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Study Objectives Sleep is essential for restorative metabolic changes and its physiological correlates can be examined using overnight polysomnography. However, the association between physiological sleep characteristics and brain structure is not well understood. We aimed to investigate gray matter volume and cognitive performance related to physiological sleep characteristics. Methods Polysomnographic recordings from 190 community-dwelling participants were analyzed with a principal component analysis in order to identify and aggregate shared variance into principal components. The relationship between aggregated sleep components and gray matter volume was then analyzed using voxel-based morphometry. In addition, we explored how cognitive flexibility, selective attention, and semantic fluency were related to aggregated sleep components and gray matter volume. Results Three principal components were identified from the polysomnographic recordings. The first component, primarily described by apnea events and cortical arousal, was significantly associated with lower gray matter volume in the left frontal pole. This apnea-related component was furthermore associated with lower cognitive flexibility and lower selective attention. Conclusions Sleep disrupted by cortical arousal and breathing disturbances is paralleled by lower gray matter volume in the frontal pole, a proposed hub for the integration of cognitive processes. The observed effects provide new insights on the interplay between disrupted sleep, particularly breathing disturbances and arousal, and the brain.

Study objectives Periodic limb movements in sleep (PLMS) are frequent motor phenomena; however, population-based data are scarce. We assessed the prevalence of PLMS and factors associated with PLMS within two German population-based cohorts, the SHIP-TREND and BiDirect. Methods Single-night polysomnography was performed on 1107 subjects recruited from the general population (mean age: 52.9 years, 54.1% men) in the SHIP-TREND and on 247 participants (mean age: 57.6 years, 50.6% men) in the BiDirect. PLMS were evaluated using the standard criteria of the American Academy of Sleep Medicine. Sociodemographic data, behavioral variables, medical history, current medication, and other sleep disorders were assessed. Results The prevalence of PLMS index (PLMSI) >15/hour was 32.4% (SHIP-TREND) and 36.4% (BiDirect). In multivariable models, age (odds ratio [OR] = 1.05 per +1 year), male gender (OR = 2.20), restless legs syndrome (OR = 2.32), physical inactivity (OR = 1.52), current smoking (OR = 1.49), diabetes (OR = 2.13), antidepressant use (OR = 2.27), lower serum magnesium (OR per -0.1 mmol/L = 1.27) showed a positive, and the intake of beta-blockers an inverse association with PLMSI >15/hour in SHIP-TREND. In BiDirect, age (OR = 1.13 per +1 year), body mass index (OR = 1.11 per +1 kg/m2), and restless legs syndrome (OR = 8.77) were significantly associated with PLMSI >15/hour. Conclusions A high PLMSI is frequent in the German population. Age, male gender, restless legs syndrome, physical inactivity, current smoking, obesity, diabetes, antidepressant use, and lower magnesium were independently associated with PLMSI >15/hour in at least one of the cohorts.

The act of swallowing is a complex neuromuscular function that is processed in a distributed network involving cortical, subcortical and brainstem structures. Difficulty in swallowing arises from a variety of neurologic diseases for which therapeutic options are currently limited. Pharyngeal electrical stimulation (PES) is a novel intervention designed to promote plastic changes in the pharyngeal motor cortex to aid dysphagia rehabilitation. In the present study we evaluate the effect of PES on cortical swallowing network activity and associated changes in swallowing performance.In a randomized, crossover study design 10min of real (0.2-ms pulses, 5Hz, 280V, stimulation intensity at 75% of maximum tolerated threshold) or sham PES were delivered to 14 healthy volunteers in two separate sessions. Stimulation was delivered via a pair of bipolar ring electrodes mounted on an intraluminal catheter positioned in the pharynx. Before and after each intervention swallowing capacity (ml/s) was tested using a 150ml-water swallowing stress test. Event-related desynchronization (ERD) of cortical oscillatory activity during volitional swallowing was recorded applying whole-head magnetoencephalography before, immediately after and 45min past the intervention.A prominent reduction of ERD in sensorimotor brain areas occurred in the alpha and beta frequency ranges immediately after real PES but not after sham stimulation (p0.05) and had faded after 45min. Volume per swallow and swallowing capacity significantly increased following real stimulation only.Attenuation of ERD following PES reflects stimulation-induced increased swallowing processing efficiency, which is associated with subtle changes in swallowing function in healthy subjects. Our data contribute evidence that swallowing network organization and behavior can effectively be modulated by PES.

