[Acquired foot drop]. / Verworven klapvoet.

A dropping foot is the consequence of a variety of debilitating conditions and is oftentimes treated conservatively by general practitioners and other specialists. Typically, it is caused by peroneal nerve palsy secondary to compression or a hernia nucleosipulpei at the level L4-L5. Identifying the underlying pathology requires a neurological work-up oftentimes including ultrasound and electromyographic investigation. When a peroneal nerve compression is found, decompression can be achieved operatively. Should the underlying cause of the dropping foot have been treated adequately without an effect on the foot itself, then a posterior tibial tendon transfer may be considered. Generally, a posterior tibial tendon transfer has good outcomes for the treatment of dropping foot although it is partly dependent on the physiotherapy that accompanies it.

Safety and efficiency of medication withdrawal at home prior to long-term EEG video-monitoring.

PURPOSE: Long-term video-EEG monitoring (LTM) is frequently used for diagnostic purposes and in the workup of epilepsy surgery to determine the seizure onset zone. Different strategies are applied to provoke seizures during LTM, of which withdrawal of anti-epileptic drugs (AED) is most effective. Remarkably, there is no standardized manner of AED withdrawal. For instance, the majority of clinics taper medication during clinical admission, whereas we prefer to taper medication at home prior to admission. Our aim was to study the advantages (efficiency and diagnostic yield) and disadvantages (safety and complication rates) of predominantly tapering of medication at home. METHOD: We report a retrospective observational cohort of 273 patients who had a LTM at our tertiary epilepsy center from 2005 until 2011. Provocation methods to induce seizures were determined on individual basis. Success rate (duration of admittance, time to first seizure, efficiency and diagnostic yield) and complications and serious adverse events were assessed. RESULTS: AED were tapered in 180 (66%) patients, in 93 (24%) of these patients with additional (partial) sleep deprivation. In all of these patients tapering started at home one to four weeks prior to admission. In the other patients, only (partial) sleep deprivation or none provocation method at all was applied. Seizure recordings were successful in 79,9% of patients. Complications occurred in 19 patients (10.9%) of which 3 had (1.7%) serious adverse events (status epilepticus (SE)) with AED withdrawal. These complications only occurred during admittance, not at home. CONCLUSIONS: AED withdrawal at home prior to LTM is an efficient and convenient method to increase the diagnostic yield of LTM and appears relatively safe.

Morningness and eveningness: when do patients take their antiepileptic drugs?

Almost one-third of epilepsy patients continue to have seizures despite adequate drug treatment. Chronotherapy (based on dynamic changes in drug pharmacology and disease-related processes) could be a promising treatment option. We aimed to explore whether different circadian types adjust administration times of anti-epileptic drugs (AEDs) as a step in exploring chronotherapeutic possibilities. We performed a questionnaire-based study to compare behavior of different circadian types in relation to times of taking drugs. Circadian type was determined by the Morningness-Eveningness Questionnaire. Results clearly show that morning types are taking their AEDs significantly earlier than do evening types on free days. Times of taking AEDs in the morning on work days also differ significantly between morning and evening types. Regardless of circadian type, drugs on free days are taken later than on working days. In conclusion, our study shows that patients adapt times of taking medication to their circadian type.

Timing of temporal and frontal seizures in relation to the circadian phase: a prospective pilot study.

There is strong evidence that epileptic seizures occur in diurnal or 24-h patterns. A study in rat models of partial epilepsy showed circadian seizure patterns, and in humans circadian rhythmicity in interictal discharges has been found, suggesting that circadian rhythm may play a role in epilepsy. Circadian influences on human seizure patterns have not been investigated. We performed a pilot study to ascertain influences of the circadian rhythm on seizure occurrence. We prospectively outlined circadian rhythms of patients admitted for long term EEG and video monitoring, using measurement of the dim light melatonin onset (DLMO). Seizures during admission were recorded with continuous EEG and video monitoring. The DLMO ranged from 18:46h to 23:13h (mean 21:22h). One hundred and twenty-four seizures of 21 patients were analysed. Seizures of temporal lobe origin occurred mainly between 11:00 and 17:00h and frontal seizures were seen mostly between 23:00 and 05:00h. When correlating seizure timing to the individual's circadian phase as measured by the DLMO, the following was seen: temporal seizures occurred most frequently in the 6h before DLMO and frontal seizures mainly in 6-12h after the DLMO. The results of this pilot study suggest that temporal and frontal seizures occur in a non-random fashion synchronized to a hormonal marker of the circadian timing system.

Chronotypes and subjective sleep parameters in epilepsy patients: a large questionnaire study.

