Prolongation of cortical sleep spindles during hippocampal interictal epileptiform discharges in epilepsy patients.

OBJECTIVE: Memory deficits are frequent among patients with epilepsies affecting the temporal lobe. Hippocampal interictal epileptic discharges (hIEDs), the presumed epileptic exaggeration of sharp wave-ripples (SWRs), are known to contribute to memory dysfunction, but the potential underlying mechanism is unknown. The precise temporal coordination between hippocampal SWRs and corticothalamic spindles during sleep is critical for memory consolidation. Moreover, previous investigation indicated that hIEDs induce neocortical spindlelike oscillation. In the present study, we aimed to assess the influence of hIEDs on neocortical spindles. METHODS: We analyzed the spindle characteristics (duration, amplitude, frequency) of 21 epilepsy patients implanted with foramen ovale (FO) electrodes during a whole night sleep. Scalp sleep spindles were categorized based on their temporal relationship to hIEDs detected on the FO electrodes. Three groups were created: (1) spindles coinciding with hIEDs, (2) spindles "induced" by hIEDs, and (3) spindles without hIED co-occurrence. RESULTS: We found that spindles co-occurring with hIEDs had altered characteristics in all measured properties, lasted longer by 126 ± 48 ms (mean ± SD), and had higher amplitude by 3.4 ± 3.2 µV, and their frequency range shifted toward the higher frequencies within the 13-15-Hz range. Also, hIED-induced spindles had identical oscillatory properties to spindles without any temporal relationships with hIEDs. In more than half of our subjects, clear temporal coherence was revealed between hIEDs and spindles, but the direction of the coupling was patient-specific. SIGNIFICANCE: We investigated the effect of hippocampal IEDs on neocortical spindle activity and found spindle alterations in cases of spindle-hIED co-occurrence, but not in cases of hIED-initiated spindles. We propose that this is a marker of a pathologic process, where IEDs may have direct effect on spindle generation. It could mark a potential mechanism whereby IEDs disrupt memory processes, and also provide a potential therapeutic target to treat memory disturbances in epilepsy.

Sleep alterations are related to cognitive symptoms in Parkinson's disease: A 24-hour ambulatory polygraphic EEG study.

BACKGROUND: Sleep disorders are frequent and early non-motor symptoms of Parkinson's disease (PD). As a consequence of histopathological changes, the regulation of rapid eye movement (REM) sleep is affected in PD causing REM sleep behaviour disorder in about half of the patients. Considering the well-known role of sleep in memory formation processes, our aim was to investigate the relationship between sleep alterations and cognitive performance to elucidate the possible association between sleep, and especially REM sleep changes and cognitive dysfunction in PD. METHODS: We investigated 25 PD patients and 20 healthy controls. All participants underwent a 24-hour-long 19-channel polygraphic EEG recording, neurological, neuroimaging and neuropsychological examination. The visually analysed sleep-EEG and neuropsychological data were statistically evaluated. RESULTS: The intergroup analysis showed significant decrease of REM and N3, but increase of N2 sleep ratio, and significantly lower scores in the verbal fluency in PD compared to healthy controls. While we found significant negative correlation between verbal fluency and REM-sleep in the whole sample, we observed a marginal significant correlation between phonemic fluency and REM sleep in the PD group. CONCLUSION: The negative correlation between verbal fluency performance and REM sleep duration suggests the role of decreased REM sleep in cognitive dysfunction in PD. The early involvement of REM sleep regulation with parallel executive dysfunction in PD emphasise the important role of REM sleep deterioration in the neurodegenerative process of PD.

Emotion recognition and theory of mind after temporal lobe epilepsy surgery: A systematic review.

In order to navigate in our complex social world successfully, it is crucial to maintain and practice cognitive skills that are dedicated to adaptive social functioning. Emerging evidence suggests that besides deficits in declarative memory, executive functions, and language, impairments in social cognition (SC, e.g., emotion recognition, theory of mind) are also present in temporal lobe epilepsy (TLE). The organic and psycho-social consequences of epilepsy surgery might have additional implications regarding this deficit. Here we qualitatively synthesize longitudinal and cross-sectional findings on SC after TLE surgery. A literature search using PubMed and Scopus identified 275 potential articles. Studies were eligible if they (1) included patients with a diagnosis of TLE, (2) included a healthy comparison group, (3) reported original research, (4) were published in peer-reviewed journals and in English language, (5) reported the intervention of epilepsy surgery. Articles that (1) were case studies, (2) did not focus on SC abilities, (3) used interviews or self-report questionnaires to examine SC functions were excluded. A total of 16 original studies assessing emotion recognition (ER) and/or theory of mind (ToM) matched our criteria. The literature suggests that neither ER nor ToM abilities change after surgery: post-surgery patients show similar impairment patterns to pre-surgery patients. Nevertheless, individual improvement or decline could be masked by group comparisons and results should be considered in light of methodological heterogeneity among studies.

