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Understanding SREDA on EEG

SREDA is an EEG finding that you may encounter in your pediatric work. It happens more often in adults over the age of 50 years; but can happen in the pediatric world too. Subclinical Rhythmic Electrographic Discharges (SREDA) are a type of EEG finding that can be seen in patients who do not have clinical seizures, but who may be at risk for developing seizures in the future.

SREDA is characterized by rhythmic, high-amplitude discharges that occur at a frequency of 2-3 Hz in the temporal regions of the brain. While SREDA is often asymptomatic, it can be associated with certain clinical conditions such as febrile seizures, encephalopathy, and cerebral palsy. In some cases, SREDA may be a precursor to clinical seizures, and patients with SREDA may benefit from close monitoring and treatment to prevent the development of seizures.

If you encounter SREDA on EEG in your work, it's important to understand that the management of SREDA depends on the underlying cause. If SREDA is associated with a clinical condition such as encephalopathy or cerebral palsy, treatment will focus on managing the underlying condition. If SREDA is believed to be a precursor to seizures, treatment may include antiepileptic medications or other interventions to prevent the development of seizures. – Testing the patient during runs is important. If unsure about a run, alerting the on-call neurologist about the run is helpful.

EEG Waveforms


EEG Waveforms


Other things to consider regarding SREDA:

  • Abrupt onset and termination, unlike seizures which evolve

  • Rhythmic, sharply contoured theta

  • May evolve slow to fast (from 1-2Hz to 5-6Hz) like a “seizure in reverse”

  • Duration: 20 secs to a few minutes

  • Usually bi-synchronous and symmetric

  • Temporal-parietal, distribution (in adults)

  • Widespread or bilateral, maximal posteriorly (in adults)

  • Runs typically occur at rest or in the drowsy state

EMU EEG Report Findings

EEG Diagnosis:

  1. Normal awake and asleep

  2. Subclinical rhythmic discharge of adult/child (SREDA; a benign variant)

  3. Clinical Events: None

History: This is a 3-year old who has been having episodes of unresponsiveness.

Medications: Onfi and Topamax

EEG Description (portions only): The patient was awake for an adequate period of time during the recording. The posterior background rhythm with eyes closed was of moderate voltage of 30 microvolts and 6-7 Hz that was reactive to eye opening and closure. The patient became drowsy during the study and was able to achieve deeper stages of sleep with symmetric sleep transients. During drowsiness and lighter stages of sleep bi central and parasagittal predominant rhythmic theta activity was noted at times followed by slow wave, slow wave being partially secondary to movement and arousal.

I hope that this information is helpful to you in your work.

by "Sharp and Spike Finder"

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