific for exactly what is wrong. Does your neuro have any thoughts or are you having any follow-up tests? (sorry if you've posted on this--I get everybody's stories a little confused after a while)

sho

[Sarahsmom46]

I am so glad you wrote.  I remembered reading what you said about your neurologists comments, but couldn't remember who said it.  My neuro gave me the results too and didn't make a big deal out of the very slightly abnormal findings.  So I wonder why they order these tests anyway since they are soooo painful.  

What was the VEP like?  It doesn't cause pain does it?  

-Julie

[MrsAristotle]

Hi I had the same problem when i had my SSEP done, but they did it against my wrist. I nearly passed out with pain. The operator had to call in the supervisor as she didnt know what to do with me. They did do the test but on a very low charge and unfortunately it didnt show up anything.

My VEP was positive though.

When i saw the neuro and told him what happened he said never mind the SSEP is pretty useless anyway, as it doesnt pick up the very small fibres which could be affected.

????????????? Honest injun that is what he said. Why bother i thought. I could have saved myself some pain LOL.

[mommajuju3]

Hey shoshin,

Your report seems to be quite detailed. I am wondering though what the difference in yours and mine is. The numbers (P40, N20?) are a little different and I am not sure what that means. Also one side shows a response not well formed over the cervical spine and...well here,....I'll just type it out. Can you tell me if it makes sense to you or maybe yours just makes sense cause it's so well written?

Description:

Responses were recorded over the Erb's point region, and over the spine and scalp, to stimulation of the median at the wrist on either side. With stimulation of either nerve a reproductible response was obtained over the Erb's point region. With stimulation of the left median nerve, the response over the cervical spine was not well formed, but an N20 potential was present over the scalp which had a normal latency of 19ms. With stimulation of the right median nerve, an N20 repsonse could not be clearly identified over the scalp.

Impression:

Abnormal findings bilaterally.


So, I did not have a response over the scalp on the right? Or is it possible that something was wrong with the test (not clearly identified)   (the lower limb test could not be read with "confidence" --I think it was too painful for me and it affected the test results)  But it was normal at the scalp on the left , but at the cervical spine something is not right?  
Why can't this stuff be black and white???  :-(
Thanks if you are able to offer any help. I wish my report was worded as nicely as yours!
Julie (mom2jkkl)

[Sarahsmom46]

You explained it beautifully as least to my level of understanding of such things.  When I see the results for myself I may want to bring this up again if that is ok.  Thanks.

Julie (Sarahsmom)

[Quixotic1]

Well, Shoshi, totally nailed the answer to your question.  I really don't think there is a better one.  This part of the answer is IT.

"Under the impression section, it says the results are abnormal because "the normal peripheral responses coupled with the increased central conduction time for the median responses and absent scalp (P40) responses with tibial stimulation suggest a lesion or lesions in the median and tibial somatosensory pathways from the level of the spinal cord to the cortex."

This says it technically.  Explained the Quix way, it says that the results were abnormal because they showed that the nerve signal was completely fine out in the arm and  leg (the peripheral part).  But, when they measured the part of the signal that involved the central nervous system the conduction velocity was either prolonged (in the leg) or absent.  In the arm (measuring the median nerve) the signal was fine to the spine, but never arrived at the scalp.  This means it was completely interrupted.

Both of these responses indicate that the signal ran into a area of demyelination once it left the peripheral nervous system and entered the central nervous system.  This area of demyelination either slowed the signal or completely blocked it.

And, everyone is right is saying that a positive Evoked Potentials add evidence pointing toward the diagnosis of MS, but do not diagnose it.  A negative EP tells you nothing about whether MS is present.  MS cannot be excluded because of a negative EP.

Did this make sense?  If not I will re-explain it, because that is the full answer.

Quix

[Sarahsmom46]

Thanks so much for the feedback.  It was very, very helpful.  I wish I would have had a copy of my results ahead of time so I could pin the doctor down to an explanation if I saw something wonky, but alas I wasn't that organized this time.  That test was pretty painful wasn't it?  I was in tears when they did my ankles.  