Decisions regarding tracheostomy tube removal after mechanical ventilation often depend on the physician's individual experience because evidence-based practice guidelines are still scarce, especially for critically ill neurologic patients. In these patients, the prevalence of aspiration is high and regarded as an important contributor to decannulation failure. The presence of severe neurological deficits may, however, give clinicians the subjective impression that a tracheostomy tube is still necessary although decannulation may actually be safe. It is therefore crucial to test swallowing function reliably prior to decannulation in this patient population.Prospective observational study.University hospital, neurological ICU.One hundred tracheostomized patients with acute neurologic disease completely weaned from mechanical ventilation.An endoscopic protocol evaluating readiness for decannulation and a conventional clinical swallowing examination were carried out by separate, experienced practitioners blinded to each other's decisions. Patient management always followed the decision made with endoscopy.Practitioners' decannulation decisions (yes/no) reached with both assessments were compared. Decannulated patients were monitored throughout their stay for complications related to tube removal. Endoscopy was performed successfully in all subjects without any complications. Following the protocol, the tracheostomy tube was successfully removed in 54 patients, whereas according to the clinical swallowing examination, only 29 patients would have been decannulated at that point. Only one patient needed recannulation due to respiratory problems, resulting in a failure rate of 1.9%.In neurologic patients, speech-language pathologists' impressions about the patient's state when clinically assessing indirect variables of swallowing function often lead to the unnecessary prolongation of cannulation time. Endoscopic evaluation has the advantage of objectively visualizing the patient's ability to manage secretions directly and allows for faster but, nonetheless, safe decannulation. The endoscopic protocol proposed here is a safe, efficient, and objective bedside tool to guide decannulation decisions.

The cortical organization of swallowing has been mainly studied in young and healthy subjects. Aging effects on human deglutition have been found in several behavioral studies and are known to affect both the oral and pharyngeal phases of swallowing. The aim of this study was to evaluate a potential cortical compensation of age-related swallowing impairment. Whole-head MEG was employed in 9 healthy elderly subjects (mean age 71.6 years) and compared to 9 healthy young participants (mean age 23.8 years). Data were analyzed by means of time-frequency plots and synthetic aperture magnetometry (SAM). Group analysis of individual SAM data was performed using a permutation test. The main finding of this study was an increase of somatosensory cortical activation during swallowing execution in elderly subjects compared to the young control group. This effect was present in both hemispheres. These results point to adaptive cerebral changes in response to aging effects on the complex process of swallowing. Our finding underlines the relevance of age matched control groups in neuroimaging studies related to deglutition or other complex sensorimotor processes.

BACKGROUND Kennedy disease (KD) clinically presents as progressive lower motor neuron disease with minimal or no sensory impairment. However, electrophysiological studies found abnormal somatosensory-evoked potentials even in absence of clinical deficits. Little is known about possible influences of this sensory neuropathy on the central somatosensory processing. METHODS In this study, the cortical topography of index finger representation was studied in 7 patients with genetically proven KD compared to healthy control subjects by means of magnetoencephalography using an established stimulation paradigm. Data analysis was carried out with synthetic aperture magnetometry (SAM). Additionally, the latency and source amplitude of the earliest cortical somatosensory-evoked field (SEF) component were determined based on traditional single dipole source analysis. RESULTS In KD patients the latency of the SEF was prolonged (48.6 vs. 37.4 ms, P < .005). There was no significant difference in dipole source amplitude, but stimulus-related SAM activation of the contralateral sensorimotor cortex (pseudo-t-values –.107 vs. –.199, P < .05), including maximum activity (53.5%), was reduced. CONCLUSIONS These results implicate that even subclinical sensory neuropathy leads to possible functional reorganization of the sensorimotor cortex in KD patients and reinforces the view that in KD the somatosensory system is extensively involved.

