EPILEPTIFORM ABN Flashcards
I______________ represent a distinctive group of waveforms that are characteristically seen in personS with epilepsy
Interictal epileptiform discharges (IED)
Abnormal focal interictal epileptiform discharges on EEG represent a heightened predisposition for the expression of__________
partial-onset seizures
WHAT IS THE PROBLEM?
Intracranial versus scalp recording (in the bottom six channels) during a presurgical evaluation of intractable epilepsy. Sensitivities in the top channels are 75 μv versus 7 μv/mm at the scalp. Note the absence of IEDs in the scalp EEG compared to the intracranial EEG where they occur at 1/sec.
WHAT IS THE PROBLEM?
Intracranial versus scalp recording (in the bottom six channels) during a presurgical evaluation of intractable epilepsy. Sensitivities in the top channels are 75 μv versus 7 μv/mm at the scalp. Note the absence of IEDs in the scalp EEG compared to the intracranial EEG where they occur at 1/sec.
WHAT ED ARE SEEN?
Different morphologies include sharp waves (seen during seconds 1 and 2), spikes and sharp waves (in second 3), polyspike-and-slow waves (in second 4), and spike-and-wave discharges (in the last second of the figure) recorded during an ambulatory EEG in a patient with epilepsy.
Both ______and _______waves are referred to as interictal epileptiform discharges (transients)
spikes
sharp
________are more “blunted” than spikes and are IEDs with a duration of 70 to 200 msec.
Sharp waves
WHAT IS THE PROBLEM?
EEG demonstrating a couplet of left anterior temporal spike and- slow waves.
Interictal epileptiform discharges (spikes and sharp waves) are almost always surface negative, generating the typical_________
negative phase reversal
___________often have a clinical association with complex partial seizures of temporal lobe origin more than 90% of the time
Anterior temporal spikes or sharp waves
WHAT IS SHOWN?
Bilateral anterior temporal sharp-and-slow wave in drowsiness
Anterior temporal spikes or sharp waves often have a clinical association with ___________of temporal lobe origin more than 90% of the time
complex partial seizures
WHAT IS THE PROBLEM?
Left mid-temporal sharp wave in a patient with temporal lobe epilepsy. Note the focal theta and delta slowing regionally in the same region.
________also occur in patients with temporal lobe epilepsy (TLE). In general, they are often more regional in distribution with neocortical TLE
Mid-temporal IEDs
____________also called rolandic epilepsy) is a common childhood idiopathic localization-related epilepsy syndrome
Benign childhood epilepsy with centrotemporal spikes (BCECTS;
WHAT IS THE PROBLEM?
Left centroemporal spikes in a patient with BCECTS. Notice the central field of spread of the spikes and low-amplitude right frontal positivity.
The characteristic tangential or horizontal dipole that is formed in BCECTs demonstrates both a _____________during the discharge. This has been used to separate the more “benign” nature of BCECTs from a more pathological rolandic sharp wave
negativity and positivity
WHAT IS THE PROBLEM?
The same spikes depicted in Figure 3.7 demonstrated on linked ears reference montage. Note the frontal positivity denoting the tangential dipole of BCECTs
WHAT KIND OF EPILEPSY?
A right frontal spike and polyspike discharge in frontal lobe
epilepsy
Frontal spikes are often found in patients with ______________, although they may be absent in up to one-third of
patients.
frontal lobe epilepsy (FLE)
__________or diffuse discharges arising from a focal point in the frontal lobe may occur in up to twothirds of individuals with FLE
Secondary bilateral synchrony (SBS)
Some conditions may give rise to central spikes without epilepsy and include ________, _________, _________and normal variants (i.e., fragmented mu rhythm)
cerebral palsy, migraine, and inherited trait without seizures (i.e., siblings of those with BCECTS),
WHAT CONDITION IS SHOWN?
Right central spike-and-slow wave IEDs and focal slowing in a patient with a right frontal tumor and partial seizures.
WHAT IS THE PROBLEM?
Right central spike-and-slow wave IEDs and focal slowing in a patient with a right frontal tumor and partial seizures.
