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Background: In 2007, the AASM Manual for the Scoring of Sleep and Associated Events was published by the American Academy of Sleep Medicine (AASM). Concerning the visual classification of sleep stages, these new rules are intended to replace the rules by Rechtschaffen and Kales (R&K)., Methods: We adapted the automatic R&K sleep scoring system Somnolyzer 24 × 7 to comply with the AASM rules and subsequently performed a validation study based on 72 polysomnographies from the Siesta database (56 healthy subjects, 16 patients, 38 females, 34 males, aged 21-86 years). Scorings according to the AASM rules were performed manually by experienced sleep scorers and semi-automatically by the AASM version of the Somnolyzer. Manual scorings and Somnolyzer reviews were performed independently by at least 2 out of 8 experts from 4 sleep centers., Results: In the quality control process, sleep experts corrected 4.8 and 3.7% of the automatically assigned epochs, resulting in a reliability between 2 Somnolyzer-assisted scorings of 99% (Cohen's kappa: 0.99). In contrast, the reliability between the 2 manual scorings was 82% (kappa: 0.76). The agreement between the 2 Somnolyzer-assisted and the 2 visual scorings was between 81% (kappa: 0.75) and 82% (kappa: 0.76)., Conclusion: The AASM version of the Somnolyzer revealed an agreement between semi-automated and human expert scoring comparable to that published for the R&K version with a validity comparable to that of human experts, but with a reliability close to 1, thereby reducing interrater variability as well as scoring time to a minimum., (Copyright © 2010 S. Karger AG, Basel.)

Aim: The aim of the present study was the evaluation of actigraphy as a tool to objectify the recovery process after motor paresis due to stroke., Methods: The motor activity of both arms of patients suffering from stroke was actigraphically recorded at four different time points during the course of rehabilitation: 24-36 h, 5-7 days, 3 months, and 6 months after stroke., Results: Motor activity monitored by wrist-worn actigraphs located at the impaired side revealed an increase in activity between the first two time points and the subsequent ones. Additionally, actigraphic recordings showed lower total motor activity at the impaired side as compared to the nonimpaired side. A significant positive correlation was found between the actigraphically recorded motor activity and the results of the Scandinavian Stroke scale, the Barthel Index, the Rankin Scale Score and with the Motoricity Index during the 1st week, which corresponds to the time when neurological deficits were most pronounced., Conclusion: Our results suggest that actigraphy is a useful tool in the objective evaluation of motor activity after stroke. Moreover, actigraphy covers additional aspects that are not reflected by the usual stroke scales in a clinical situation., (Copyright 2008 S. Karger AG, Basel.)

To date, the only standard for the classification of sleep-EEG recordings that has found worldwide acceptance are the rules published in 1968 by Rechtschaffen and Kales. Even though several attempts have been made to automate the classification process, so far no method has been published that has proven its validity in a study including a sufficiently large number of controls and patients of all adult age ranges. The present paper describes the development and optimization of an automatic classification system that is based on one central EEG channel, two EOG channels and one chin EMG channel. It adheres to the decision rules for visual scoring as closely as possible and includes a structured quality control procedure by a human expert. The final system (Somnolyzer 24 x 7) consists of a raw data quality check, a feature extraction algorithm (density and intensity of sleep/wake-related patterns such as sleep spindles, delta waves, SEMs and REMs), a feature matrix plausibility check, a classifier designed as an expert system, a rule-based smoothing procedure for the start and the end of stages REM, and finally a statistical comparison to age- and sex-matched normal healthy controls (Siesta Spot Report). The expert system considers different prior probabilities of stage changes depending on the preceding sleep stage, the occurrence of a movement arousal and the position of the epoch within the NREM/REM sleep cycles. Moreover, results obtained with and without using the chin EMG signal are combined. The Siesta polysomnographic database (590 recordings in both normal healthy subjects aged 20-95 years and patients suffering from organic or nonorganic sleep disorders) was split into two halves, which were randomly assigned to a training and a validation set, respectively. The final validation revealed an overall epoch-by-epoch agreement of 80% (Cohen's kappa: 0.72) between the Somnolyzer 24 x 7 and the human expert scoring, as compared with an inter-rater reliability of 77% (Cohen's kappa: 0.68) between two human experts scoring the same dataset. Two Somnolyzer 24 x 7 analyses (including a structured quality control by two human experts) revealed an inter-rater reliability close to 1 (Cohen's kappa: 0.991), which confirmed that the variability induced by the quality control procedure, whereby approximately 1% of the epochs (in 9.5% of the recordings) are changed, can definitely be neglected. Thus, the validation study proved the high reliability and validity of the Somnolyzer 24 x 7 and demonstrated its applicability in clinical routine and sleep studies.