According to recent neuroimaging studies, swallowing is processed within multiple regions of the human brain. In contrast to this, little is known about the cortical contribution and compensatory mechanisms produced by impaired swallowing. In the present study, we therefore investigated the cortical topography of volitional swallowing in patients with X‐linked bulbospinal neuronopathy (Kennedy disease, KD). Eight dysphagic patients with genetically proven KD and an age‐matched healthy control group were studied by means of whole‐head magnetoencephalography using a previously established swallowing paradigm. Analysis of data was carried out with synthetic aperture magnetometry (SAM). The group analysis of individual SAM results was performed using a permutation test. KD patients showed significantly larger swallow‐related activation of the bilateral primary sensorimotor cortex than healthy controls. In contrast to the control group, in KD patients the maximum activity was located in the right sensorimotor cortex. Furthermore, while in nondysphagic subjects a previously described time‐dependent shift from the left to the right hemisphere was found during the one second of most pronounced swallow‐related muscle activity, KD patients showed a strong right hemispheric activation in each time segment analyzed. Since the right hemisphere has an established role in the coordination of the pharyngeal phase of swallowing, the stronger right hemispheric activation observed in KD patients indicates cortical compensation of pharyngeal phase dysphagia. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.

Background and Purpose— Fiberoptic endoscopic evaluation of swallowing (FEES) is an excellent method for the accurate examination of swallowing function in the acute phase of stroke. The present study investigates the safety of FEES related to patients characteristics in a setting of acute stroke care. Methods— A prospective study of FEES-associated complications was carried out in 300 acute stroke patients over a 1-year period. A neurologist and a speech-language pathologist of the stroke unit team performed FEES within a mean time interval of 1.9±0.8 days after stroke onset. A closely meshed monitoring of cardiovascular parameters was done during each examination. A discomfort rating was obtained from the patients. Results— In none of the 300 subjects any airway comprise, decrease in the level of consciousness, symptomatic bradycardia/tachycardia, laryngospasm, or epistaxis requiring special treatment was observed. The incidence of self-limiting nosebleeds was 6% and did not significantly differ in relation to major stroke types (ischemic versus hemorrhagic), acute treatment strategy (thrombolysis versus no thrombolysis), or secondary prevention regime (anticoagulant therapy versus antiplatelet drugs). Whereas no alterations in diastolic blood pressure were noted, statistically significant changes in systolic blood pressure, heart rate, and oxygen saturation occurred. However, these alterations did not cause any severe adverse event and were clinically judged as being mild. The assessment of comfort revealed an excellent tolerance of FEES in >80% of patients. Conclusion— This study demonstrates that FEES is a well-tolerated and safe method to assess swallowing function when performed by a speech-language pathologist and a neurologist in a stroke unit setting.

Dysphagia is a common symptom in myasthenia gravis (MG). Clinical examination alone fails to detect and grade myasthenic dysphagia sufficiently. For a more precise examination of swallowing function in myasthenia gravis additional technical tools are necessary. To investigate the diagnostic and therapeutic impact of fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application (FEES-Tensilon Test) in myasthenia gravis. FEES-Tensilon Test was performed following a standardized protocol. Four severely affected patients with dysphagia as their leading symptom were examined. Dysphagia was characterized by five salient endoscopic findings: leakage, delayed swallowing reflex, penetration, aspiration and residues. If a normalisation or at least an improvement of swallowing function occurred shortly after Tensilon administration the FEES-Tensilon Test was rated as being positive. In three patients the FEES-Tensilon Test successfully detected MG-related dysphagia. In one patient with dysphagia caused by oculopharyngeal muscular dystrophy the FEES-Tensilon Test was truly negative. Beside an early diagnosis of MG-related dysphagia, the FEES-Tensilon Test was useful in the differentiation between myasthenic and cholinergic crisis and in guiding treatment decisions. In all patients the FEES-Tensilon Test was superior to clinical evaluation of dysphagia. No severe side effect occurred while performing the FEES-Tensilon Test. The FEES-Tensilon Test is a suitable tool in the diagnosis and therapy of myasthenia gravis with pharyngeal muscles weakness.

Background: An increasing number of stroke patients have to be supported by mechanical ventilation in intensive care units (ICU), with a relevant proportion of them requiring gradual withdrawal from a respirator. To date, weaning studies have focused merely on mixed patient groups, COPD patients or patients after cardiac surgery. Therefore, the best weaning strategy for stroke patients remains to be determined. Methods: Here, we designed a prospective randomized controlled study comparing adaptive support ventilation (ASV), a continuous weaning strategy, with biphasic positive airway pressure (BIPAP) in combination with spontaneous breathing trials, a discontinuous technique, in the treatment of stroke patients. The primary endpoint was the duration of the weaning process. Results: Only the 40 (out of 54) patients failing in an initial spontaneous breathing trial (T-piece test) were included into the study; the failure proportion is considerably larger compared to previous studies. Eligible patients were pseudo-randomly assigned to one of the two weaning groups. Both groups did not differ regarding age, gender, and severity of stroke. The results showed that the median weaning duration was 10.7 days (±SD 7.0) in the discontinuous weaning group, and 8 days (±SD 4.5) in the continuous weaning group (p < 0.05). Conclusions: To the best of our knowledge, this is the first clinical study to show that continuous weaning is significantly more effective compared to discontinuous weaning in mechanically ventilated stroke patients. We suppose that the reason for the superiority of continuous weaning using ASV as well as the bad performance of our patients in the 2 h T-piece test is caused by the patients' compliance. Compared to patients on surgical and medical ICUs, neurological patients more often suffer from reduced vigilance, lack of adverse-effects reflexes, dysphagia, and cerebral dysfunction. Therefore, stroke patients may profit from a more gradual withdrawal of weaning.