Accumulating evidence suggests epilepsy and seizures may influence circadian rhythms and that circadian rhythms may influence epilepsy. It is also conceivable that seizure timing influences the timing of daily activities, sleeping, and wakefulness (i.e., chronotype). Only one group has studied the distribution of chronotypes of epileptics, showing significant differences between the diurnal activity patterns in two groups of patients with different epilepsy syndromes. The authors performed a questionnaire-based study of 200 epilepsy patients to compare the distribution of chronotypes and subjective sleep parameters of sleep duration and time of mid-sleep on free days to the distribution in the general population (n = 4042). Within this large group of epilepsy patients, we also compared the chronotypes of subsamples with well-defined epilepsy syndromes, i.e., temporal lobe epilepsy [TLE; n = 46], frontal lobe epilepsy [FLE; n = 30], and juvenile myoclonic epilepsy [JME; n = 38]. In addition, 27 patients who had had surgery for TLE were compared with those with TLE who had not had surgery. Both the Morningness-Eveningness Questionnaire and Munich Chronotype Questionnaire were used to determine chronotypes and subjective sleep parameters. Significant differences in morningness/eveningness distribution, timing of mid-sleep (corrected for sleep duration), and total sleep time on free days were found between epileptics and healthy controls. Those with epilepsy were more morning oriented, had earlier mid-sleep on free days, and longer sleep duration on free days (p < .001). However, distributions of chronotypes and sleep parameters between the groups of people with TLE, FLE, and JME did not differ. Persons who had surgery for TLE had similar morningness-eveningness parameters and similar sleep durations compared to those without surgery, but mid-sleep on free days was earlier in operated patients (p = .039). In conclusion, this is the first large study focusing on chronotypes in people with epilepsy. We show that the distribution of chronotypes and subjective sleep parameters of epileptics, in general, is different from that of healthy controls. Nevertheless, no differences are observed between patients with specified epilepsy syndromes, although they exhibit seizures with different diurnal patterns. Our results suggest that epilepsy, itself, rather than seizure timing, has a significant influence on chronotype behavior and subjective sleep parameters.

Diurnal rhythms in seizures detected by intracranial electrocorticographic monitoring: an observational study.

Few studies have evaluated human seizure occurrence over the 24-hour day, and only one group has employed intracranial electrocorticography monitoring to record seizures. Circadian patterns in seizures may have important implications in diagnosis and therapy and provide opportunities in research. We have analyzed spontaneous seizures in 33 consecutive patients with long-term intracranial EEG and video monitoring. Several aspects of seizures were noted, including time of day, origin, type, and behavioral state (sleeping/awake). We recorded 450 seizures that showed an uneven distribution over the day, depending on lobe of origin: temporal lobe seizures occurred preferentially between 1100 and 1700 hours, frontal seizures between 2300 and 0500 hours, and parietal seizures between 1700 and 2300 hours. In the awake state, larger proportions of clinical seizures were seen from 0500 to 1100 hours and from 1700 to 2300 hours. During sleep, larger proportions occurred from 1100 to 1700 hours and from 2300 to 0500 hours. Our results suggest that seizures from different brain regions have a strong tendency to occur in different diurnal patterns.

Temporal distribution of clinical seizures over the 24-h day: a retrospective observational study in a tertiary epilepsy clinic.

PURPOSE: Very few studies have evaluated seizure occurrence in humans over the 24-h day; data from children are particularly scarce. Circadian patterns in seizure occurrence may be of importance in epilepsy research and may have important implications in diagnosis and therapy. METHODS: We have analyzed clinical seizures of 176 consecutive patients (76 children, 100 adults) who had continuous electroencephalography (EEG) and video monitoring lasting more than 22 h. Several aspects of seizures were noted, including classification, time of day, origin, and sleep stage. RESULTS: More than 800 seizures were recorded. Significantly more seizures were observed from 11:00 to 17:00 h, and from 23:00 to 05:00 h significantly fewer seizures were seen. The daytime peak incidences were observed in seizures overall, complex partial seizures (in children and adults), seizures of extratemporal origin (in children), and seizures of temporal origin (in adults). Incidences significantly lower than expected were seen in the period 23:00 to 05:00 h in seizures overall, complex partial seizures (in children and adults), and in tonic seizures (in children). In addition, significantly fewer seizures of temporal (in children and adults) and extratemporal origin (in children) were observed in this period. DISCUSSION: The results suggest that certain types of seizures have a strong tendency to occur in true diurnal patterns. These patterns are characterized by a peak during midday and a low in the early night.

How to assess circadian rhythm in humans: a review of literature.

It is well known that seizures of some types of epilepsy tend to occur in patterns. The circadian rhythm may play a significant role in this phenomenon. In animal studies it has been found that seizures in experimental partial epilepsy are probably under the influence of the biological clock. In this review an introduction to the influence of the human circadian rhythm in epilepsy is given. Furthermore, the methodology of measuring the circadian rhythm in humans is explored. An overview of widely used methods includes protocols used to desynchronize circadian rhythm, and sleep-wake and biological markers such as the dim light melatonin onset, core body temperature, and cortisol that are employed to determine the phase of the circadian rhythm. Finally, the use of sleep parameters, actigraphy, and questionnaires is discussed. These are also important in assessment of the circadian rhythm.