Neuro: 10:00-11:00 Scribe: Marjorie Hannon

Neuro: 10:00-11:00 Scribe: Marjorie Hannon

Thursday, January 22, 2009 Proof: Caitlin Cox

Dr. Paige Epilepsy Page 6 of 6

Note: He was running out of time so he flew through the last several slides. However, there are lecture notes on his power point, so feel free to look at those for the slides that he skipped.

I.  Introduction [S1]: Seizures and Epilepsy: Clinical Manifestations, Diagnosis, and Treatment

II.  Epilepsy clinical manifestations [S2]:

a.  [S3]: Seizure Video #1 (secondary generalized seizure)

i.  This gentleman is having what’s called a complex partial seizure; partial which spreads to become generalized. Basically it starts in one part of the brain and spreads to encompass the whole brain. You saw how it started out on the right side and now it is going to the other side. Eventually it will become symmetric. That means that the seizure spread from one side of the brain to both sides and it is manifested on the body by obtaining symmetry.

ii.  This is called a secondary generalized seizure. This is as bad as they get; this is a medical emergency. As you’ll find out, seizures can start from one place and spread in this fashion to become secondary generalized. Or they can start everywhere and start as a primary generalized seizure (video 2).

b.  Seizure Video #2 (Primary generalized seizure/ simple partial seizure)

i.  If they don’t spread, they can stay focal. You can see a little twitching on his face and arm. The nurse is with him and asks him to hold up two fingers while he is seizing. She greets him and he responds. He is following commands on one side of the body, while on the other side of the body he is seizing.

ii.  He is following commands throughout this entire event.

iii.  This is called a simple partial seizure. It is one that stays focal in one place and doesn’t spread to encompass the patient’s awareness (like in the generalized seizure).

III.  What is Epilepsy? [S4]:

a.  Epilepsy is the tendency to have seizures unprovoked.

b.  If someone has an alcohol withdrawal seizure (they drink every single day and suddenly stop) and they have a seizure, then that is not epilepsy. It is a secondary seizure, secondary to alcohol withdrawal.

c.  But if someone just starts having seizures and it is unclear why, or even if it is clear why and they have cortical dysplasia (a developmental abnormality) and we know it is a lesion but they have more than one seizure, then that is epilepsy.

d.  Epilepsy is in 1-2 % of the population so there are roughly 3 million people with epilepsy in the US.

e.  Epilepsy can arise from any place on the cortex. The cortex has different functions depending on the location. You can have seizures that manifest on the body as an abnormal implementation of the normal function of that part of the body. Examples:

i.  A seizure in the posterior or occipital region, you may have visual obscuration.

ii.  If it comes from the temporal lobe you might have memory difficulty.

iii.  Parietal lobe you might have unusual perception of your body.

iv.  Frontal lobe can give you strange psychotic-like symptoms.

v.  There is somewhat of an anatomical correlation there.

IV.  Incidence of Nonfebrile Convulsive Disorders [S5]

a.  Is high in neonates and drops down to the adult level at about five years of age.

b.  The high neonatal numbers are caused by things related to neonatal strokes, birth trauma, genetic metabolic disorders. Then you attain the normal adult rate. Then there is another climb in incidence after 65 years old because of strokes, tumors, and trauma. There is a little peak in the middle for alcoholism.

V.  Types of Seizures in Epilepsy [S6]: There are two main categories of seizures (and therefore epilepsy):

a.  Localization related (or partial or focal) seizures

i.  One category is focal epilepsy, where the seizure starts in one place, a discrete location. In some cases you can identify and actually surgically remove it to definitively cure the patient.

b.  Generalized seizures (Generalized is defined in this sense that the EEG is affected everywhere)

i.  The other category is a seizure type that seems to spring from everywhere. If we have EEG electrodes in the scalp, every single electrode is affected at once. It doesn’t start in one spot and spread, it just “boom” happens all at once. These tend to be the genetic epilepsies, and there are three main types:

1.  A generalized tonic-clonic seizure is one like the gentleman in the video, where he started out stiff and tonic and it broke down into clonic.

2.  Absence seizures are when the patient has no outward manifestation other than they just pause and stare for several seconds (10-15 seconds); these are subtle. This can happen several times a day and a patient will learn strategies for hiding them (because they are so subtle). You may see a little bit of a lip twitch. If you look at the EEG, the entire EEG is active.

3.  Myoclonic seizures (or myoclonic jerks): these are from the cortex and are just a single spike, just jerks of the whole body.

c.  EEG of generalized onset seizure [S7]

1.  If you look at someone’s EEG you see a span of normal, and then all of the sudden every single channel is affected. Some of these channels are in the front and some are in the back, but you tend to have a frontal predominance although all channels are affected to some extent.

d.  Partial seizures [S8] (focal onset)

i.  These come from one place and kind of spread like fire on the cortex. They spread through white matter channels. It is important to know that anything that is done normally can be done abnormally with a seizure (depending on where it arises). It can be motor, sensory, psychic, or even autonomic symptoms- stomach ache, piloerection, or tachycardia. We use these symptoms to try to tell where the seizure is coming from, and hopefully we can localize it so that we can remove it.

e.  EEG of Focal onset seizure [S9]: This is a cartoon representation of where the electrodes are placed.

i.  On the right side of the brain, you can see it is growing in amplitude and sharply contoured. The EEG shows the typical pattern of a seizure event: it is growing from one channel to the next and it is getting larger, higher, rhythmic amplitude.