OBJECTIVE: Current neuroimaging research on functional disturbances provides growing evidence for objective neuronal correlates of allegedly psychogenic symptoms, thereby shifting the disease concept from a psychological towards a neurobiological model. Functional dysphagia is such a rare condition, whose pathogenetic mechanism is largely unknown. In the absence of any organic reason for a patient's persistent swallowing complaints, sensorimotor processing abnormalities involving central neural pathways constitute a potential etiology. METHODS: In this pilot study we measured cortical swallow-related activation in 5 patients diagnosed with functional dysphagia and a matched group of healthy subjects applying magnetoencephalography. Source localization of cortical activation was done with synthetic aperture magnetometry. To test for significant differences in cortical swallowing processing between groups, a non-parametric permutation test was afterwards performed on individual source localization maps. RESULTS: Swallowing task performance was comparable between groups. In relation to control subjects, in whom activation was symmetrically distributed in rostro-medial parts of the sensorimotor cortices of both hemispheres, patients showed prominent activation of the right insula, dorsolateral prefrontal cortex and lateral premotor, motor as well as inferolateral parietal cortex. Furthermore, activation was markedly reduced in the left medial primary sensory cortex as well as right medial sensorimotor cortex and adjacent supplementary motor area (p

Swallowing is a complex neuromuscular task that is processed within multiple regions of the human brain. Rehabilitative treatment options for dysphagia due to neurological diseases are limited. Because the potential for adaptive cortical changes in compensation of disturbed swallowing is recognized, neuromodulation techniques like transcranial direct current stimulation (tDCS) are currently considered as a treatment option. Here we evaluate the effect of tDCS on cortical swallowing network activity and behavior. In a double-blind crossover study, anodal tDCS (20 min, 1 mA) or sham stimulation was administered over the left or right swallowing motor cortex in 21 healthy subjects in separate sessions. Cortical activation was measured using magnetoencephalography (MEG) before and after tDCS during cued "simple", "fast" and "challenged" swallow tasks with increasing levels of difficulty. Swallowing response times and accuracy were measured. Significant bilateral enhancement of cortical swallowing network activation was found in the theta frequency range after left tDCS in the fast swallow task (p=0.006) and following right tDCS in the challenged swallow task (p=0.007), but not after sham stimulation. No relevant behavioral effects were observed on swallow response time, but swallow precision improved after left tDCS (p

Sleep bruxism is assumed to be triggered by a dysfunctional subcortical and cortical network. This study investigates sensorimotor cortical activation in patients with sleep bruxism during clenching and chewing. Nine polysomnographically diagnosed patients and nine healthy control subjects underwent magnetoencephalography (MEG). During clenching and chewing, patients with bruxism revealed significantly larger event-related desynchronization in the somatomotor area (Brodmann area 4) than healthy subjects. Group differences in the muscle activity were ruled out by electromyography (EMG) assessments during MEG. This result might be regarded as a consequence of increased sensorimotor cortical representation of the tongue and chewing musculature due to an enhanced parafunctional muscle activity in bruxers potentially triggered by occlusal factors. Alternatively, a secondary activation of cortical structures during sleep bruxism in the context of an activated network of subcortical and cortical structures might lead to increased cortical representation of the chewing musculature via use dependent plasticity.

