Abstracts

Rationale: Distinguishing between psychogenic non-epileptic seizures (PNES) and epileptic seizures (ES) can be difficult. Misdiagnosis of PNES as ES carries significant risk of iatrogenic injury, increases the financial cost of care and delays appropriate treatment, leading to poorer long-term patient outcomes. The ‘gold standard’ investigation for diagnosing PNES is generally considered to be prolonged video-electroencephalogram (vEEG) monitoring. The tertiary epilepsy service at Cork University Hospital in Ireland serves a population of 1.6 million people. Following a two-year period without access to vEEG monitoring, a lengthy waiting list existed at the opening of the two-bedded epilepsy monitoring unit. The ubiquitous nature of smartphones with video-recording capability was recognised as a potential source of useful diagnostic information, as the identification of clusters of semiological features on video by an epileptologist may reliably differentiate PNES from ES. We evaluate the role of smartphone video-recordings in the diagnostic process for a cohort of adults with suspected PNES in the setting of limited access to prolonged vEEG monitoring.Methods: A retrospective analysis of all new adult cases of suspected PNES in the Rapid Access Seizure Clinic from October 2012 to February 2015. When home circumstances permitted, patients were asked to provide smartphone video-recordings of two or more habitual events. All patients and video recordings were reviewed by an epileptologist. Medical charts were reviewed to establish the diagnostic process and clinical outcome in each case.Results: 96 patients were identified with suspected PNES and 20 (20.83%) produced smartphone video-recordings which were considered diagnostic in every case – 15 PNES, two ES and three PNES with coexisting ES. Of the 15 patients with PNES, events resolved immediately in three after receiving the diagnosis; follow-up is pending for the other 12. The two patients with ES both showed improvement in event frequency with anti-epileptic drug (AED) introduction and clinical review is on-going. Of the three patients with PNES and coexisting ES, one patient underwent AED reduction and showed a reduced PNES frequency; follow-up is pending for the other two.Conclusions: Smartphone video recordings are diagnostically useful and can facilitate establishment of a definite diagnosis of PNES, ES and PNES with coexisting ES, obviating the need for prolonged inpatient video-EEG telemetry in some circumstances. The appropriate use of smartphone videos could facilitate more timely diagnosis of PNES and earlier referral to psychotherapy, potentially improving patient outcomes. Particular caution regarding the interpretation of video alone is required in cases of possible coexisting PNES and ES, frontal lobe ES and with events characterised by purely subjective episodic symptoms. Serial clinical review should be arranged to identify any features suggestive of an alternative diagnosis and follow-up for this cohort is on-going.