Objectives: Recent reports have led to the hypothesis of a central nervous system involvement in myasthenia gravis (MG). As the central cholinergic system also plays an important role in sleep/wake rhythms and in the regulation of REM sleep, sleep perception and dreaming may be altered in MG patients., Patients and Methods: Seventeen consecutive patients with MG (mean age 49.5 +/- 13.6 years) and 14 healthy controls (mean age 50.5 +/- 16.0 years) were investigated by means of the Self-Rating Depression Scale, Self-Rating Anxiety Scale, Quality of Life Index, Pittsburgh Sleep Quality Index, and Epworth Sleepiness Scale as well as a self-rating questionnaire for sleep and awakening quality and dreaming for 2 weeks., Results: Subjective sleep and awakening quality and sleep efficiency were reduced (p < 0.05), and the number of nocturnal awakenings (p = 0.02) as well as dream recall frequency (p = 0.02) were increased in patients with MG. Patients reported more often body-related and tactile sensations during dreaming (p = 0.001) and dreamed less often visually (p = 0.04). Dream content, emotions, and dream sources did not differ between both groups. Whereas the number of awakenings was related to dream recall frequency in healthy controls, no such a relationship was found in the patient group., Conclusion: There is no clear evidence for the arousal-retrieval model of dream recall in patients with MG, but more for the continuity hypothesis of dreaming. Other factors such as the functional state of the brain, possibly related to a central cholinergic involvement in MG or its anticholinesterase treatment, may be important in explaining dream recall in this patient group., (Copyright 2004 S. Karger AG, Basel)

Dopaminergic agents such as ropinirole are the drugs of first choice in treating restless legs syndrome (RLS). Recently, gabapentin, a structural analogue of gamma-aminobutyric acid, has also been shown to improve sensorimotor symptoms in RLS. Therefore, the tolerability and efficacy of randomized treatment with either gabapentin or ropinirole in patients with idiopathic RLS was evaluated in this 4-week open clinical trial. Patients with idiopathic RLS were treated with either 300 mg of gabapentin (n = 8) or 0.5 mg of ropinirole (n = 8) as the initial dose, and the dose was up-titrated until relief of symptoms was achieved (gabapentin mean dosage 800 +/- 397 mg, range 300-1,200 mg; ropinirole mean dosage 0.78 +/- 0.47 mg, range 0.25-1.50 mg). In both groups, International Restless Legs Syndrome Study Group questionnaire scores improved significantly (p < or = 0.018), whereas the scores of the Epworth sleepiness scale remained unchanged within normal limits. Polysomnographic data showed a reduction of periodic leg movements during sleep (PLMS; p < 0.03) and PLMS index (p < 0.02) in both groups. Side effects were only mild and mostly transient. After 6-10 months of follow-up, in most patients, RLS symptoms were still improved. We conclude that gabapentin and ropinirole provide a similarly well-tolerated and effective treatment of PLMS and sensorimotor symptoms in patients with idiopathic RLS., (Copyright 2003 S. Karger AG, Basel)

A group of young patients with insulin-dependent diabetes mellitus (n = 14; 8 men, 6 women; 33.1 +/- 8.9 years) were examined by topographic EEG mapping under normoglycemic and hypoglycemic conditions (glucose levels after intravenous insulin injection down to 32.6 +/- 7.6 mg/dl). From the clinical aspect, 7 of them had a good and 7 had a poor awareness of hypoglycemia. During hypoglycemia, a decrease in alpha activity (p < 0.05), an increase in delta (p < 0.05), and especially in theta activity (p < 0.05) were found. The most sensitive parameter was the alpha/theta ratio. In the range of slight hypoglycemia (50-60 mg/dl) the increase in delta and theta activity showed a topographic maximum in lateral frontal regions. During deep hypoglycemia there was a topographic maximum of slow frequencies in posterior parts of the brain (centrotemporal to parieto-occipital regions). The differences between the group with good and with poor awareness of hypoglycemia were most pronounced during slight hypoglycemia in C3, C4, and Pz (p < 0.05). At lower glucose levels group distinction was no longer possible. These EEG changes correspond to a temporary organic brain syndrome.