Amyotrophic lateral sclerosis (ALS) is a rare disease causing degeneration of the upper and lower motor neuron. Involvement of the bulbar motor neurons often results in fast progressive dysphagia. While cortical compensation of dysphagia has been previously shown in stroke patients, this topic has not been addressed in patients suffering from ALS. In the present study, we investigated cortical activation during deglutition in two groups of ALS patients with either moderate or severe dysphagia. Whole-head MEG was employed on fourteen patients with sporadic ALS using a self-paced swallowing paradigm. Data were analyzed by means of time-frequency analysis and synthetic aperture magnetometry (SAM). Group analysis of individual SAM data was performed using a permutation test. We found a reduction of cortical swallowing related activation in ALS patients compared to healthy controls. Additionally a disease-related shift of hemispheric lateralization was observed. While healthy subjects showed bilateral cortical activation, the right sensorimotor cortex was predominantly involved in ALS patients. Both effects were even stronger in the group of patients with severe dysphagia. Our results suggest that bilateral degeneration of the upper motor neuron in the primary motor areas also impairs further adjusted motor areas, which leads to a strong reduction of 'swallowing related' cortical activation. While both hemispheres are affected by the degeneration a relatively stronger activation is seen in the right hemisphere. This right hemispheric lateralization of volitional swallowing observed in this study may be the only sign of cortical plasticity in dysphagic ALS patients. It may demonstrate compensational mechanisms in the right hemisphere which is known to predominantly coordinate the pharyngeal phase of deglutition. These results add new aspects to our understanding of the pathophysiology of dysphagia in ALS patients and beyond. The compensational mechanisms observed could be relevant for future research in swallowing therapies.

Dysphagia is found in up to 80% of acute stroke patients. To date most studies have focused on ischemic stroke only. Little is known about the incidence and pattern of dysphagia in hemorrhagic stroke. Here we describe the characteristics of dysphagia in patients with striatocapsular hemorrhage. Fiberoptic Endoscopic Evaluation of Swallowing (FEES) was carried out in 30 patients with acute striatocapsular hemorrhage. Dysphagia was classified according to the six-point Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS) within 72 h after admission. Lesion volume, hemisphere and occurrence of ventricular rupture were determined from computer tomography scans. Data on initial NIH-SS, clinical symptoms, need for endotracheal intubation, diagnosis of pneumonia and feeding status on discharge were recorded. Swallowing impairment was observed in 76.7% of patients (n = 23). Mean FEDSS score was 3.1 ± 1.5. Main findings were penetration or aspiration of liquids as well as leakage to valleculae and piriform sinus. Incidence of pneumonia was 30.0% (n = 9). Age, NIH-SS and hematoma volume did not correlate with dysphagia severity. None of the clinical characteristics was predictive for dysphagia. On discharge after 12.9 ± 5.3 days, a two-point improvement on the FEDSS was seen in seven patients, (30.4%) and five patients (21.7%) had gained at least one point. In striatocapsular hemorrhage, dysphagia is a common and so far underrecognized symptom. FEES results indicate predominant impairment of oral motor control. Swallowing impairment is not related to other clinical deficits, stroke severity or lesion characteristics. Thus, detailed dysphagia assessment is indicated in all cases.

Dysphagia is a frequent and early symptom in progressive supranuclear palsy (PSP) predisposing patients to aspiration pneumonia. Fiberoptic endoscopic evaluation of swallowing (FEES®) has emerged as a valuable apparative tool for objective evaluation of neurogenic dysphagia. This is the first study using FEES® to investigate the nature of swallowing impairment in PSP. Eighteen consecutive PSP patients (mean age 69.7 ± 9.0 years) were included. The salient findings of FEES® in PSP patients were compared with those of 15 patients with Parkinson's disease (PD). In 7 PSP patients, a standardized FEES® protocol was performed to explore levodopa (L-dopa) responsiveness of dysphagia. Most frequent abnormalities detected by FEES® were bolus leakage, delayed swallowing reflex, and residues in valleculae and piriformes. Aspiration events with at least one food consistency occurred in nearly 30% of PSP patients. Significant pharyngeal saliva pooling was observed in 4 PSP patients. We found no difference of salient endoscopic findings between PSP and PD patients. Endoscopic dysphagia severity in PSP correlated positively with disease duration, clinical disability, and cognitive impairment. No correlation was found with dysarthria severity. In early PSP patients, swallowing dysfunction was solely characterized by liquid leakage with the risk of predeglutitive aspiration during the oral phase of swallowing. Two PSP patients showed relevant improvement of swallowing function after L-dopa challenge. Chin tuck—maneuver, hard swallow, and modification of food consistency were identified as the most effective therapeutic interventions. In conclusion, FEES® assessment can deliver important findings for the diagnosis and refined therapy of dysphagia in PSP patients. © 2010 Movement Disorder Society

