Usefulness of prolonged video–EEG monitoring and provocative procedure with saline injection for the diagnosis of non epileptic seizures of psychogenic origin

Abstract

IVISS is a useful diagnostic tool since it was the only way to confirm the diagnosis of PNES in 32% of our patients. We suggest that investigation for the diagnosis of PNES should always include both a prolonged VEEGM and an IVISS test.

A systematic review of suggestive seizure induction for the diagnosis of psychogenic nonepileptic seizures

“…Although long-term VEEG is frequently referred to as the "gold standard", it is such only in terms of diagnostic confidence when positive, just as SSI is (LaFrance et al, 2013). A "gold standard" in terms of perfect (near 100%) sensitivity does not exist for PNES, since even long-term VEEG often remains inconclusive or negative in cases of suspected or confirmed PNES (Lancman et al, 1994;Moseley et al, 2015;Ribaï et al, 2006). Despite these and other methodological considerations (Lanska, 1994;Levine, 1994;Replogle et al, 2009) for the purpose of this review long-term VEEG was considered an adequate independent reference standard.…”

“…To assess the degree of deception involved in informing patients about SSI we classified the reported communication strategies into three categories: "explicitely deceptive", when a statement is made that is untruthful (e. g. "a seizure will be produced […] by placing a vibrating tuning fork on the forehead and sending 'electric vibrations' through the brain", Guberman et al, 1982); "truthful but omissive", when the information is technically truthful, but an exclusively organic process is still implied (e. g. "we will inject an IV drug that will perhaps help in inducing the usual spell […] We did not say the words 'epileptic seizure' in order to avoid lying to the patient", Ribaï et al, 2006); and "explicitely open", when the information provided is technically correct and a psychological process is explicitely introduced as a possiblity before SSI ("The possible occurrence of both epileptic and psychogenic seizures during hyperventilation and photic stimulation was stressed", Popkirov et al, 2015). M a n u s c r i p t 4…”

Errors in EEG Interpretation and Misdiagnosis of Epilepsy

“…A robust and replicated finding is that about 30% of patients seen at epilepsy centers for refractory seizures do not have epilepsy [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. Remarkably, the proportion of patients misdiagnosed is also similar in patients diagnosed as having posttraumatic epilepsy [18], patients referred directly (without EEG-video monitoring) for vagus nerve stimulation [19] and in patients awarded a ‘seizure alert dog’ [20].…”

Paroxysmal Disorders in Neuropsychiatry: Why Episodic Disorders Must be Accounted For

“…10-20 minutes) after a tonic clonic seizure or CPS and controversially simple partial may be elevated (inconsistent in 60%) [48][49][50][51][52][53].…”