Levodopa responsiveness of dysphagia in advanced Parkinson's disease and reliability testing of the FEES-Levodopa-test.

BACKGROUND: It is still controversially discussed whether central dopaminergic stimulation improves swallowing ability in Parkinson's disease (PD). We evaluated the effect of oral levodopa application on dysphagia in advanced PD patients with motor fluctuations. METHODS: In 15 PD patients (mean age 71.93 ± 8.29 years, mean disease duration 14.33 ± 5.94 years) with oropharyngeal dysphagia and motor fluctuations endoscopic swallowing evaluation was performed in the off state and on state condition following a specifically developed protocol (FEES-levodopa-test). The respective dysphagia score covered three salient parameters, i. e. premature spillage, penetration/aspiration events and residues, each tested with liquid as well as semisolid and solid food consistencies. An improvement of >30% in this score indicated levodopa responsiveness of dysphagia. Measures were compared between the off- and on-state condition by using the Wilcoxon Test and marginal homogeneity test. Inter- and intrarater reliability was also investigated. RESULTS: Severity of swallowing dysfunction in the off state varied widely. The lowest dysphagia score was 15 points (dysphagia without any aspiration risk). The highest dysphagia score was 84 points (dysphagia with aspiration of all consistencies). Seven patients showed a marked improvement of dysphagia in the on state condition. Eight PD patients did not respond. Inter- and intrarater reliability was excellent for all three subscales in the off state and on state conditions. CONCLUSIONS: A significant proportion of advanced PD patients with motor fluctuations and mild to moderate oropharyngeal dysphagia may demonstrate a clinically relevant improvement of swallowing after levodopa challenge. The FEES-levodopa-test is a reliable and sensitive tool to differentiate these responders from non-responders.

Electrical pharyngeal stimulation for dysphagia treatment in tracheotomized stroke patients: a randomized controlled trial.

PURPOSE: Treatment of post-stroke dysphagia is notoriously difficult with different neurostimulation strategies having been employed with a variable degree of success. Recently, electrical pharyngeal stimulation (EPS) has been shown to improve swallowing function and in particular decrease airway aspiration in acute stroke. We performed a randomized controlled trial to assess EPS effectiveness on swallowing function in severely dysphagic tracheotomized patients. METHODS: All consecutive stroke patients successfully weaned from the respirator but with severe dysphagia precluding decannulation were screened for eligibility. Eligible patients were randomized to receive either EPS (N = 20) or sham stimulation (N = 10) over three consecutive days. Primary endpoint was ability to decannulate the patient. Swallowing function was assessed using fiberoptic endoscopy. Patients having received sham stimulation were offered EPS treatment during unblinded follow-up if required. Investigators were blinded to the patient's study group allocation. RESULTS: Both groups were well matched for age, stroke severity, and lesion location. Decannulation after study intervention was possible in 75% of patients of the treatment group and in 20% of patients of the sham group (p < 0.01). Secondary outcome parameters did not differ. No adverse events occurred. CONCLUSION: In this pilot study, EPS enhanced remission of dysphagia as assessed with fiberoptic endoscopic evaluation of swallowing (FEES), thereby enabling decannulation in 75% of patients.

Pharyngeal electrical stimulation can modulate swallowing in cortical processing and behavior - magnetoencephalographic evidence.

BACKGROUND: 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. METHODS: 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. RESULTS: 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 (p<0.05) and had faded after 45min. Volume per swallow and swallowing capacity significantly increased following real stimulation only. CONCLUSION: 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.

Altered cortical swallowing processing in patients with functional dysphagia: a preliminary study.

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<0.01). CONCLUSIONS: Functional dysphagia--a condition with assumed normal brain function--seems to be associated with distinctive changes of the swallow-related cortical activation pattern. Alterations may reflect exaggerated activation of a widely distributed vigilance, self-monitoring and salience rating network that interferes with down-stream deglutition sensorimotor control.

Standardized endoscopic swallowing evaluation for tracheostomy decannulation in critically ill neurologic patients.

OBJECTIVES: 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. DESIGN: Prospective observational study. SETTING: University hospital, neurological ICU. PATIENTS: One hundred tracheostomized patients with acute neurologic disease completely weaned from mechanical ventilation. INTERVENTIONS: 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. MEASUREMENTS AND MAIN RESULTS: 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%. CONCLUSIONS: 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.

Magnetoencephalographic evidence for the modulation of cortical swallowing processing by transcranial direct current stimulation.

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<0.05). Anodal tDCS applied over the swallowing motor cortex of either hemisphere was able to increase bilateral swallow-related cortical network activation in a frequency specific manner. These neuroplastic effects were associated with subtle behavioral gains during complex swallow tasks in healthy individuals suggesting that tDCS deserves further evaluation as a treatment tool for dysphagia.

Evidence for adaptive cortical changes in swallowing in Parkinson's disease.

