Epilepsy Talk

Beyond EEGs — Diagnostic Tools for Epilepsy | February 23, 2017

How many of us have heard: “Your EEG is normal. You’re fine..”(“It’s all in your head?”)

I know of people who have had 5 EEGs, only to be properly diagnosed when they finally had Video EEG Monitoring. 

So if someone is trying to pass you off or is ignoring your symptoms, perhaps you should become a little more familiar with your diagnostic options…

EEG (Electroencephalogram) — is a non-invasive test which detects and records electrical impulses on the surface of the brain.

These impulses are transmitted from small metal discs, placed on the person’s scalp, through wires which are connected to an electroencephalograph.

This instrument is used to register the activity and record it on graph paper or on a computer screen. It is a safe and painless procedure which will not affect you in any way.

An EEG is used by a neurologist to determine whether there are any irregular electrical activities occurring in the brain which may produce seizures.

It can help identify the location, severity, and type of seizure disorder.

An abnormal EEG does not diagnose epilepsy nor does a normal EEG reading exclude it.

Video EEG Monitoring — allows prolonged simultaneous recording of the patient’s behavior and the EEG.

Seeing EEG and video data at the same time, permits precise correlation between seizure activity in the brain and the patient’s behavior during seizures.

Video-EEG can be vital in the diagnosis of epilepsy and epileptic seizures.

It allows the doctor to determine:Whether events with unusual features are epileptic seizures, the type of epileptic seizure, and the region of the brain from which the seizures arise.

Continuous Video EEG Monitoring – studies the brain waves over time.

This can be accomplished through continuous Video EEG Monitoring, where a patient stays in a special unit for at least 24 hours.

Antiepileptic medication is stopped for the duration of this test, since the objective is for seizures to occur so the abnormal brain waves they produce can be recorded.

A video camera connected to the EEG provides constant monitoring, enabling the medical team to pinpoint the area where a seizure occurs and track the patient’s physiological response to the seizure.

Continuous monitoring can also help distinguish between epilepsy and other conditions.

It can characterize the seizure type for more precise medication adjustments and locate the originating area of seizures within the brain.

AEEG (Ambulatory Electroencephalography) — is a relatively recent technology that allows a prolonged EEG recording in the home setting.

Its ability to record continuously for up to 72 hours increases the recording of an ictal event or interictal discharges.

An AEEG is a less expensive alternative to in-patient monitoring, with costs that are 51-65 percent lower than a 24 hour inpatient admission for Video-EEG monitoring.

CAT Scan (Computerized Axial Tomography) or CT (Computed Tomography) – is an imaging technique that is a safe and non-invasive, using low radiation X-rays to create a computer-generated, three-dimensional image of the brain.

It provides detailed information about the structure of the brain by using a series of X-ray beams passing through the head to create cross-sectional images of the brain.

These may reveal abnormalities (blood clots, cysts, tumors, scar tissue, etc.) in the skull or brain which may be related to seizures.

It allows physicians to examine the brain, section by section, as the test is being conducted.

The CAT scan helps to point to where a person’s seizures originate.

MRI (Magnetic Resonance Imaging) – is a safe and non-invasive scanning technique that uses a magnetic field, radio waves and a computer to produce two or three-dimensional images of the brain.

This detailed picture of brain structures helps physicians locate possible causes of seizures and identify areas that may generate seizures.

No X-rays or radioactive materials are used, therefore this procedure is not known to be harmful.

An MRI offers doctors the best chance of finding the source of seizures.

Because seizures can arise from scar tissue in the brain, an MRI can show scar tissue and allow doctors to determine the nature of it.

The images produced from the MRI are extremely precise.

The information provided by MRI is valuable in the diagnosis and treatment of individuals with epilepsy and in determining whether surgery would be beneficial.

Functional MRI  takes images in “real-time” sequence and faster than the traditional MRI.

By providing information about active brain tissue function and blood delivery, it is more precise and is often used before surgery to create a map of the brain and indicate where language, motor and sensory areas are located.

During the scan, the patient is asked to perform certain tasks, such as tapping fingers or repeating a list of words.

From the image, the neurological team can locate the exact seizure area of the brain.

MEG (Magnetoencephalography) – this technique has been available for several decades, but it is only recently that scanners involving the whole head have been available.