Measurement of Food Losses in a Hungarian Dairy Processing Plant.

The phenomenon of food waste and food loss at any stage of the supply chain is significant in developed economies. The purpose of this article is to highlight the areas of milk processing where milk loss occurs, and, after quantifying the data obtained, reveal the extent of the losses. To achieve the goals, we conducted on-site visits to one of Hungary's milk processors. The methodology is based on the Food Loss and Waste (FLW) standard, accordingly we determined the extent of milk loss at the company level, supplemented with loss values by each dairy product. During the analyzed processing stages (receiving of raw milk, skimming, pasteurization, Extended Shelf-Life (ESL) milk, cheese milk, sour cream, yoghurt, and kefir) 1203.4-1406.8 L of raw material per day can be accounted as losses, which makes up 0.9-1% of daily production. A Milk Production-Milk Losses (MPML) model was created where six factors (technology and automation, design of the plant aspects, quantity of orders, expertise of employees, number of product variants, optimal storage capacity) were methodized that significantly influence the rate of milk losses over different time periods. Our paper highlights how areas of the production stage can be developed to decrease milk loss.

Influence of the postoperative inflammatory response on cognitive decline in elderly patients undergoing on-pump cardiac surgery: a controlled, prospective observational study.

BACKGROUND: The role of non-infective inflammatory response (IR) in the aetiology of postoperative cognitive dysfunction (POCD) is still controversial. The aim of this controlled, prospective observational study was to assess the possible relationship between the grade of IR, defined by procalcitonin (PCT) changes, and development of POCD related to cardiac surgery. METHODS: Forty-two patients, who were ≥ 60 years of age and scheduled for elective cardiac surgery, were separated into the low inflammatory (LIR) and high inflammatory (HIR) response groups based on their PCT levels measured on the first postoperative day. A matched normative control group of 32 subjects was recruited from primary care practice. The PCT and C-reactive protein (CRP) levels were monitored daily during the first five postoperative days. The cognitive function and mood state were preoperatively tested with a set of five neurocognitive tests and two mood inventories and at the seventh postoperative day. The Reliable Change Index modified for practice (RCIp) using data from normative controls was applied to determine the significant decline in test performance. RESULTS: The LIR (n = 20) and HIR (n = 22) groups differed significantly in the PCT (p < 0.001) but not in the CRP time courses. The incidence of POCD at the first postoperative week was 35.7% in the cohort. The LIR and HIR groups did not vary in the RCIp Z scores of neurocognitive tests and frequencies of POCD (7 vs 8 cases, respectively, p > 0.05). Additionally, there was no difference in the mood states, anxiety levels and perioperative parameters known to influence the development of POCD. CONCLUSIONS: In this study, the magnitude of the non-infective inflammatory response generated by on-pump cardiac surgery did not influence the development of POCD in the early postoperative period in elderly patients.

Current standards of neuropsychological assessment in epilepsy surgery centers across Europe.

We explored the current practice with respect to the neuropsychological assessment of surgical epilepsy patients in European epilepsy centers, with the aim of harmonizing and establishing common standards. Twenty-six epilepsy centers and members of "E-PILEPSY" (a European pilot network of reference centers in refractory epilepsy and epilepsy surgery), were asked to report the status of neuropsychological assessment in adults and children via two different surveys. There was a consensus among these centers regarding the role of neuropsychology in the presurgical workup. Strong agreement was found on indications (localization, epileptic dysfunctions, adverse drugs effects, and postoperative monitoring) and the domains to be evaluated (memory, attention, executive functions, language, visuospatial skills, intelligence, depression, anxiety, and quality of life). Although 186 different tests are in use throughout these European centers, a core group of tests reflecting a moderate level of agreement could be discerned. Variability exists with regard to indications, protocols, and paradigms for the assessment of hemispheric language dominance. For the tests in use, little published evidence of clinical validity in epilepsy was provided. Participants in the survey reported a need for improvement concerning the validity of the tests, tools for the assessment of everyday functioning and accelerated forgetting, national norms, and test co-normalization. Based on the present survey, we documented a consensus regarding the indications and principles of neuropsychological testing. Despite the variety of tests in use, the survey indicated that there may be a core set of tests chosen based on experience, as well as on published evidence. By combining these findings with the results of an ongoing systematic literature review, we aim for a battery that can be recommended for the use across epilepsy surgical centers in Europe.

