Diagnostic Considerations
Among psychogenic symptoms, PNES are unique in one principal characteristic. With EEG video monitoring, they can be diagnosed with near certainty. This is in sharp contrast to other psychogenic symptoms, which are almost always a diagnosis of exclusion.
This unique feature allows a clarity and confidence of diagnosis that may assist in the critical step of convincing the patient and family of the nonorganic nature of the PNES.
In areas where EEG video monitoring is not available, clinicians can used a staged approach for diagnosis developed by the task force of the International League Against Epilepsy. [20] The task force proposed the following four categories of certainty for PNES diagnosis:
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Documented PNES – confirmed by clinical history plus EEG video monitoring
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Clinically established PNES – defined by clinical history, clinician witness, and EEG recording of habitual events without video
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Probable PNES – determined by clinical history, clinician witness of video or live events, and a normal EEG
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Possible PNES – relies on patient’s self-report of clinical events and a normal EEG
Differential Diagnoses
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Ambulatory Electroencephalography (EEG)
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Dizziness, Vertigo, and Imbalance
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Driving and Neurological Disease
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EEG Seizure Monitoring
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Psychogenic nonepileptic attacks. The event is provoked by an induction (or provocative) technique. Note the typical irregular nonclonic nontonic and asynchronous movements (including bicycling) with stop-and-go phenomenon.