The brain scan is based on natural magnetic fields.

Detectors are placed on the skin near the head and then magnetic waves are used to measure brain activity.

MEG is most often used to find the precise point in the brain where the seizures start by detecting the magnetic signals generated by neurons.

With these signals, doctors can monitor brain activity at different points in the brain over time, revealing different brain functions.

While MEG is similar in concept to EEG, it does not require electrodes and it can detect signals from deeper in the brain than an EEG.

Doctors also are experimenting with brain scans called:

MRS (Magnetic Resonance Spectroscopy) — that can detect abnormalities in the brain’s biochemical processes, and with Infrared Spectroscopy, a technique that can detect oxygen levels in brain tissue.

PET (Positron Emission Tomography) — a scanning technique which detects chemical and physiological changes related to metabolism.

It produces 3-dimensional images of blood flow, chemical reactions and muscular activity in the body as they occur.

And it measures the metabolism of glucose, oxygen or other substances in the brain, allowing the neurologist to study brain functions.

By measuring areas of blood flow and metabolism, the PET scan is used to locate the site from which a seizure originates.

A small amount of radioactive substance is injected into the body. When this substance reaches the brain, a computer uses the recorded signals to create images of specific brain functions.

This functional image of brain activity is important because these changes are often present before structural changes occur in tissues.

The information provided by the PET scan is valuable in both the diagnosis of seizure type and the evaluation of a potential candidate for surgery.

PET images are capable of detecting pathological changes long before they would be made evident by other scanning techniques.

SPECT (Single Photon Emission Computed Tomography) — primarily used to view how blood flows through arteries and veins in the brain.

Tests have shown that it might be more sensitive to brain injury than either MRI or CT scanning because it can detect reduced blood flow to injured sites.

The test can track cerebral blood flow and detect alterations in brain metabolism between and during seizures. SPECT scanning is also useful for presurgical evaluation of medically uncontrolled seizures.

The Wada Test (Intracateroid Sodium Ambobarbital Test)helps to identify the areas of a person’s brain that control speech and memory functions.

During this pre-operative procedure, an angiogram of the brain is taken (an X-ray of the brain’s blood vessels).

A drug is then injected into the patient that anesthetizes one side of the brain.

The patient is asked to respond to a series of memory and speech-related tests.

From this test, the neurosurgical team can determine where the areas of the brain that control speech and memory are located, and avoid those areas during surgery.

Blood Tests – often blood samples are taken for testing, particularly when a child is involved.

These blood samples are screened for metabolic or genetic disorders that may be associated with the seizures.

They also may be used to check for underlying problems such as infections, lead poisoning, anemia, and diabetes that may be causing or triggering the seizures.

 

To subscribe to Epilepsytalk.com and get the latest articles by email, simply go to the bottom box of the right column and click on “Follow.”

Resources:

http://www.webmd.com/epilepsy/guide/epilespy-diagnosis-tests

http://www.mayoclinic.org/diseases-conditions/epilepsy/diagnosis-treatment/diagnosis/dxc-20117234 

http://www.hopkinsmedicine.org/neurology_neurosurgery/centers_clinics/epilepsy/diagnosis/

https://www.epilepsysociety.org.uk/tests-epilepsy#.WAe0OuArLtU

http://www.rch.org.au/neurology/patient_information/about_epilepsy/#Diagnostic_tests

 


37 Comments »

  1. I really enjoyed your post! I have been diagnosed with Juvenile Myoclonic Epilepsy and have had many EEG’s done, some came back normal and other’s have shown seizure activity. I’ve had other test’s done also, but the EEG seems to be the most popular, in my case anyway! Great Article!

    Like

    Comment by C.Gilpin — February 23, 2017 @ 3:14 PM

  2. Thanks for the compliment.

    Glad it worked for you.

    Like

    Comment by Phylis Feiner Johnson — February 23, 2017 @ 3:26 PM

  3. What if the video EEG records “epileptiform discharges,” but not an actual seizure? Also, are the terms, “epilepsy” and “seizure disorder” used interchangeably?

    Like

    Comment by Martha — February 23, 2017 @ 4:22 PM

  4. I’m scheduled for a video eeg and im scared.
    Had seizures since I was 18 months.

    Like

    Comment by Bonnie — February 23, 2017 @ 5:18 PM

    • Hi Bonnie, Is this your first Video EEG in all that time?

