What does a normal EEG on meds mean anyways

[chmmr]

Ok so this is maybe a stupid question, but what significance does a normal EEG have for a person on meds for epilepsy?

My daughter had what appeared to be a cluster of seizures on Monday, both by my account and by what our ped witnessed (partial seizures, both complex and simple) and we gave her the emergency med (ativan) and admitted her to hospital for observation and to sleep deprive her and do an EEG the next morning.

Her EEGs have always been abnormal, both on and off meds (epileptiform abnormalities-sharp waves blah blah) but we have never had one with her on both clobazam and lamictal, and plus it was 24 hours after ativan. My pediatrician is pleased obviously that its "normal" and doesn't think the ativan is why (shes thinking the other two meds i guess). She also said that a normal eeg is just a "screen shot" in the moment and that people with epilepsy can have normal EEG's and that doesn't mean she doesn't have seizures.

So i guess i'm very confused as to what significance a normal EEG has at all?

 

[N Sperlo]

It sounds like her pediatrician thinks the medicine is doing its job.

From what I understand, without the meds your daughter has abnormal eegs, with the previous cocktail, she had abnormal eegs, and with a different cocktail, her eeg came back this time normal.
I can see why her pediatrician thinks it is a positive thing, but it is no proof that the seizures are gone.

 

[kirsten]

It means absolutely nothing except that you are not having any kind of seizure at the time of the EEG. I have had quite a few normal EEGs, but my neurologist doesn't bother too often with them because he says they will only tell him I have epilepsy, which he already knows. We only do them after a tonic clonic or when status seems to be happening. The trouble with trying to get an abnormal EEG reading is Murphy's law. When you want to see a seizure your brain pretends to be normal.

 

[N Sperlo]

In addition to what kirsten mentioned, chmmr, plenty of people here, including myself, have had a seizure of some sort during an EEG, and the EEG has come up normal.

 

[kirsten]

Interesting, Sperlo. Any idea why that happens?

 

[N Sperlo]

My neurologist said it was probably a simple partial (aura in his language) and was likely "too deep" to register. This was during a 3 day at-home EEG with nighttime video.

He was able to diagnose it due to my nocturnal behavior which he first thought was RBD, but noticed my movements matched that of epilepsy, not RBD. According to the EEG, I was awake, though. I have no memory of any of it happening.

 

[kirsten]

I had no idea they were doing at home EEGs. That's good news.

 

[chmmr]

It sounds like her pediatrician thinks the medicine is doing its job.

From what I understand, without the meds your daughter has abnormal eegs, with the previous cocktail, she had abnormal eegs, and with a different cocktail, her eeg came back this time normal.
I can see why her pediatrician thinks it is a positive thing, but it is no proof that the seizures are gone.

Basically yes. But i guess i'm confused as to how after she had a cluster of seizures the day before that she could have a normal EEG.

 

[kirsten]

The medication is more than likely keeping the seizures isolated so that there isn't any epileptic activity in between. That's a positive sign, although you will obviously work towards a more complete result.

 

[N Sperlo]

The mind is a mysterious thing....

I'm as clueless as you.

 

[pccoder]

I had no idea they were doing at home EEGs. That's good news.

They're called "Ambulatory EEGs". I had one back in November, the first 3 days before Thanksgiving. I stayed home from work that whole week. Those 3 days all my partials stopped, then immediately started back up after I was off the EEG. I think the brain is saying, "ha ha, you can't figure me out!"

 

[N Sperlo]

They're called "Ambulatory EEGs". I had one back in November, the first 3 days before Thanksgiving. I stayed home from work that whole week. Those 3 days all my partials stopped, then immediately started back up after I was off the EEG. I think the brain is saying, "ha ha, you can't figure me out!"

Yea. That IS what that hospital bill said... :roflmao:

 

[horsehead]

I have had four seizures during eegs docs say they are non epileptic because they didn't show anything. and people on here have said they may just be to deep in the brain. i dont know.

 

[N Sperlo]

Since you have had more than one, horsehead, and I'm assuming they don't know why you have them, my best guess is that the docs are full of crap.

 

[horsehead]

They are definately full of crap n sperlo I've had seizures since i was 10. due to one video eeg the docs decided my seizures were non epileptic and took me off all meds. I had to go through almost daily seizures and wait about 3 years before i could get on meds again

 

[lucycherish]

I have questioned this with my neurologist, I have had numerous EEG's and scans which all came back normal, one was a week after a Grand Mal, another was during and not long after absences or myoclonic jerks, he basically said the smaller seizures are harder to detect and it meant that no damage was being shown on the scans, I did have one slightly odd patch after the grand mal but all healed :/ it baffles me still though, hope your little one is ok x

 

[Nakamova]

Some kinds of epilepsy produce characteristic abnormal brainwaves interictally -- i.e., even when you're not having a seizure. They aren't the same kinds of patterns that show up during a seizure, but they're still considered to be indicative of epilepsy. That's the case for me. So if the EEG comes up normal, that means the meds are definitely doing their job. I had an EEG last fall to see if there was a chance I could consider coming off meds -- but it was abnormal, which tells me that A. My brain is still unhealthy, and B. I'm right on the edge in terms of my dosing. I could probably benefit from a slightly higher dose, but I'm not going there yet.

Other kinds of seizures might not show up on an EEG because they are too brief, or they originate too deep in the brain to show up, and they may not have a characteristic interictal pattern. That doesn't rule out epilepsy. The EEG isn't perfect -- it can generate false positives and false negatives -- so the best neurologists will make a diagnosis based on the actual symptoms rather than on the EEG results alone.