VI.  Seizure videos #s 3, 4, 5 [S10] skipped

VII.  Localization Based on Semiology [S11]

a.  This slide illustrates what I was talking about, different localizations you can gain just by watching the patient’s seizure.

b.  One of the evaluations that we do is a video EEG which is where we try to capture a seizure with both EEG and video. The video is really critical because sometimes when a seizure starts, it is initiated from a very deep source and it may not propagate to the surface where our EEG electrodes are. Then we may be left with nothing but the “ictal” etiology (which is the term for what happens during the seizure).

c.  If we see certain motor movements, bizarre behaviors, we might think frontal.

d.  Fear, amnesia, oral automatisms, such as chewing (that the patient doesn’t realize that they are doing), we think temporal lobe.

e.  Parietal lobe is strange body morphology. For example, one patient describes having a seizure where he would look at his hand, but if he closed his eyes he felt like someone was twisting his arm. This is because the somatosensory input was scrambled by the seizure.

f.  Occipital would be some type of visual association effect.

VIII. Seizure videos #s 6, 7, 8 [S12] skipped

IX.  Seizure Classification [S13]

a.  This just kind of reiterates the two types of seizures: generalized and focal.

b.  Focal seizures are divided up into functional zones as the seizure spreads. As it begins, the patient may not be aware of what is going on even though we can see it start on the EEG. Then there is a zone where the patient notices and their hand may stiffen up unintentionally. As it spreads more, areas that allow the patient to understand what is going on (frontal lobe, parietal lobe) basically go blank. The patient becomes unaware; they can’t answer questions, they can’t understand anything.

i.  Simple partial: patient can still understand what is happening. They have a level of concern, they can make and implement a plan (example, they recognize the stiffening of their hand so they know they should sit down).

ii.  Complex partial: when it spreads to the point that they can no longer understand their environment.

iii.  Complex partial with secondary generalization: once it goes to the other hemisphere.

X.  Febrile Seizures [S14]

a.  These are generalized seizures. They happen in children 6 months (however his slide says 3 months) to 5 years. Unless they have the specific atypical features, they do not infer any additional risk of developing epilepsy as an adult. These atypical features are some that tell you that your risk has doubled from ½ to maybe 3. It is not absolute, but it just increases your risk

b.  Febrile seizures are generalized convulsions that happen in the setting of a fever.

c.  Q: does Sx stand for seizure? A: no, Sx stands for symptoms. Example: fever may be a Sx (symptom) of febrile illness.

d.  Most seizures end within 3-5 minutes. They are self-limiting. If the seizure lasts more than 5 minutes, some kind of medication is needed because it could turn into status epilepticus.

XI.  Status Epilepticus (SE) [S15]

a.  A real medical emergency because it can “cook” the person’s brain.

b.  The official definition is: either the seizure itself lasts for 30 minutes, or there are intermittent seizures without full recovery between the seizures for 30 minutes. That is the textbook definition, but if someone rolls up to the ER in the ambulance and I see that they are still seizing, then they are in status.

c.  There is a protocol that needs to be implemented with benzodiazepines, ativan, anticonvulsants, and then possibly all the way to a pharmacological coma that allows the brain to cool off and calm down. That involves intubation and going to the neural ICU.

d.  There are certain types that don’t have outward motor manifestations and those are called non-convulsive status epilepticus. Studies have been done that show that there is a high incidence of this in ICU’s of all kinds, where patients appear to be comatose but are actually seizing and no one really knows it because you can’t see it. There has been more of an effort to do EEGs on patients that are comatose.

e.  The effect on the brain is the same for both convulsive and non-convulsive: it is bad.

XII.  Lifestyle issues [S16]

a.  Epilepsy has very large social, economic, and emotional effects on patients.

b.  For the most part these patients are normal (except the fact that they have seizures).

c.  However, they can’t drive, a lot of time they can’t work, and many have reproductive issues as side effects of the anticonvulsants. Luckily it only affects 1.5 % of the population.

XIII. Epilepsy Diagnosis [S17]

a.  Etiologies of Transient Episodes [S18]

i.  One of the first questions that one has to ask when they are trying to diagnose epilepsy, or diagnose a spell (they passed out or they shook or they became unaware for a period of time), is: was it a seizure?

ii.  A number of things have to be considered when you hear of a description of a transient event or disruption in the flow of consciousness.

iii.  A stroke is one of the main things that you have to consider. Strokes can be transient in the sense that you can have a clot that gets stuck and then the anticoagulant properties of the blood dissolve it and everything is good again. You must be able to differentiate a stroke or transient ischemic attack from a seizure because you don’t want to treat a seizure with the noxious medications and you do want to treat the warning sign that you have been given that this person is at risk for a stroke.

iv.  Other considerations include migraines. Migraines are a very bizarre complex neurological disorder that can have hemiplegic manifestations (when half of your body is numb), tingling, your vision is obscured, bright lights and other manifestations that could be interpreted as a seizure.

v.  Cardiac issues are another consideration you have to keep in the back of your mind.

vi.  There are other things that are rare like movement disorders that you should be aware of.

b.  Initial Seizure workup [S19]

i.  The main focus of this slide is the fact that you really need to do an EEG and an MRI if you think the patient had a seizure. By the time the patient gets down to the ER, they have usually already had a CT, but they need an MRI because it might be a warning of a tumor, a bleed, or it may be related to a vascular malformation (a cluster of vessels could rupture and kill the person).

ii.  So a seizure a lot of the time is a sentinel event that needs to be evaluated.

iii.  SQ: What are some of the causes of seizures? A: There are a “bazillion” things that can cause seizures.

1.  There can be a genetic defect in a single channel on the cell membrane of every nerve cell in the body.