      Do you know how long it’s going to last?

      For those people having the 24-72 hour Continuous Video EEG , all they complain of is BOREDOM! 🙂

      So, bring a laptop or book or whatever you find passes the time, along with you.

      Like

      Comment by Phylis Feiner Johnson — February 23, 2017 @ 5:35 PM

      • There is nothing to be afraid of Bonnie I know I am in the same position I have had hereditary epilepsy since I was 18 months old and just turned 49 yesterday. They have ran every test known to man on me and still can’t explain it.

        Like

        Comment by Jeanine Bunt — February 23, 2017 @ 10:59 PM

      • When I was ages 14 and 21 I has in patent 72 hour eegs they were horrible. They cut my melds way back and just watched me seize. I don’t know what they plan on getting from this.

        Like

        Comment by Bonnie — February 24, 2017 @ 4:30 PM

  5. After more than 56 years, my neurologist I have today suggested last week to have a HEART monitor hooked on me for 30 days, to signify what the heart activity is doing which may cause me to have a GRAND MAL or other seizure activity that will lead into a GRAND MAL seizure. I can clearly see how any severe brain activity can effect the heart, but the heart causing a seizure or other seizure activity, that is a switch. Any help on this issue would help, as I know food chemicals WILL effect both heart & brain health 24/7 when all the MSG’s & ASPARTAME’s are daily saturated by the mouth & into the blood stream. They all know that too, but say nothing about it.

    Like

    Comment by C D — February 23, 2017 @ 6:03 PM

    • C D, sometimes the aftermath of an “overexcited” heart will lead to a seizure. (I know, it’s usually the other way around.)

      But people have strokes and then seizures and vice versa.

      I wore a heart monitor for 2 weeks, to be sure my heart wasn’t the cause of my seizures.

      Go figure.

      Like

      Comment by Phylis Feiner Johnson — February 23, 2017 @ 8:31 PM

      • Wow now that’s wild !
        I’m going to bring this up to my doc.

        Like

        Comment by Bonnie — February 24, 2017 @ 4:34 PM

  6. After my first seizure 3-1/2 years ago I had a point in time 30+minute EEG. I was diagnosed with bilateral TLE . At my request about 2 years ago I asked for a 5-day video EEG. That revealed no seizure activity. Does that happen sometimes? Is this an outlier? I have continued to have focal seizures with and with out loss of awareness, tonics characterized by falling like a felled red wood tree. Most of my seizure activity happens every 4-6 weeks; some at night, some in the day time.

    I’d appreciate your input.

    Like

    Comment by Susan Reed — February 23, 2017 @ 6:10 PM

    • Yes Susan, people have had Continuous Video EEG Monitoring with no seizure activity showing.

      Sometimes they do it repeatedly until the seizure shows itself.

      Is your neuro concerned?

      If so, you might want to go the MRI route.

      Like

      Comment by Phylis Feiner Johnson — February 23, 2017 @ 8:25 PM

  7. I realize some neurologists take people off meds to do the video EEG, but why? If you were on a drug schedule and trouble popped up anyway, why spoil the baseline? I have done a few of those 48 hr sessions. I asked whether I should take the drugs. The answer was yes, take them – we already know what your brain does without them.

    Like

    Comment by Kate Jacques — February 23, 2017 @ 8:44 PM

    • Good question, Kate.

      I guess they think they’ll have a better chance of exasperating a seizure. You know, sort of like “bring it on!”

      Like

      Comment by Phylis Feiner Johnson — February 23, 2017 @ 9:13 PM

  8. When they didn,t give all all med,s at 9;00 am and 9;00 pm. They wanted me to seizure, to get a better idea of what,s going on. They said what I had was not a seizure, I guess I out grew them. But I will alway,s have epilepsy untill the day I die,

    Like

    Comment by Michele Metzger — February 23, 2017 @ 9:49 PM

  9. Just turned 49 yesterday and have had hereditary epilepsy since I was 18 months old and they have ran every one of those tests on me and more and still can’t explain it.

    Like

    Comment by Jeanine Bunt — February 23, 2017 @ 11:02 PM

    • Sigh. Jeanine, so many people are in the same predicament. Maybe that’s why they call them “tests”??? 😦

      Like

      Comment by Phylis Feiner Johnson — February 23, 2017 @ 11:11 PM

  10. Following; thank you for this article. I just recently had a normal EEG and I had hoped that meant I didn’t have epilepsy.

