PERIODIC DISCHARGES Flashcards
WHAT TYPE OF EPILEPSY?

Frequent asymptomatic left temporal spike-and-slow waves in localization-related epilepsy (LRE).
_________________are characteristically seen in acute (or subacute), pathological processes associated with a unilateral hemispheric structural lesion
Periodic lateralized epileptiform discharges (PLEDs)
PLEDs may appear as a physiological condition exacerbated by chronic conditions such as following seizures or rarely___________
migraine
WHAT IS THE LESION?

Left temporal PLEDs in a patient with left temporal lobe
epilepsy immediately following serial complex partial seizure
WHAT IS THE LESION?

Left temporal PLEDs plus in a patient with an acute occipital ischemic infarction. Note the rhythmic ictal discharge abutting the discharge
____________are most often associated with encephalopathy and typically occur as an epiphenomena of a severe bilateral disturbance of cerebral dysfunction.
Generalized periodic epileptiform discharges (GPEDs)
WHAT IS THE LESION?

Generalized periodic epileptiform discharges. This ictal pattern followed a prolonged seizure. Note the high amplitude of the discharges
The hallmark of ___________is the presence of pseudoperiodic slow complexes or PLEDs in the setting of symptoms that suggest a central nervous system infectious disease
herpes simplex encephalitis (HSE)
WHAT LESION?

Right temporal PLEDs in a patient with herpes encephalitis and nonconvulsive SE recorded in the ICU
Periodic discharges are the hallmark of ______________and occur in the majority of patients. The pattern is a pseudoperiodic generalized sharp wave that occurs with a diffuse slow background
Creutzfeldt-Jakob disease (CJD)
WHAT DISEASE?

CJD in a patient with encephalopathy and myoclonic jerks
High voltage (>300 μV) slow waves or sharp-and-slow wave complexes lasting 0.5 to 2.0 sec repeat every 4 to 10 sec in a very regular pattern, and may be provoked by hyperventilation or sleep early in the course of the disease. WHAT DISEASE?
Subacute sclerosing panencephalitis (SSPE
WHAT CONDITION IS IT ASSOCIATED?

SSPE (early) in a patient presenting with encephalopathy and periodic episodes of atonia
focal rhythmic ictal fast activity associated with periodic complexes (seen above), short intervals of recurrence, and abnormal background between discharges are clues that the periodic complexes are more likely to represent an___________
ictal phenomenon
The waveforms have three phases with a prominent high-voltage, surface-positive deflection sandwiched between a lower amplitude initial surface negative deflection and an aftergoing slower surface- negative potential
TRIPHASIC WAVES
WHAT EEG PATTERN

Triphasic waves noted on the EEG of another patient with
encephalopathy due to renal failure, who is on hemodialysis. The EKG however,
demonstrates ventricular fibrillation. The patient had a cardiac arrest and
died during long-term EEG monitoring.
__________pattern consists of stereotyped bursts, usually consisting of mixed frequencies with or without intermixed epileptiform discharges. The bursts usually recur between 2 and 10 sec and are separated by intervals of suppression That demonstrate no electrocerebral activity at normal
sensitivities.
The burst-suppression
__________suggests a severe bilateral cerebral dysfunction, and while nonspecific in etiology, when associated with hypoxia, This pattern suggests a poor prognosis
Burst suppression
WHAT EEG PATTERN?

Burst-suppression following out-of-hospital cardiac arrest.
The recording was obtained at 2 μV/mm with single electrode distances
_______________are bilateral periodic epileptiform discharges. They signify a diffuse encephalopathy and may occur with seizures, although frequently GPEDs occur as the expression of a diffuse structural injury pattern involving gray matter without seizures.
They are unreactive to somatosensory stimulation, and are associated with an absent or diffusely slow posterior dominant rhythm.
Generalized periodic epileptiform discharges (GPEDs)
WHAT PATTERN?

GPEDs in a 75-year-old man after cardiac arrest. He was comatose but had no clinical signs that were otherwise evident. Note the periodicity
_____________are less commonly associated with seizures than are periodic lateralized epileptiform discharges (PLEDs).
The discharges are bihemispheric and independent with different morphologies and periods of repetition and are less associated with seizures than are PLEDs or PLEDs pluS
Bilateral independent periodic epileptiform discharges (BiPLEDs)
WHAT PATTERN?

BiPLEDs in a 37-year-old HIV-positive man admitted following a prolonged generalized tonic-clonic seizure and meningoencephalitis.
Note the right frontal and left occipital bilateral independent hemispheric discharges.
__________may be composed of spikes, polyspikes, or sharp waves that are bilateral and synchronous at a rate of 0.5 to 1.0 Hz on a “flat” or low-amplitude recording and be associated with frequent myoclonic jerks (status myoclonus).
Generalized periodic epileptiform discharges (GPEDs)