Hereditary amyloidosis of the Finnish type (HAF, or familial amyloid polyneuropathy type IV) is an autosomal dominant disease that has been described most commonly in the Finnish population but has also been found in some other countries. Herein we report the first German family whose members suffer from this condition. There are no known Finnish ancestors. We performed clinical and electrophysiological examinations in 22 members of this family. All symptomatic family members suffered from facial palsy, and most of them had peripheral neuropathy. One patient had confirmed corneal lattice dystrophy. Additional symptoms were hypoglossal nerve involvement in 5 patients and oculomotor nerve palsy in 1 patient. The lips of all older patients appeared thickened. The causative G654A mutation in the gelsolin gene was found in all affected family members.

Background Impaired speech perception is one of the major sequelae of aging. In addition to peripheral hearing loss, central deficits of auditory processing are supposed to contribute to the deterioration of speech perception in older individuals. To test the hypothesis that auditory temporal processing is compromised in aging, auditory evoked magnetic fields were recorded during stimulation with sequences of 4 rapidly recurring speech sounds in 28 healthy individuals aged 20 – 78 years. Results The decrement of the N1m amplitude during rapid auditory stimulation was not significantly different between older and younger adults. The amplitudes of the middle-latency P1m wave and of the long-latency N1m, however, were significantly larger in older than in younger participants. Conclusion The results of the present study do not provide evidence for the hypothesis that auditory temporal processing, as measured by the decrement (short-term habituation) of the major auditory evoked component, the N1m wave, is impaired in aging. The differences between these magnetoencephalographic findings and previously published behavioral data might be explained by differences in the experimental setting between the present study and previous behavioral studies, in terms of speech rate, attention, and masking noise. Significantly larger amplitudes of the P1m and N1m waves suggest that the cortical processing of individual sounds differs between younger and older individuals. This result adds to the growing evidence that brain functions, such as sensory processing, motor control and cognitive processing, can change during healthy aging, presumably due to experience-dependent neuroplastic mechanisms.

Dysphagia in X-linked bulbospinal muscular atrophy (Kennedy disease) has never been characterized in detail by objective swallowing studies. We assessed the nature of swallowing impairment in Kennedy disease by undertaking fiberoptic endoscopic evaluation of swallowing examinations of 10 genetically confirmed patients with Kennedy disease who were scored according to an ordinal rating scale including 25 different items. The results were compared to an age-matched control group of 10 healthy volunteers. Swallowing dysfunction was found in 80% of patients with Kennedy disease. The main pattern of dysphagia was an incomplete food bolus clearance through the pharynx with residues left in the valleculae overflowing into the laryngeal vestibule after the swallow. Total duration of the pharyngeal swallow was significantly shorter in patients with Kennedy disease compared to the control group. These findings suggest that dysphagia in Kennedy disease is predominantly characterized by an impairment of the pharyngeal phase of swallowing resulting from reduced base-of-tongue movement and bilateral paresis of pharyngeal and laryngeal muscles.

Background and Purpose: Fiberoptic endoscopic evaluation of swallowing (FEES) is a suitable method for dysphagia assessment after acute stroke. Recently, we developed the fiberoptic endoscopic dysphagia severity scale (FEDSS) for acute stroke patients, grading dysphagia into 6 severity codes (1 to 6; 1 being best). The purpose of this study was to investigate the impact of the FEDSS as a predictor of outcomes at 3 months and intermediate complications during acute treatment. Methods: A total of 153 consecutive first-ever acute stroke patients were enrolled. Dysphagia was classified according to the FEDSS, assessed within 24 h after admission. Intermediate outcomes were pneumonia and endotracheal intubation. Functional outcome was measured by the modified Rankin Scale (mRS) at 3 months. Multivariate regression analysis was used to identify whether the FEDSS was an independent predictor of outcome and intercurrent complications. Analyses were adjusted for sex, age and National Institutes of Health Stroke Scale (NIH-SS) on admission. Results: The FEDSS was found to predict the mRS at 3 months as well as but independent from the NIH-SS. For each additional point on the FEDSS, the likelihood of dependency at 3 months (mRS ≥ 3) raised by ∼50%. Each increase of 1 point on the FEDSS conferred a more than 2-fold increased chance of developing pneumonia. The odds for the necessity of endotracheal intubation raised by a factor of nearly 2.5 with each additional point on the FEDSS. Conclusions: The FEDSS strongly and independently predicts outcome and intercurrent complications after acute stroke. Thus, a baseline FEES examination provides valuable prognostic information for the treatment of acute stroke patients.

