EEG201 Midterm (Combine with Quiz 1)

What is the proper order for applying Personal Protective Equipment (PPE)?

1. Wash Hands 2. Gown 3. Mask 4. Goggles 5. Gloves

What percentage of people with epilepsy die from SUDEP?

15 - 20%

What are the microvolts (µV) for ECS recording?

2.0 µV

What is the duration of a spike?

20 to under 70 miliseconds

Positional Plagiocephaly

Asymmetrical head from repeated pressure to the same area of the head, as in having the same sleeping position.

What arrhythmia has the risk of thrombus?

Atrial fibrillation

Why is the QRS complex larger than the P wave in an EKG?

Because the ventricles contain more muscle mass than the atria

Interictal

Beginning with no seizure activity

Hydrocephalus

Build-up of CSF causing increased pressure in the head, enlarged ventricles and in children abnormal skull shape.

Fetal Alacohol Syndrome

Caused by consumption of alcohol during pregnancy.

Anencephaly

Cephalic disorder that results from a neural tube defect that results in major loss of brain development.

If a choice must be made between equal spacing of electrode pairs or anatomy:

Choose anatomy

Time since birth (legal age) is called?

Chronological Age

Age in weeks since the moment of conception. Gestational age + Chronological age is called?

Conceptional Age

Simple Partial Seizure

Does not have a period of impaired consciousness

Postictal

An ending, or after the seizure has ended-

Plagiocephaly

Fusion of either the right or left side of the coronal suture.

What type of epilepsy is the most dangerous?

Generalized Tonic Clonic Status Epileticus

Time of growth in the uterus calculated from the first day of the Mother's last menstrual period is called?

Gestational Age

What type of tumor spreads in a finger like fashion and removal is virtually impossible?

Glial

If all impedances are "red" or high, what should you check first?

Ground

Complex Partial Seizure

Has a period of impaired consciousness

Circumferential

Hatband electrode derivation.

Microcephaly

Head circumference measurement greater than three standard deviations (SD) below the population mean for age and sex.

Frequency is measured in what?

Hertz (Hz)

The HFF and the LFF are measured in?

Hertz (Hz)

Seizure types can be determined by?

How and where they begin in the brain.

________________ is a disease caused by a faulty gene.

Huntington's disease

MRI

Preferred imaging test for hydrocephalus.

Craniosynostosis

Premature closure of the cranial sutures.

What is morphology?

Relating to the structure/form of an EEG wave

Vascular dementia is the ______ most common cause of denentia after Alzheimer's disease.

Second

Treatments for Hydrocephalus

Shunt and ETV

This arrhythmia fluctuates with inhaling/exhaling and is common in children.

Sinus arrhythmia

Ventricular arrhythmias are the mechanism of the majority of cases of?

Sudden Death

Describe Delta waves.

● .5 - 3 HZ ● Slow/High Amplitude ● Generalized ● Seen in Sleep

Describe Theta waves.

● 4 - 7 Hz ● Slow ● temporal/generalized ● Seen in drowsy/sleep

Describe Alpha waves.

● 8-13 HZ ● Sinusoidal ● Located in Occipital Region ● Seen in Wake

Describe Beta waves.

● >13 Hz ● Fast/Low Amplitude ● Located in Frontal Region ● Seen in Wake

Types of Generalized Seizures

● Absense ● Generalized Tonic Clonic ● Myoclonic ● Tonic ● Clonic

Adult Onset

Normal pressure hydrocephalus, can mimic dementia.

Quiet Sleep

No eye or body movement, regular respirations, Tracé Discontinu (TD).

If you patient is sweating what can you do to try to minimize it?

-Use alcohol to wipe face and head -Hyperventilate the patient for 3 minutes -Place a fan in the room

Lambda waves may be seen?

1 - 2 Years of Age

Most cortical activity that is of the clinical interest falls in the range of about?

1 - 30 Hz

What is the proper order to remove Personal Protective Equipment (PPE)?

1. Gloves 2. Wash Hands 3. Goggles 4. Gown 5. Mask 6. Wash Hands

Tracé Discontinu is replaced by Tracé Alternant at approximately what age?

34-37 Weeks Conceptional Age

Full Term is defined as?

38 - 40 weeks gestational age.

What is the duration of a typical Absense seizure?

4 - 10 seconds

"Time constant" refers to the time it takes for the calibration signal to degrade by what percentage of its total amplitude?

63%

What is the duration of a sharp wave?

70-200 miliseconds

Scalp impedances should be?

<10KΩ

REM/Active Sleep

Irregular respirations and increased body movement.

Ictal

Major signs and symptoms of a seizure

Seizures might cause the vital centers in the brainstem that control blood pressure and respiration to?

Malfunction

Amplitude is measured in what?

Microvolts (µV)

What is the duration of a waveform measured in?

Miliseconds

Referential Montage

Montage used to best define greatest amplitude of abnormalities. Method of localization = area of greatest amplitude

Bipolar Montage

Montage used to best determine focus or localization of abnormalities. Area of localization = phase reversal

Double Banana

Most common montage, electrodes record from temporal and parasagittal areas of the head from anterior to posterior electrode sites.

A surface negative wicket-type 7-11 Hz rhythm found in the central head region is known as?