Dysphagia is a relevant symptom in Parkinson's disease, whose pathophysiology is poorly understood. It is mainly attributed to degeneration of brainstem nuclei. However, alterations in the cortical contribution to deglutition control in the course of Parkinson's disease have not been investigated. Here, we sought to determine the patterns of cortical swallowing processing in patients with Parkinson's disease with and without dysphagia. Swallowing function in patients was objectively assessed with fiberoptic endoscopic evaluation. Swallow-related cortical activation was measured using whole-head magnetoencephalography in 10 dysphagic and 10 non-dysphagic patients with Parkinson's disease and a healthy control group during self-paced swallowing. Data were analysed applying synthetic aperture magnetometry, and group analyses were done using a permutation test. Compared with healthy subjects, a strong decrease of cortical swallowing activation was found in all patients. It was most prominent in participants with manifest dysphagia. Non-dysphagic patients with Parkinson's disease showed a pronounced shift of peak activation towards lateral parts of the premotor, motor and inferolateral parietal cortex with reduced activation of the supplementary motor area. This pattern was not found in dysphagic patients with Parkinson's disease. We conclude that in Parkinson's disease, not only brainstem and basal ganglia circuits, but also cortical areas modulate swallowing function in a clinically relevant way. Our results point towards adaptive cerebral changes in swallowing to compensate for deficient motor pathways. Recruitment of better preserved parallel motor loops driven by sensory afferent input seems to maintain swallowing function until progressing neurodegeneration exceeds beyond the means of this adaptive strategy, resulting in manifestation of dysphagia.

Septic cavernous sinus thrombosis complicated by occlusion of the internal carotid artery and multiple embolic strokes after surgery of an anorectal abscess: a clinical chameleon.

BACKGROUND: Septic thrombosis of the cavernous sinus (CST) is a rare and potentially life-threatening condition mostly caused by facial or ear, nose, and throat infections. Anatomic structures in vicinity of the cavernous sinus are thereby susceptible to inflammatory damage. In particular nervous system structures are almost regularly affected; however, only few authors reported severe involvement of the internal carotid artery (ICA). CASE PRESENTATION: We present an atypical clinical course of CST in a 61-year-old male diabetic patient caused by a distant focus of inflammation. Septic CST after surgical treatment of an anorectal abscess was complicated by occlusion of the ICA and multiple embolic strokes. The diagnosis was established by magnetic resonance imaging scan, symptoms resolved after antibiotic therapy and heparin anticoagulation. CONCLUSIONS: The presented case and review of literature emphasizes the variability of signs and clinical course of CST, a frequent cause of delayed diagnosis. Especially in immunocompromised patients, the primary source of CST may be a distant inflammatory focus with nonspecific and subacute symptoms. Septic CST can be a rare cause of ischemic stroke when complicated by ICA occlusion because of septic arteritis. Expedited diagnostic workup is necessary and rests upon radiologic investigations.

Dysphagia in patients with acute striatocapsular hemorrhage.

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.

Cortical processing of swallowing in ALS patients with progressive dysphagia--a magnetoencephalographic study.

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.

Intravenous lacosamide--an effective add-on treatment of refractory status epilepticus.

Status epilepticus (SE) is a frequent neurological emergency requiring immediate treatment. Therapy usually requires intravenous anticonvulsive medication. Lacosamide is a novel anticonvulsant drug that is available as infusion solution. We describe seven patients with focal SE who were treated with intravenous Lacosamide. All patients in our case series were unsuccessfully treated with other antiepileptic drugs before Lacosamide i.v. was added. In all cases, SE was terminated within 24 h after Lacosamide. There were no serious side effects or adverse events attributable to Lacosamide i.v. Our data suggest that Lacosamide might be an effective add-on treatment, if standard drugs fail or are unsuitable.

Cortical swallowing processing in early subacute stroke.

BACKGROUND: Dysphagia is a major complication in hemispheric as well as brainstem stroke patients causing aspiration pneumonia and increased mortality. Little is known about the recovery from dysphagia after stroke. The aim of the present study was to determine the different patterns of cortical swallowing processing in patients with hemispheric and brainstem stroke with and without dysphagia in the early subacute phase. METHODS: We measured brain activity by mean of whole-head MEG in 37 patients with different stroke localisation 8.2+/-4.8 days after stroke to study changes in cortical activation during self-paced swallowing. An age matched group of healthy subjects served as controls. Data were analyzed by means of synthetic aperture magnetometry and group analyses were performed using a permutation test. RESULTS: Our results demonstrate strong bilateral reduction of cortical swallowing activation in dysphagic patients with hemispheric stroke. In hemispheric stroke without dysphagia, bilateral activation was found. In the small group of patients with brainstem stroke we observed a reduction of cortical activation and a right hemispheric lateralization. CONCLUSION: Bulbar central pattern generators coordinate the pharyngeal swallowing phase. The observed right hemispheric lateralization in brainstem stroke can therefore be interpreted as acute cortical compensation of subcortically caused dysphagia. The reduction of activation in brainstem stroke patients and dysphagic patients with cortical stroke could be explained in terms of diaschisis.

Decreased cortical somatosensory finger representation in X-linked recessive bulbospinal neuronopathy (Kennedy disease): a magnetoencephalographic study.

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.

Dysphagia in X-linked bulbospinal muscular atrophy (Kennedy disease).

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.

Tactile thermal oral stimulation increases the cortical representation of swallowing.

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.

Cortical compensation associated with dysphagia caused by selective degeneration of bulbar motor neurons.

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.

Functional oropharyngeal sensory disruption interferes with the cortical control of swallowing.

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.