Within a double-blind, comparative study on the effects of the long-half-life benzodiazepine (BDZ), quazepam, and the short-half-life BDZ, triazolam, on clinical symptomatology, sleep and anxiety of 45 patients with insomnia based on a mild to moderate generalized anxiety disorder (GAD) (ICD-9 code: 307.42-1, 300,0; ASDC-APSS-Code: A.2.a), we compared, in a first step at baseline, drug-free polysomnographic and psychometric data of 22 patients recorded in the laboratory (L-group) and 21 patients recorded by the Oxford Medilog 9000 system at home (H-group) with those of normal controls. Sleep efficiency, total sleep time, wake within total sleep period (middle insomnia) and wake before buzzer (late insomnia) were significantly deteriorated in both patient groups as compared with controls, while sleep induction time only differed significantly in home recordings. Regarding sleep architecture, stage (S)2 was reduced, S3 and S4 increased in the H-group only, while no intergroup differences were seen in S1, SREM and REM latency. Subjective sleep quality was reduced in both patient groups, but not awakening quality. Psychometric tests in the morning demonstrated for the noopsyche, only a significantly deteriorated psychomotor activity in both patient groups. In the thymopsyche, evening well-being and mood in the morning were reduced in both the L- and H-group, affectivity and morning well-being only in the H-group. The psychopharmacological part of the study was completed by 40 patients (there were 4 drop-outs in the triazolam, 1 in the quazepam group). They were treated after 1 week placebo with either 15-30 mg (median 15 mg) quazepam or 0.25-0.5 mg (median 0.25 mg) triazolam for 4 weeks, and thereafter for 2 weeks with placebo. Anxiety (rated by HAMA and SAS) improved significantly with both drugs and remained improved throughout 2 weeks post-drug placebo, with quazepam being slightly superior to triazolam. Polysomnography demonstrated a shortened sleep onset only after quazepam. Sleep efficiency improved after acute administration of both drugs, but the improvement was maintained by quazepam only (tolerance development with triazolam). Rebound insomnia was observed only in the 1st post-triazolam placebo night (significant intergroup difference based on confirmatory testing). S2 increased, S3 + S4 decreased under and after quazepam, which represents a normalization in home-recorded GAD patients. S1 decreased with both drugs, SREM only under quazepam. Subjective sleep quality behaved very similarly to objective sleep efficiency. Awakening quality improved after acute therapy with both drugs, somatic complaints only with quazepam.(ABSTRACT TRUNCATED AT 400 WORDS)

Somatosensory-evoked potentials (SEPs) after median nerve stimulation were recorded in 10 neurologically normal patients during cardiopulmonary bypass and hypothermia. In all patients the changes of the latencies (spinal N13, cortical N20 and N35) and the central conduction time during cooling, and the decrease in latencies during rewarming was described by a gamma function. The analytic discussion of pooled data of all patients led to another SEP-latency-temperature relationship than the observation of each single patient. In 6 of 10 patients there was found a maximum of latency increase before the minimal temperature was reached. The cooling and the rewarming curve had to be considered separately. Latency changes of SEPs during hypothermia are discussed as a very complex phenomenon influenced by many technical and patient factors. This reduces the value of SEPs as an index of central nervous system integrity during open heart surgery and hypothermia.

The brain function of 60 patients undergoing open-heart surgery (36 patients receiving coronary artery bypass, 21 patients valve replacements, 3 both) was investigated before and 10 days after the operation utilizing topographic brain mapping of the electroencephalogram (EEG). The postoperative EEG changes were characterized by a slight delta-theta increase, an alpha decrease [especially in the fast alpha (10.5-13 Hz) band] and a beta increase in the relative power. The total power and the absolute power of the delta-theta, alpha and beta showed a decrease, the dominant frequency a significant slowing from 9.7 to 9.3 Hz. The centroid of alpha and beta activity decreased as well. These results are similar to findings obtained in patients with organic brain syndrome. The EEG changes were prominent over the left hemisphere, which may be of particular clinical relevance.

We examined 32 epileptics (20 female; 12 male; aged 6-73 years) who had displayed photoconvulsive reactions to flickering light in the EEG; they were examined with regard to their risks of getting epileptic seizures upon watching television (TV) under certain conditions. On a colour TV set each patient was shown a 3-min videofilm with slow- and fast-moving parts under 16 different conditions. The conditions had the following variables: (1) colour - monochrome; (2) dark room - light room, and (3) four different distances from the screen. In addition, each patient was subjected for 3 min to manipulated image interferences, including the vertical rolling of the picture. The results of this TV stimulation were always negative, i.e. in no patient did TV provoke a reproducible paroxysmal discharge in the EEG, nor was there any epileptic seizure. Our findings are discussed in connection with the corresponding literature.

In 19 patients with definite multiple sclerosis (MS) brainstem auditory-evoked potentials (BAEP) with paired stimuli were recorded. Only hearing pathways without abnormalities in usual BAEP were examined. The latencies of wave III and wave V were significantly increased with the paired-stimulus technique (using paired-click intervals of 1.5 and 4.0 ms duration) compared to single clicks. In 4 patients (21%) paired-click BAEP latencies exceeded the critical values of normal subjects. This technique might give new possibilities in detecting minor lesions in MS patients.

In 11 female patients with primary biliary cirrhosis, clinical and or electrophysiological signs of a polyneuropathy were found in 9 cases. 8 patients had clinical and 7 patients electrophysiological signs of a polyneuropathy. We derive from the significant correlations between neurographic and metabolic parameters that a hepatic disorder, a disorder of lipid and protein metabolism strongly contribute to the development of polyneuropathy in primary biliary cirrhosis.

Psychopathology, psychometric variables, central arousal and time experience were studied in 30 hyperthyroid female outpatients. While these patients could be significantly discriminated in several of the above-described measures during the acute state of the disease, the intergroup differences disappeared after thyreostatic therapy. The thyroxine level was correlated with elevated beta-activity and the latter with variables of psychopathology and time experience. Hormonal dysbalance in hyperthyroidism is discussed as a biological substrate for neurophysiological changes which in turn causes deterioration in mood and behavior.