The one test they don't plan on doing with me is the VEP.  My neurologist didn't tell me why, but I think it is because I naturally have nystagmus due to a birth defect.  I guess the test wouldn't be accurate.  

Julie, when I get a copy of the results, which they said they mailed out today,  I will post them.  Maybe between us we can come up with something that would shed light on what the numbers mean.  

Sho, you had a good interpretation on your report.  I've noticed with all the testing I had done since I got sick, that good remarks are few and far between.  

Thanks again for your feedback and maybe we can all post SSEP/VEP/BAER questions to the neurology forum together and that might get one of the docs to notice.  :)

Julie (Sarahsmom)

[shoshin]

I have only had the SSEP, but my understanding is that all of the evoked potentials can be used to support an MS diagnosis when they are abnormal. They can show that something is objectively wrong with the central nervous system, but they don't say what that thing is necessarily so it could be something other than MS. On the other hand, if they're normal, that doesn't mean you don't have MS.

I posted once before about my SSEP results so I'll cut and paste from that in case it's helpful.

At the top, it says it was done for to evaluate for demyelination (which would include MS) and myelopathy (which apparently is a term "used to describe any neurological deficit related to the spinal cord itself. Most frequently, myelopathy is due to compression"--http://tinyurl.com/36lcu7).

Somatosensory evoked potential:
"SEPs are used to assess the functioning of the central and proximal portions of sensory pathways. They are obtained from pericutaneous electrical stimulation of the median nerve at the wrist or the posterior tibial nerve at the medial malleolus [ankle]. The ulnar, radial, peroneal, and other nerves can be tested. Lumbar electrodes may be used in addition to scalp electrodes for lower extremity stimulation."

Under the impression section, it says the results are abnormal because "the normal peripheral responses coupled with the increased central conduction time for the median responses and absent scalp (P40) responses with tibial stimulation suggest a lesion or lesions in the median and tibial somatosensory pathways from the level of the spinal cord to the cortex."

Anyway, what I understood when they did this test is that they measure the time it took the signal to reach from the ankle (for example) to the central nervous system (spinal cord) and then to the brain and that they could tell if the central nervous system was conducting signals slowly (which apparently mine is).

This was important to my dx because the first two neuros I saw thought I had a peripheral nervous system problem, but this showed a central nervous system problem. I still had to have MRIs, a spinal tap, and a bunch of tests to rule other stuff out, though.

sho

[sllowe]

Hi there,

Well, it's been my experience that they say the test are "good" but I'm thinking OK, means the same as good.  You'll have to get your hands on the report, and read it (that is what I did).  But, they look greek, unless they write their comments by hand.

The Drs run these test to get responses and response times on eyes to brain, muscles, etc.  I believe they run them to see if they can see something going on in the central nervous system other than what they may, or may not have uncovered during their exam.  Kind of checking your wiring and the if there is a timely response to stimulation...lol....Surely, I think men would fare better on these tests (sorry, just my sick way of trying to make myself laugh this a.m.)...

-Shelly

[mommajuju3]

Hi Julie

I'm a Julie, too!  

I had the VEP, BAER and the SSEP done at the end of May and I do have my written resutls. MY visual and hearing were normal, but he upper arms were abnormal bitlaterally. The lower legs were not able to be read "with confidence". I think this is because it was pretty much torture for me when they did the test on the ankles. I am not sure why it was so much more painful there for me, but it apparently had an affect when it came to the test results. :-(

Unfortunetly, I  haven't had any luck getting much info on what these results will mean in regards to a possible diagnosis or what I should be expecting or needing to ask at my next appointment. Quix tried to help, but EVP's really aren't here area of expertise!!  DARN!!  I have also tried posting on the neurology board, hoping that one of the doctors would respond, but my posts keep getting passed up. I guess they don't like trying to interpret EVP results???

I would love to hear what your results are when you get them!  I'll be gone on vacation next week, so if you get them that week, I won't be able to respond until after the 31st!
Good luck!
Julie