[Operation - rehabilitation - employment]. / Mutét - rehabilitáció - munkavállalás.

In this article we would like to bring the attention to the importance of early rehabilitation, coordinated operation of different subdivisions of rehabilitation and the expanding opportunities after medical care through following a 38- year-old female patient's case who was operated 6 years ago with anaplasticus oligodendroglioma. We find it important that the experts working on the field of health care, social services or labour should be aware of the possibilities of rehabilitation of their patients from the capability assessment, through its development until their placement in integrated labour market. It is important, that even during the medical care both the client and their relatives receive proper information.

Increased mesiotemporal delta activity characterizes virtual navigation in humans.

Hippocampal theta or rhythmic slow activity (RSA) occurring during exploratory behaviors and rapid-eye-movement (REM) sleep is a characteristic and well-identifiable oscillatory rhythm in animals. In contrast, controversy surrounds the existence and electrophysiological correlates of this activity in humans. Some argue that the human hippocampal theta occurs in short and phasic bursts. On the contrary, our earlier studies provide evidence that REM-dependent mesiotemporal RSA is continuous like in animals but instead of the theta it falls in the delta frequency range. Here we used a virtual navigation task in 24 epilepsy patients implanted with foramen ovale electrodes. EEG was analyzed for 1-Hz wide frequency bins up to 10 Hz according to four conditions: resting, non-learning route-following, acquisition and recall. We found progressively increasing spectral power in frequency bins up the 4 Hz across these conditions. No spectral power increase relative to resting was revealed within the traditional theta band and above in any of the navigation conditions. Thus the affected frequency bins were below the theta band and were similar to those characterizing REM sleep in our previous studies providing further indication that it is delta rather than theta that should be regarded as a human analog of the animal RSA.

[Role of the intraoperative electrical brain stimulation in conserving the speech and language function in neurosurgical procedures on conscious patients]. / Az intraoperatív elektromos agyi stimuláció szerepe a nyelvi és beszédfunkciók megorzése céljából éber betegeken végzett idegsebészeti beavatkozások során.

AIM OF THE STUDY: To summarize the results gained with awake craniotomies, which were performed in either low grade glioma patients or epilepsy surgical patients whose tumor or epileptogenic zone, was in the vicinity of eloquent, mostly language, cortices. PATIENT SELECTION AND METHODS: In our retrospective study we selected 16 patients who were operated awake between 1999-2011 at the Neurosurgical Department of MAV Kórház Budapest, or at the National Institute of Neurosciences in Budapest, or at the Neurosurgical Department of the University of Debrecen in Debrecen. In the presurgical evaluation if it was possible we performed functional magnetic resonance imaging, tractography and detailed neuropsychological testing. At the National Institute of Neurosciences all patients were operated with the aid of MR guided neuronavigation. RESULTS: Anesthesia was carried out without complications in all of the 16 cases. Monitoring of sleep deepness has significantly contributed to the safety of anesthesia during the superficial anesthezied states of the operation. The intraoperative neuropsychological tasks used for testing language were sensitive enough to judge the little disturbances in speech during stimulation. Stimulation evoked seizures could be adequately managed during surgery and did not influence the outcome of the procedures. The use of neuronavigation helped significantly by planning the optimal place for the craniotomy and by intraoperative orientation. CONCLUSIONS: Awake craniotomies require well practiced surgical teams, which requires the cooperation of neuro-anesthesiologits, neurosurgeons, neuropsychologist and electrophysiologists. It has two goals, first to reduce the time of surgery to minimize surgical complications, secondly the detailed intraoperative mapping of cognitive and motor functions to avoid any neurological deficit. The intraoperative anatomical data provided by the neuronavigation and the functional data provided by awake intraoperative stimulation of the patient together serve the safety of the patient which is essential in the neurologically minimal invasive neurosurgical approach of the 21st century.

[Neuropsychological methods and trends in epilepsy management]. / Neuropszichológiai módszerek es irányvonalak az epilepsziaellátásban.

