Psychiatric complications following SEEG-guided radiofrequency thermocoagulations in patients with drug-resistant epilepsy.

SEEG-guided radiofrequency thermocoagulation (RF-TC) in the epileptogenic regions is a therapeutic option for patients with drug-resistant focal epilepsy who may have or not indication for epilepsy surgery. The most common adverse events of RF-TC are seizures, headaches, somatic pain, and sensory-motor deficits. If RF-TC could lead to psychiatric complications is unknown. In the present study, seven out of 164 patients (4.2 %) experienced psychiatric decompensation with or without memory deterioration after RF-TC of bilateral or unilateral amygdala and hippocampus. The appearance of symptoms was either acute, subacute, or chronic and the symptoms were either transient or lasted for several months. Common features among these patients were female sex, mesial temporal epilepsy, and a pre-existing history of psychological distress and memory dysfunction. Our study highlights the possibility of neuropsychiatric deterioration in specific patients following SEEG-guided RF-TC, despite its rarity.

"Plok-plok" syndrome: Posttraumatic stress disorder following an SEEG thermocoagulation and direct electrical stimulation procedure.

The psychological impact of intracerebral electroencephalography (stereoelectroencephalography [SEEG]) including the thermocoagulation procedure has not yet been clearly studied. We present a case of a patient who, following an SEEG procedure for presurgical evaluation of intractable focal epilepsy, developed severe symptoms of posttraumatic stress disorder. Such an occurrence may be under-estimated. Perceived traumatic exposure during SEEG and the development of posttraumatic psychological symptoms should be further studied in order to define risk factors and to improve the monitoring and psychological management of patients during their hospitalization. A careful and systematic procedure of prevention and support before, during, and after SEEG could decrease the risk of development or worsening of symptoms of anxiety, depression, and posttraumatic stress disorder.

Screening for epilepsy-specific anxiety symptoms: French validation of the EASI.

OBJECTIVES: (1) To translate and validate the Epilepsy Anxiety Survey Instrument (EASI) in French people with epilepsy (PWE); (2) to further investigate the screening properties of each dimension of the EASI in terms of Diagnostic and Statistical Manual of Mental Disorders (DSM) anxiety disorders and of epilepsy-specific anxiety disorders, namely, anticipatory anxiety of seizures (AAS) and epileptic social phobia. METHODS: Following back-translation, the French EASI was tested in PWE > 18 years using the Mini-International Neuropsychiatric Interview (MINI) as gold standard for DSM anxiety disorders. We added 3 original questions to explore epilepsy-specific anxiety symptoms. The Generalized Anxiety Disorders-7 (GAD-7), Neurological Disorders Depression Inventory for Epilepsy (NDDI-E), and Adverse Events Profile were performed for external validity. Receiver operator characteristics (ROC) were analyzed. RESULTS: One hundred and forty nine native French speakers with epilepsy were included. Concerning DSM disorders, around 25% had GAD, 18% Agoraphobia, and <10% Social Phobia or Panic Disorder. Concerning possible epilepsy-specific anxiety disorder, 35% had AAS and 38% had epileptic social phobia. Bi-dimensional structure of the EASI was confirmed. Internal and external validity was satisfactory. ROC analysis showed AUC of 0.83 for detection of GAD and AUC 0.79 for other DSM anxiety disorders. ROC analysis of the 8-item French brEASI showed good performance for detection of GAD (AUC 0.83) and other DSM anxiety disorders (AUC 0.76) but not for epilepsy-specific anxiety symptoms (AUC 0.63). Conversely, dimension 2 of the French EASI (=10 items) allowed good detection of epilepsy-specific anxiety symptoms (AUC 0.78); cutoff > 4, sensitivity 82.4, specificity 66.7. CONCLUSION: Epilepsy-specific anxiety symptoms were prevalent, in around 60%. The French version of the EASI showed robust performance. The French 8-item brEASI allows screening for all DSM anxiety disorders with superior performance than the GAD-7, but is less suited to screening for epilepsy-specific anxiety. We propose the "Epilepsy-Specific Anxiety" (ESA) 10-item screening instrument, based on dimension 2 of the EASI, as a complementary clinical and research tool.

De novo psychosis after left temporal lobectomy: a case of forced normalization?