Mu Rhythm

Is FIRDA associated with EEG epileptiform activity and tumors?

No

Hypnagogic hypersynchrony

The occurrence is abrupt and it can either be intermittent or continuous for several minutes.

Morphology refers to?

The shape of a waveform.

How many types of filters are there for EEG recording purposes?

Three

Generalized, focal, and unilateral all describe?

Topographic Origin

Discontinuous pattern characterized by bursts of frequencies with low voltage activity usually lasting 1-4 seconds between bursts are?

Tracé Alteranant

_______________________ is a chaotic rhythm originating in the ventricles, resulting in no cardiac output.

Ventricular fibrillation

What does the T wave represent in an EKG?

Ventricular repolarization

_______________________ is defined as three or more consecutive PVC's.

Ventricular tachycardia

Lambdoids

● Also called positive occipital sharp transients of sleep (POSTS) have a checkmark (biphasic) morphology with initial surface positivity and often appear in trains up to 4 to 5 Hz ● POSTS are usually synchronous but can be asymmetric in size. ● They are most commonly seen between 15 and 35 yr of age, and usually in light sleep. ● They may appear before the alpha rhythm completely evaporates in drowsiness. ● POSTS are a commonly encountered variant pattern on routine EEGs.

BETS

● Also called small-sharp spikes ● Low in amplitude -~50 μV ● Morphology can be monophasic or diphasic ● Appear during drowsiness and light sleep in adults ● BETS do not run in trains, distort the background, or coexist with rhythmic slowing ● BETS diminish with deepening sleep ● Epileptiform discharges worsen with deeper sleep stages

Stage 3 Sleep

● Characterized by high voltage, high amplitude, slow delta and theta waveforms ● 20% delta activity ● Sleep Spindles and K complexes may be present ● As Stage 3 progresses the EEG frequencies become slower and occurrence of sleep spindles decrease

Triphasic Waveform

● Classically are associated with hepatic encephalopathy (Liver waves) ● Frontally positive sharp transients ● Amplitude >70 microvolts ● Bilateral and occur in bursts of repetitive waves at 1-3 Hz

Sleep Spindles

● Occur at the onset of Stage 2 sleep ● Bursts of sinusoidal 12-14Hz activity ● Present over fronto-central regions (F3, F4, FZ, C3, C4, CZ) maximally ● Usually will not exceed 50μV ● May not be synchronous but should be symmetric and bilateral ● Can be present in Stage 3 sleep

Vertex Sharp (V) Waves

● Seen in sleep stages I and II. ● Usually biphasic with an initial negative phase followed by a smaller positive phase - but the morphology may vary ● Occur synchronously over both hemispheres with a phase reversal at the sagittal leads ●Often exceed 100μV

Types of Partial (focal, localized seizure)

● Simple Partial Seizure ● Complex Partial Seizure

Stage 4 Sleep

● Stage 4 has been rolled into NREM 3 for PSG ● 50% or more delta activity ● Sleep Spindles are absent ● EEG consist of generalized high voltage (>75μv/mm), irregular shaped slow waves

Fourteen-and 6-Hz Positive Bursts

● These variants occur as bursts of rhythmic arched waves ● Trains occur at 14 and 6 Hz ● Bursts last only 0.5 to 1 sec. ● Maximal at the posterior temporal regions and usually occur independently from bilateral hemispheres with shifting predominance ● This variant appears in 10 to 58% of healthy subjects: ● Influenced by age, montage, and duration of drowsiness and sleep ● More prevalent in children and adolescents

Mu

● This occurs in waking over the central regions, especially the C3, CZ, and C4(Fig. 2) ● Mu exhibits a frequency in the alpha range, typically at 9 to 11 Hz. ● 14% of adolescents' EEG tracings ● Less often in younger children and the elderly ● Attenuates with contralaterallimb movement or just planned movement of the contralaterallimb.●

K Complexes

● Usually appear in Stage 2 sleep but may be seen in Stages 3 and 4 sleep ● High voltage transients (similar to V waves) with sleep spindles superimposed ● Can exceed 400μV in amplitude ● Can exceed 1000ms in duration ● Can be elicited by an auditory stimulus (example -tapping a pen) or other arousal stim

REM (Rapid Eye Movement)

● Usually begins 60-90 minutes after sleep onset ● Loss of muscle tone (except breathing and eye muscles) ● Respirations and heart rate are irregular ● Phasic Twitches- small muscle movements of face and extremities may be seen ● Saccadic eye movements (bursts of quick eye movements) ● Sawtooth waves, also called shark tooth waves

What is seen in a normal adult wake EEG?

● alpha ● eyes blinking, open and closed ● high muscle tone

What is seen in a normal adult drows EEG?

● alpha drops out ● eyes rolling ● muscle diminishes ● vertex sharp waves appear (v-waves)

EEG asymmetry

● refers to a difference in EEG amplitude between homologous areas of the head ● May be secondary to poor electrode placement ● May be caused by a skull defect

What are stimulation methods?

● touch ● sound ● visual

SUDEP is more likely in people:

● with uncontrolled tonic clonic (grandmal) seizures ● Those who take multiple antiepiletic drugs ● Those who are not taking adequate doses of antiepilitic medications