Diagnostic Value of Intermittent Photic Stimulation Among Adult Patients in a Tertiary Referral Epilepsy Center: A Retrospective Study.

PURPOSE: Photosensitivity is a phenomenon that may be elicited by standardized intermittent photic stimulation during EEG recording and is detected more frequently in children and adolescents. Nevertheless, at our Epilepsy Center, we routinely assess photosensitivity in all newly referred adult patients. In this investigation, we sought to address the diagnostic yield under the prerequisites described. METHODS: We reanalyzed all routine EEG recordings among referrals to the department of adults during the first six months of 2019, including a simultaneous video that is always coregistered in our center. The prevalence of abnormal findings during photic stimulation was assessed. RESULTS: Intermittent photic stimulation was performed on 344 patients. Photoparoxysmal response were detected in five subjects (1.5%). All patients were female. Four patients were diagnosed with idiopathic generalized epilepsy, and one with Doose syndrome. Photomyogenic responses were recorded in 1.1% and only in patients with psychogenic nonepileptic seizures. In two subjects with psychogenic nonepileptic seizures, the typical seizure was provoked by intermittent photic stimulation (8.7% of all subjects with psychogenic nonepileptic seizures in this cohort). Photoparoxysmal response was not detected in any subject with focal epilepsy, syncope, or other nonepileptic paroxysmal events. In every case of photoparoxysmal responses, increased photosensitivity had already been reported before recording. CONCLUSIONS: In our study, photoparoxysmal responses was a rare phenomenon among adults with a preponderance of females and idiopathic generalized epilepsies. Intermittent photic stimulation may be helpful in provoking typical psychogenic nonepileptic seizures and thus abbreviate the diagnostic process. Provided a careful history, routine intermittent photic stimulation in adults with epilepsy does not appear to be mandatory.

Clinical experience of abrupt discontinuation of perampanel: a case series.

With an elimination half-life of 105 hours, perampanel (PER) allows a once-daily dosing regimen. In pivotal trials, when PER was tapered, it was therefore usually discontinued abruptly. Thus, in our hospital we have always practiced abrupt cessation. In this case series, we investigated how long PER serum concentrations still remain measurable after abrupt discontinuation of PER and whether withdrawal symptoms, such as an increase in seizures or status epilepticus, occur. PER serum levels and the clinical course of 15 adult in-patients were monitored for three weeks based on a retrospective study design following abrupt discontinuation of PER. After one week, PER was still detected in 13 of 15 patients, after two weeks in 10, and after three weeks in three. Neither a severe increase in seizure frequency nor status epilepticus occurred. However, modifications of the concomitant antiseizure drugs were necessary. The abrupt discontinuation of PER leads to a slow decrease in plasma concentration, thus resembling self-evident gradual discontinuation of PER. In some cases, PER may still be measurable and thus clinically active even weeks after its discontinuation. Efficacy and safety of other antiseizure drugs can be estimated appropriately only thereafter.

Is brivaracetam-induced elevation of carbamazepine-epoxide levels common and clinically relevant? - A case series.

Brivaracetam (BRV) was recently introduced for the treatment of patients with focal epilepsy. BRV undergoes relatively few interactions, but one of them leads to the elevation of carbamazepine (CBZ)-10,11-CBZ-epoxide (CBZ-E) if BRV is co-administered with CBZ. This interaction has been considered to be clinically negligible. We present a case series of nine patients. In eight of them, levetiracetam (LEV) was switched to BRV. In the remaining case, oxcarbazepine was replaced by CBZ and added to a stable BRV dose. A marked increase of CBZ-E occurred in every case and was associated with clinically relevant symptoms including blurred vision, diplopia, dizziness, or fatigue in three of them. However, in the remaining six, the elevated CBZ-E levels were not associated with any tolerability problems. The importance of CBZ-E for adverse events under CBZ may have been overemphasized in the past and is not clinically impairing in most cases treated with the combination of BRV and CBZ.