    Like

    Comment by Angela — February 24, 2017 @ 1:20 AM

    • Hi Angela. Normal is good when your seizures are under control and all is OK.

      Its when seizures AREN’T under control and people keep on getting “normal” readings that they worry.

      Like

      Comment by Phylis Feiner Johnson — February 24, 2017 @ 9:47 AM

      • Thank you — I see the neurologist Tuesday so I will be asking. I am wondering if nocturnal seizures would show up on a day time EEG.

        Like

        Comment by Angela — February 24, 2017 @ 9:23 PM

  11. Well Bonnie, I guess they were just trying to verify your seizures and where they came from. (Duh.)

    And hopefully to see if they were on the right track with your meds. (Were they?)

    Like

    Comment by Phylis Feiner Johnson — February 24, 2017 @ 5:19 PM

    • they said they come from the right frontal lobe and that’s what it showed, and my doc was on track with my meds. March 1st is my next inpatient, my grandson told me to be brave.

      Like

      Comment by Bonnie — February 24, 2017 @ 7:03 PM

  12. Angela, “It can be tricky to diagnose nocturnal seizures because of when they occur,” — that’s all I was able to find in my research. 😦

    Like

    Comment by Phylis Feiner Johnson — February 25, 2017 @ 11:01 AM

    • Thank you so much — I really appreciate it. I think it is unlikely the neurologist will be able to say yes or no either.

      Like

      Comment by Angela — February 25, 2017 @ 8:55 PM

  13. I learn a lot from here.

    Like

    Comment by Michele Metzger — February 25, 2017 @ 9:26 PM

  14. hi everyone me i got my first seizure on the 03 of february 2017 ..the doctors ar still not sure what could be the course because they only happen on my sleep js this once i got them when i js woke up from bed i fell an i broke my front teeth….

    i wish to knw how offen do you get ur seizure
    me its an every week thing an am not on medication cos doctors said its not epilepsy its nightmares ….

    Like

    Comment by zethu — March 1, 2017 @ 4:23 PM

    • Studies have shown that 10 – 45% of people with epilepsy have seizures that occur predominantly or exclusively during sleep or occur with sleep deprivation.

      Interruption in REM (Rapid Eye Movement), is the culprit.

      Because sleep terrors occur in slow waves — the first step of sleep and the last third – cause those night terrors.

      Nocturnal seizures are not likely to occur in the middle of the night. They usually appear shortly after you’ve fallen asleep or just before waking up.

      Some people have seizures occur only during sleep while others have both daytime and nocturnal seizures.

      As you can guess, regular sleep habits are important, especially for those with sleep related seizures.

      Seizures may be triggered by missing sleep or sometimes even by getting too much sleep.

      But if you’re worried that you might have a seizure during the night, it can be all that more difficult to sleep.

      I know that my instinct was trying stay awake to keep those horrible experiences at bay. (I used to try to tear out my hair.)

      But if you’re afraid of going to sleep, then the whole cycle begins again.

      Because insufficient sleep can lead to increased seizure activity, making the problem worse.

      Sometimes the tendency toward seizures in sleep may be reduced by increasing the evening dosage of anticonvulsant medication.

      If the seizures occur with falling asleep in the early evening, the supper dosage may be increased.

      If they tend to occur in the early morning around the time of awakening, the approach may be to increase the bedtime dosage of medication or to use a longer acting anticonvulsant or a time release capsule.

      (I’m a fan of longer acting meds because they make me feel more secure. But, that’s only me.)

      Have you had an EEG to determine the cause?

      Have you had a sleep study?

      Because, often sleep studies (Polysomnography) with expanded EEG aids can indicate the difference between seizures and parasomnias.

      (Parasomnias are a category of sleep disorders that involve abnormal movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping, between sleep stages, or during arousal from sleep.)

      Like

      Comment by Phylis Feiner Johnson — March 1, 2017 @ 6:09 PM

  15. Is anyone here familiar with cataplexy? Before being diagnosed with seizure disorder (partial complex seizure) I suffered with this for many years.