Background Botulism is a rare disease caused by intoxication leading to muscle weakness and rapidly progressive dysphagia. With adequate therapy signs of recovery can be observed within several days. In the last few years, brain imaging studies carried out in healthy subjects showed activation of the sensorimotor cortex and the insula during volitional swallowing. However, little is known about cortical changes and compensation mechanisms accompanying swallowing pathology. Methods In this study, we applied whole-head magnetoencephalography (MEG) in order to study changes in cortical activation in a 27-year-old patient suffering from wound botulism during recovery from dysphagia. An age-matched group of healthy subjects served as control group. A self-paced swallowing paradigm was performed and data were analyzed using synthetic aperture magnetometry (SAM). Results The first MEG measurement, carried out when the patient still demonstrated severe dysphagia, revealed strongly decreased activation of the somatosensory cortex but a strong activation of the right insula and marked recruitment of the left posterior parietal cortex (PPC). In the second measurement performed five days later after clinical recovery from dysphagia we found a decreased activation in these two areas and a bilateral cortical activation of the primary and secondary sensorimotor cortex comparable to the results seen in a healthy control group. Conclusion These findings indicate parallel development to normalization of swallowing related cortical activation and clinical recovery from dysphagia and highlight the importance of the insula and the PPC for the central coordination of swallowing. The results suggest that MEG examination of swallowing can reflect short-term changes in patients suffering from neurogenic dysphagia.

Background and Purpose: Dysphagia is an important complication of acute stroke with a reported incidence of up to 76%. The purpose of this investigation was to develop and to evaluate an endoscopic scoring system which has the potential to guide dysphagia management in acute stroke patients. Methods: A fiberoptic endoscopic evaluation of swallowing (FEES) was carried out in 100 patients within 72 h of stroke onset. During endoscopic examination, the secretion status was evaluated, and the patient was successively given standard volumes of puree consistency, liquids and soft solid food. Penetration and aspiration was assessed using a 5-point scale. Results: Nearly 80% of patients showed penetration or aspiration during FEES. These events occurred more frequently with liquids and soft solid food than with puree. Penetration or aspiration at any stage of examination predicted failure at the subsequent food consistency. Furthermore, key findings of endoscopic evaluation were predictive of the need for later orotracheal intubation. Based on these observations a score was developed that grades stroke-related dysphagia according to the risk of penetration or aspiration of the different food consistencies tested. Assessment of interrater reliability by means of 25 additional endoscopic examinations resulted in excellent agreement between three investigators, reflected by a ĸ coefficient of 0.89. Conclusion: Stroke-related dysphagia may effectively be graded using a simple endoscopic scoring system. The usefulness of this screening protocol with respect to patient outcome and intercurrent complications has to be studied in prospective clinical trials.

Synthetic aperture magnetometry (SAM) is a powerful MEG source localization method to analyze evoked as well as induced brain activity. To gain structural information of the underlying sources, especially in group studies, individual magnetic resonance images (MRI) are required for co-registration. During the last few years, the relevance of MEG measurements on understanding the pathophysiology of different diseases has noticeable increased. Unfortunately, especially in patients and small children, structural MRI scans cannot always be performed. Therefore, we developed a new method for group analysis of SAM results without requiring structural MRI data that derives its geometrical information from the individual volume conductor model constructed for the SAM analysis. The normalization procedure is fast, easy to implement and integrates seamlessly into an existing landmark based MEG-MRI co-registration procedure. This new method was evaluated on different simulated points as well as on a pneumatic index finger stimulation paradigm analyzed with SAM. Compared with an established MRI-based normalization procedure (SPM2) the new method shows only minor errors in single subject results as well as in group analysis. The mean difference between the two methods was about 4 mm for the simulated as well as for finger stimulation data. The variation between individual subjects was generally higher than the error induced by the missing MRIs. The method presented here is therefore sufficient for most MEG group studies. It allows accomplishing MEG studies with subject groups where MRI measurements cannot be performed.

