A European questionnaire survey on epilepsy monitoring units' current practice for postoperative psychogenic nonepileptic seizures' detection

Abstract

Background

In cases undergoing epilepsy surgery, postoperative psychogenic nonepileptic seizures (PNES) may be underdiagnosed complicating the assessment of postsurgical seizures' outcome and the clinical management.

We conducted a survey to investigate the current practices in the European epilepsy monitoring units (EMUs) and the data that EMUs could provide to retrospectively detect cases with postoperative PNES and to assess the feasibility of a subsequent postoperative PNES research project for cases with postoperative PNES.

Methods

We developed and distributed a questionnaire survey to 57 EMUs. Questions addressed the number of patients undergoing epilepsy surgery, the performance of systematic preoperative and postoperative psychiatric evaluation, the recording of sexual or other abuse, the follow-up period of patients undergoing epilepsy surgery, the performance of video-electroencephalogram (EEG) and postoperative psychiatric assessment in suspected postoperative cases with PNES, the existence of electronic databases to allow extraction of cases with postoperative PNES, the data that these bases could provide, and EMUs' interest to participate in a retrospective postoperative PNES project.

Results

Twenty EMUs completed the questionnaire sheet. The number of patients operated every year/per center is 26.7 ( ± 19.1), and systematic preoperative and postoperative psychiatric evaluation is performed in 75% and 50% of the EMUs accordingly. Sexual or other abuse is systematically recorded in one-third of the centers, and the mean follow-up period after epilepsy surgery is 10.5 ± 7.5 years. In suspected postoperative PNES, video-EEG is performed in 85% and psychiatric assessment in 95% of the centers. An electronic database to allow extraction of patients with PNES after epilepsy surgery is used in 75% of the EMUs, and all EMUs that sent the sheet completed expressed their interest to participate in a retrospective postoperative PNES project.

Conclusion

Postoperative PNES is an underestimated and not well-studied entity. This is a European survey to assess the type of data that the EMUs surgical cohorts could provide to retrospectively detect postoperative PNES. In cases with suspected PNES, most EMUs perform video-EEG and psychiatric assessment, and most EMUs use an electronic database to allow extraction of patients developing PNES.

Introduction

Psychogenic nonepileptic seizures (PNES) are paroxysmal events with motor manifestations and/or disturbances of sensation and responsiveness, which resemble epileptic seizures, without being related to epileptic discharges in the electroencephalogram (EEG) and not due to other readily identifiable pathophysiological changes [1,2].

Psychogenic nonepileptic seizures continue to represent a serious diagnostic challenge, and the diagnostic difficulties are enhanced by the fact that a proportion of patients have epilepsy and PNES concurrently or sequentially. If one condition follows the other, epilepsy is mostly the initial disorder [3,4]. Consequently, epilepsy can be considered as a risk factor for PNES development [3].

The de novo development of PNES has been described after brain surgery for indications other than refractory epileptic seizures, but, nevertheless, PNES are more likely to occur after epilepsy surgery [[5], [6], [7], [8], [9], [10], [11]].

This phenomenon is often underdiagnosed and underestimated, complicating the assessment of postsurgical seizures' outcome and the clinical management.

To obtain a clear picture of the entity, it is important to estimate postoperative PNES prevalence, assess potential risk factors as preoperative psychiatric disease, report the diagnostic procedures used for their detection, and identify characteristic PNES manifestations and associations.

The primary aim of our study was to assess the current practice and the data that the epilepsy monitoring units (EMUs) surgical cohorts could provide to retrospectively detect cases with postoperative PNES. Toward this goal, we developed and distributed a questionnaire to gather information from European EMUs regarding the data that they could provide for postoperative PNES detection.