    Like

    Comment by Natalie — March 17, 2017 @ 7:32 PM

    • Cataplexy is a sudden and uncontrollable muscle weakness or paralysis that comes on during the day and is often triggered by a strong emotion, such as excitement or laughter.

      Without much warning, the person loses muscle tone and can have a slack jaw, broken speech, buckled knees or total weakness in their face, arms, legs, and trunk.

      A person experiencing total cataplexy stays awake and is aware of what is happening, but cannot move.

      These episodes last up to a minute or two, and some people may fall asleep afterwards.

      The frequency of cataplexy episodes varies widely among people with narcolepsy.

      Some individuals avoid emotions that may bring on cataplexy.

      The loss of muscle tone in cataplexy occurs because of the inability to regulate sleep and awake states — meaning that elements of each can overlap.

      During normal rapid eye movement (REM) sleep, there is a natural loss of muscle tone.

      In the case of cataplexy, that characteristic of REM sleep occurs suddenly during the day, causing weakness or full paralysis, even as the person remains awake during the episode.

      https://sleepfoundation.org/narcolepsy/content/cataplexy

      Like

      Comment by Phylis Feiner Johnson — March 17, 2017 @ 7:55 PM

  16. Hello Phylis. My adult son David began tonic clonic seizures as an infant. Many EEG tests and several MRI’s continually confirm this diagnosis. There also is some damage in his left temporal lobe from use of internal forceps at birth–showing up on all tests. Trileptal controls the tonic-clonic seizures. But it’s his confusion, forgetfulness, even some fear associated with ‘zoning out’ that continues to be a problem– the zoning out associated with partial complex or focal seizures (so many names)– has dogged him & got him fired from his last attempt to work in bulk food department of a local food co-op. Today he is 55 and has been receiving Social Security disability for a few years based on his blanking out. Last visit with his neurologist the doc hypothesize that perhaps David’s ‘zoning out’ is a conversion disorder. He suggested that son see a neuropsychologist. We’d have to help him travel 4 hrs to get to a qualified person and then what? If that unknown person decides, “oh yeah, this is PNES” won’t that threaten son’s standing with SSDI (Social Security Disability Insurance) since he was ‘awarded’ SSDI based on plain old, everyday seizures (I repeat, his irregular brain activity always shows up on any/all EEG and/or MRI as does the messed up temporal lobe area). Nothing changes the way his brain works & doesn’t work– he’s also diagnosed with learning disabilities, PTSD, anxiety, and ADD. Although having multiple challenges, the SSDI lawyer said it would be the seizure disorder which which would win his case with SSDI (and it did). What husband & I fear is that if he gets the testing done and someone decides his daytime problems are due to PNES, then won’t he lose SSDI? Or, at least, I will have to start all over again trying to get him back on the SSDI rolls under one of his other diagnoses? Without SSDI/with Medicare coverage, David will be back out on the streets or we all will.

    Liked by 1 person

    Comment by 3 Redwoods — March 27, 2017 @ 8:42 PM

    • I think in light of other conditions, he would not be denied. But I’m no expert.

      If push comes to shove, I would either contact your local Epilepsy Foundation office for help or hire a professional disability lawyer.

      Like

      Comment by Phylis Feiner Johnson — April 8, 2017 @ 2:53 PM

  17. I think you should look into the neuropsychologist. It’s not just a matter of PNES, it’s a matter of a full cognitive assessment and then, possible cognitive therapy.

    I know this therapy has helped many regain “lost” executive skills and I would suggest you look into it.

    This article may be of interest to you, Redwoods:

    Exactly what IS Neuropsychology?

    https://epilepsytalk.com/2017/02/10/exactly-what-is-neuropsychology/

    Like

    Comment by Phylis Feiner Johnson — March 28, 2017 @ 10:12 AM


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

    About the author

    Phylis Feiner Johnson

    Phylis Feiner Johnson

    I've been a professional copywriter for over 35 years. I also had epilepsy for decades. My mission is advocacy; to increase education, awareness and funding for epilepsy research. Together, we can make a huge difference. If not changing the world, at least helping each other, with wisdom, compassion and sharing.

    View Full Profile →

    Enter your email address to follow this blog and receive notifications of new posts by email.

    Join 2,346 other followers

    Follow Epilepsy Talk on WordPress.com
%d bloggers like this: