Epilepsy Talk

EEGs and Beyond — Which Tests Do You Need? | June 4, 2021

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.

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Resources:

https://www.webmd.com/epilepsy/guide/diagnosing-epilepsy#1

https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=85&contentid=P00811


20 Comments »

  1. Thank you! This information is so helpful!

    Liked by 1 person

    Comment by Nancy — June 4, 2021 @ 9:24 AM

  2. Glad I could be of help to you!

    Like

    Comment by Phylis Feiner Johnson — June 4, 2021 @ 9:25 AM

  3. Reblogged this on Disablities & Mental Health Issues.

    Like

    Comment by Kenneth — June 4, 2021 @ 9:35 AM

  4. Yes, a “normal” EEG. The patient is inventing the symptoms. The patient is a whiner and a seeker after attention and a waster of the doctor’s valuable time.

    My temporal lobe dysrhythmia is best imaged by an fMRI, but my then internist knew better. What you need is Paxil, she said. As we now know, Paxil for me is poison.

    Thank you for this valuable intro to the relevant technologies.

    Liked by 2 people

    Comment by HoDo — June 4, 2021 @ 10:42 AM

    • You are 100000% right. I’m going through this right now myself. Antidepressants are their answer to everything to get you to shut up.

      Liked by 1 person

      Comment by Hetty Eliot — June 5, 2021 @ 9:12 AM

      • It just occurred to me that when the statistics say more women are depressed than men, whether the facts are that more women are medicated for depression. There was an article in The NY Times not long ago about a woman who was being “treated” – and it rarely is a treat – for depression when she actually had a serious neurological problem. As in, oh, you’re female, you must be depressed.

        Liked by 2 people

        Comment by HoDo — June 5, 2021 @ 9:24 AM

      • Exactly. For years I thought my seizures were panic attacks, so they gave me SSRI’s, because it’s normal during a panic attack to lose your sight and hearing when you feel your body liquifying as your stomach flies up into your head etc etc etc……..

        It’s funny, when I read your comment, I had just discovered the carton of milk on top of the refrigerator where I put it yesterday when I was spacing out, obviously bc of my mood.

        Liked by 1 person

        Comment by Hetty Eliot — June 5, 2021 @ 5:23 PM

      • Some of the seizures I had in my early 30s were so horrendous that a panic attack would have been a reasonable reaction. I wonder if they might occur in tandem?

        Liked by 2 people

        Comment by HoDo — June 5, 2021 @ 6:42 PM

      • My neurologist thinks they can overlap.

        Liked by 1 person

        Comment by Hetty Eliot — June 8, 2021 @ 8:43 PM

    • Now that I think of it, my psychiatrist who is also a neurologist once told me that sometimes, when the temporal lobe is involved, a seizure can also set off emotions, so that I might be depressed, not In response to seizing, but as a integral part of the seizing.

      Liked by 1 person

      Comment by HoDo — June 5, 2021 @ 8:44 PM

  5. Keep on pushing those drugs, doc. And how much are you getting paid to do so?

    Like

    Comment by Phylis Feiner Johnson — June 4, 2021 @ 10:55 AM

  6. I remember my last eeg. I was approaching five years since surgery. I had one six months after surgery that they said showed no activity. I wanted so bad to reach five years seizure-free that I feel I got myself worked up and started getting feelings I didn’t like. I asked for another eeg to make sure there was no activity and even though they felt I didn’t need it, they agreed to give me one to put me at ease.

    For you people who have had epilepsy for 50 years or more, remember getting a dozen needles stuck in your head for the eeg?

    The WADA test was an adventure, too. You’re wearing just a gown and it’s freezing in that room! I call it wierd and frustrating. You get shots through your groin to deaden one side of your brain then the other. The wierd part is looking at a simple picture and you can’t even say what it is. For me, the frusatrating part was when they asked me to count to 25 and I couldn’t even get to three. But for me, this is how they found out the side they were doing my surgery on had control of my math and went around it.

    Needless to say, I support every test they give us.

    Liked by 1 person

    Comment by Ed Lugge — June 4, 2021 @ 12:49 PM

  7. The WADA test sounds like modern “torture”!

    Thank goodness you didn’t lose your math talents.

    Like

    Comment by Phylis Feiner Johnson — June 4, 2021 @ 1:58 PM

  8. “Good news! You’re fine! iT’s YoUr MoOoOoOod!!”

    Liked by 1 person

    Comment by Hetty Eliot — June 4, 2021 @ 10:31 PM

  9. Don’t forget the SEEG. It was through this test that it was determined that I could not have surgery on my left temporal lobe after already having had a resection on the right. I don’t know if this test is used for initial diagnosis though.

    Liked by 1 person

    Comment by Donna Jones — June 5, 2021 @ 4:11 PM

  10. Well, whether it is or not, that was an important omission.

    Actually, Stereoelectroencephalography (SEEG) is “a minimally invasive surgical procedure that is used to precisely find the areas of the brain where seizures originate. SEEG covers more area than a conventional EEG.” https://my.clevelandclinic.org/health/diagnostics/17457-seeg-test#results-and-follow-up

    So, thanks for pointing that out, Donna.

    Like

    Comment by Phylis Feiner Johnson — June 5, 2021 @ 5:07 PM

  11. One day at work i had what i thought was a faint spell. That day i went to the ER to get checked out. Well i was there for like 3 hrs before someone decided to do a CT scan. Problem found, nurse came into my room and told me the results, a brain tumor the size of a baseball. I could not believe it i thought i was going to die, so i asked her if she could bring me a printout she did and i was awe struck.

    Liked by 1 person

    Comment by Zolt — June 6, 2021 @ 8:15 AM

  12. Zolt, that was certainly a harsh way to find out. But at least they finally gave you the appropriate test.

    How many tests did you go through first?

    Like

    Comment by Phylis Feiner Johnson — June 6, 2021 @ 9:27 AM

  13. Not sure what all the test they did, since back than i didn’t know much about what hospitals do. I know they did blood test and they thought i may have some lung issue, since i smoked, but lungs checked out fine. I was there from 4pm till 9:30 when they told me what they found. I watched the ER room go from 50 people down to one or 2. one being me.

    Liked by 1 person

    Comment by Zolt — June 6, 2021 @ 3:08 PM

  14. Scary.

    Like

    Comment by Phylis Feiner Johnson — June 6, 2021 @ 5:29 PM


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    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.

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