Background Sensory input is crucial to the initiation and modulation of swallowing. From a clinical point of view, oropharyngeal sensory deficits have been shown to be an important cause of dysphagia and aspiration in stroke patients. In the present study we therefore investigated effects of functional oropharyngeal disruption on the cortical control of swallowing. We employed whole-head MEG to study cortical activity during self-paced volitional swallowing with and without topical oropharyngeal anesthesia in ten healthy subjects. A simple swallowing screening-test confirmed that anesthesia caused swallowing difficulties with decreased swallowing speed and reduced volume per swallow in all subjects investigated. Data were analyzed by means of synthetic aperture magnetometry (SAM) and the group analysis of the individual SAM data was performed using a permutation test. Results The analysis of normal swallowing revealed bilateral activation of the mid-lateral primary sensorimotor cortex. Oropharyngeal anesthesia led to a pronounced decrease of both sensory and motor activation. Conclusion Our results suggest that a short-term decrease in oropharyngeal sensory input impedes the cortical control of swallowing. Apart from diminished sensory activity, a reduced activation of the primary motor cortex was found. These findings facilitate our understanding of the pathophysiology of dysphagia.

We used magnetoencephalography to study contralesional auditory reorganization in three men with chronic unilateral ischemic lesions of the auditory cortex. Although no response was found over the lesioned hemisphere, processing in the unaffected hemisphere was indistinguishable vs healthy controls. In contrast to sensorimotor and language systems, the auditory system seems to lack contralateral reorganization, presumably because patients are typically not aware of hearing deficits and thus do not perform training.

Activation of the auditory cortex habituates with repeated stimulation. While behaviorally adaptive in most circumstances, decreasing auditory responsiveness could interfere with speech perception. We therefore tested whether auditory habituation differs for speech and non-speech stimuli and for left and right auditory cortex. We examined seven right-handed subjects in whom we had determined left-hemispheric language dominance by event-related blood flow assessment. We recorded magnetoencephalographic-evoked responses to trains of four sine tones or vowels and measured the decrement from the first to the last stimulus of the response component about 100 ms after stimulus onset (N1). For the sine tones there was a decrement in both hemispheres. Conversely, for vowels there was significant attenuation of the auditory decrement in the left compared with the right hemisphere (p=0.017). This left-hemisphere persistence in auditory responsiveness to vowels demonstrates that the human brain processes speech stimuli differently than non-speech stimuli and that the left-hemisphere plays a dominant role in this speech-specific auditory processing.

Background Dysphagia is common after stroke. Fiberoptic endoscopic evaluation of swallowing (FEES) is a powerful tool for dysphagia assessment. The purpose of this study was to assess whether a previously established endoscopic examination protocol based on the identification of typical findings indicative of stroke – related dysphagia may be learned and adopted by clinicians so far inexperienced in this field. Methods After receiving a structured lecture on this topic, participants were asked to rate video sequences of endoscopic swallowing examinations of acute stroke patients. The first part of the testing ("single findings-rating") comprised of 16 single sequences, the second part ("complete examination-rating") presented the key sequences of 8 complete examinations. Before the second part was started, results of the first were discussed. Results At the "single findings-rating" 88.8% of video-sequences were assessed correctly, while at the "complete examination-rating" the average performance had improved to 96%. Furthermore, no overlooking of relevant pathologies was noted in the second part of the testing. Conclusion This study suggests that the presented endoscopic examination protocol is reliably interpreted by inexperienced clinicians after a short lecture and may therefore easily and successfully be adopted in dysphagia management of acute stroke care.

Background Dysphagia is a leading complication in stroke patients causing aspiration pneumonia, malnutrition and increased mortality. Current strategies of swallowing therapy involve on the one hand modification of eating behaviour or swallowing technique and on the other hand facilitation of swallowing with the use of pharyngeal sensory stimulation. Thermal tactile oral stimulation (TTOS) is an established method to treat patients with neurogenic dysphagia especially if caused by sensory deficits. Little is known about the possible mechanisms by which this interventional therapy may work. We employed whole-head MEG to study changes in cortical activation during self-paced volitional swallowing in fifteen healthy subjects with and without TTOS. Data were analyzed by means of synthetic aperture magnetometry (SAM) and the group analysis of individual SAM data was performed using a permutation test. Results Compared to the normal swallowing task a significantly increased bilateral cortical activation was seen after oropharyngeal stimulation. Analysis of the chronological changes during swallowing suggests facilitation of both the oral and the pharyngeal phase of deglutition. Conclusion In the present study functional cortical changes elicited by oral sensory stimulation could be demonstrated. We suggest that these results reflect short-term cortical plasticity of sensory swallowing areas. These findings facilitate our understanding of the role of cortical reorganization in dysphagia treatment and recovery.