Neuropsychological assessment makes its own valuable contribution to diagnosis in epilepsy, and the integration of those findings with the data from multiple sources provides the most comprehensive picture for a given epilepsy patient. The objective of this paper is to define and summarize the role and methods of neuropsychological assessment, and to present recommendations on themes for future clinical research in the neuropsychology of epilepsy.

Nonmanipulative proximal upper extremity automatisms lateralize contralaterally in temporal lobe epilepsy.

PURPOSE: Upper extremity automatisms are considered to be an ipsilateral seizure lateralizing sign in temporal lobe epilepsy (TLE). Herein we describe different types of contralateral upper extremity automatisms (CUEAs). METHODS: One hundred ninety-three video-(electroencephalography) EEG recordings of 59 patients were reviewed. Other than two patients who refused surgery, all patients underwent standardized temporal lobectomy with favorable postoperative outcome. Fifty-seven seizures of 21 patients were selected with CUEAs. We evaluated their electroclinical characteristics and their relation to other lateralizing motor symptoms. RESULTS: Two types of CUEAs were observed. Nonmanipulative, proximal upper extremity automatisms were seen unilaterally and contralaterally to the operated side. These automatisms were rhythmic; repetitive; and often occurred with a circulatory component resembling waving, flaunting, circling, or stirring movements. They occurred in 29 seizures (15%) of 11 patients (19%), in most seizures in the first half of the seizure, and never postictally, in various time sequences and combined with dystonic/tonic posturing or limb immobility. Manipulative/distal type of CUEAs occurred in 11 seizures (6%) of 7 patients (12%) on the unexpected contralateral side. These CUEAs were seen in all phases of the seizures, including in the postictal state. DISCUSSION: Nonmanipulative unilateral proximal upper extremity automatism is a reliable lateralizing sign to the contralateral hemisphere in TLE. This sign may be pathophysiologically related to dystonic/tonic posturing. Manipulative distal automatisms have less lateralizing value.

Long-term outcome after temporal lobe surgery--prediction of late worsening of seizure control.

We analyzed possible predictors of late worsening of seizure control in 94 adult patients who had anterior temporal lobectomy (ATL) from the Epilepsy Center of the National Institute of Psychiatry and Neurology, Budapest between 1985 and 2001. We evaluated data regarding epilepsy, presurgical evaluation, pre- and postoperative EEG, structural imaging, histology and operative complications. The mean follow-up was 6.1 years (range: 2-17 years). The outcome was measured as Engel class, the time to the first seizure and the longest seizure free period. Multiple regression analysis was used to assess predictors. Seizure free outcome was achieved in 72% of the patients 1-year after surgery. Eighty-seven percent of them remained seizure free at the second year of follow-up, 74% at the fifth, and 67% at the tenth year of follow-up. After 2 years of follow-up improvement was present in 3%, worsening in 18% of the patients. Factors associated with long-term worsening were: postoperative ipsilateral EEG spikes over the resected side, preoperative bilateral interictal discharges, cortical dysplasia of Taylor's type, and ictal contralateral propagation. In these patients, even in seizure free state, therapy reduction might be inappropriate.

Pilomotor seizures and status in non-paraneoplastic limbic encephalitis.

BACKGROUND AND AIMS: To describe an unusual clinical presentation of a patient with voltage-gated potassium channel Ab- positive, non-paraneoplastic limbic encephalitis. METHODS: We performed video-EEG monitoring, structural MRI, (18)F-FDG-PET, (1)H-MRS, neuropsychological testing and antibody serology. RESULTS: A 42-year-old male patient presented in an acute phase of non-paraneoplastic limbic encephalitis confirmed by MRI, with antibodies to voltage-gated potassium channels. His pilomotor status was pharmacoresistant to antiepileptic drugs, but responded to corticosteroid and azathioprine treatment. The MRI findings improved. The pilomotor seizures recurred when the immunosuppressive therapy was discontinued after 18 months. MRI at that time was consistent with hippocampal sclerosis. Complete seizure control was achieved after reintroduction of steroids. CONCLUSION: Pilomotor seizures were the predominant seizure type in this case of non-paraneoplastic limbic encephalitis. Immunosuppressive therapy may provide recovery including seizure control. However, long-term immunosuppression may be necessary to prevent relapse. Hippocampal sclerosis and chronic epilepsy might evolve as sequelae of limbic encephalitis.