Forced normalization is a clinical entity defined by the appearance of psychiatric disturbance following control of epileptic seizures that were previously uncontrolled. It was first described by Landolt in 1953. The first cases described were mostly psychosis, however, subsequent work suggested that any behavioural disturbance of acute/or subacute onset concomitant with seizure control could be considered as forced normalization. We report the case of a 65-year-old, right-handed Caucasian patient who was followed in the Epilepsy Centre of Marseille, for left temporal drug-resistant epilepsy. The frequency of seizures was one seizure per month at the time before surgery. Left anterior temporal lobectomy was proposed based on presurgical evaluation. The patient remained seizure-free after surgery, but he presented with an episode of acute psychosis three months after. At this point, EEG was performed, showing rare left temporal epileptiform activity mainly provoked by hyperventilation, with breach rhythm over the left temporal surgical. The appearance of acute psychosis after cessation of epileptic seizures and reduced epileptiform activity on the EEG led us to question the forced normalization process in this case. Another hypothesis would be the effect of surgery itself, since there is an increased risk of any psychiatric disturbance unrelated to seizure cessation during the postoperative period. In conclusion, psychosis in this case could have resulted from the combination of several factors, including the effect of surgery itself and seizure cessation. This case illustrates the need for specific psychiatric care in the perioperative period in patients with epilepsy.

Transient cortico-cortical disconnection during psychogenic nonepileptic seizures (PNES).

Psychogenic nonepileptic seizures (PNES) are paroxysmal clinical events that are often misdiagnosed as epileptic seizures, but which are not associated with electrographic discharge. Brain connectivity changes occurring during PNES are not known. We studied functional connectivity (Fc) in two patients with drug-resistant epilepsy, explored by stereotactic electroencephalography (EEG), in whom we recorded both epileptic seizures (ES) and PNES. Functional connectivity using pair-wise nonlinear correlation was computed between signals from seven brain areas: amygdala, hippocampus, lateral temporal cortex, anterior insula, orbitofrontal cortex, prefrontal cortex, and lateral parietal cortex. We assessed changes in global Fc during PNES in comparison with a background period. During PNES, a global decrease of Fc occurred between the different brain regions studied, compared with the interictal period. In both patients, decreased Fc was prominent in connections involving the anterior insula and parietal cortex. In conclusion, some PNES are associated with ictal functional disconnection between brain areas, particularly involving the parietal cortices and the anterior insula.

Alteration of global workspace during loss of consciousness: a study of parietal seizures.

PURPOSE: Loss of consciousness (LOC) in epileptic seizures has a strongly negative impact on quality of life. Recently, we showed that LOC occurring during temporal lobe seizures was correlated with a nonlinear increase of neural synchrony in associative--and particularly parietal--cortices. Whether these mechanisms might be observed in other types of seizures is unknown. This study aimed at investigating the relationship between changes in synchrony and degree of LOC during parietal lobe epilepsy (PLE), a form of epilepsy in which seizures directly involve the parietal associative cortices. METHODS: Ten patients undergoing stereoelectroencephalography (SEEG) during presurgical evaluation of PLE were studied. The LOC intensity was scored using the Conscious Seizure Scale (CSS). For each studied seizure (n = 29), interdependencies between signals recorded from six brain regions were estimated as a function of time by using nonlinear regression analysis (h(2) coefficient). KEY FINDINGS: Seizures were divided into three groups according to the CSS scale: group A (no LOC) with a score ≤1, group B (intermediate or partial LOC) with a score ranging from 2 to 5, and group C (maximal LOC) with a score ≥6. The majority of seizures in patients with PLE disclosed significant LOC (17/29, group C). Mean h(2) values were significantly different between the three groups (p = 0.008), the maximal values of synchrony being observed in group C. In addition, a statistically significant nonlinear relationship (p = 0.0021) was found between the h(2) values and the CSS scores, suggesting a threshold effect. SIGNIFICANCE: This study indicates that excess of EEG signal synchrony within associative cortices is likely to be a crucial phenomenon associated with LOC.

Impaired consciousness during temporal lobe seizures is related to increased long-distance cortical-subcortical synchronization.

Loss of consciousness (LOC) is a dramatic clinical manifestation of temporal lobe seizures. Its underlying mechanism could involve altered coordinated neuronal activity between the brain regions that support conscious information processing. The consciousness access hypothesis assumes the existence of a global workspace in which information becomes available via synchronized activity within neuronal modules, often widely distributed throughout the brain. Re-entry loops and, in particular, thalamo-cortical communication would be crucial to functionally bind different modules together. In the present investigation, we used intracranial recordings of cortical and subcortical structures in 12 patients, with intractable temporal lobe epilepsy (TLE), as part of their presurgical evaluation to investigate the relationship between states of consciousness and neuronal activity within the brain. The synchronization of electroencephalography signals between distant regions was estimated as a function of time by using non-linear regression analysis. We report that LOC occurring during temporal lobe seizures is characterized by increased long-distance synchronization between structures that are critical in processing awareness, including thalamus (Th) and parietal cortices. The degree of LOC was found to correlate with the amount of synchronization in thalamo-cortical systems. We suggest that excessive synchronization overloads the structures involved in consciousness processing, preventing them from treating incoming information, thus resulting in LOC.