Dysphagic Stroke Patients Research Articles

A comparison of percutaneous endoscopic gastrostomy and nasogastric tube feeding in prolonged dysphagic stroke patients

Objective To evaluate the effectiveness and the safety of percutaneous endoscopic gastrostomy (PEG) as compared with a nasogastric (NG) tube for adults with prolonged neurological dysphagia after stroke. Design A prospective case-controlled study. Patients and methods This study included 90 patients with severe neurogenic dysphagia categorized into two groups: those on PEG feeding and those on NG feeding because they refused PEG. A comparison of both groups was assessed by several methods. The primary outcome measures were death and aspiration pneumonia during 3 months' observation and the 2ry outcome measures were changes in the nutritional state during this period and patient and family satisfaction. Results Weight gain was significantly higher among patients in the NG group. The incidence of aspiration pneumonia was significantly higher among patients in the NG group (14) compared with seven patients in PEG. There were four (8.3%) deaths in the PEG group compared with eight (18.2%) in the NG group. Conclusion This study has demonstrated that PEG feeding in long-term dysphagic patients with stroke is associated with a significant reduction in the incidence of aspiration pneumonia with reduced mortality at 3 months. PEG is more acceptable and less irritating to patients and is superior in the delivery of feed and maintaining the nutritional status and improves the long-term quality of life.

Considerations for medication in dysphagic stroke patients

Dysphagia is a significant problem associated with stroke, which can cause many complications relating to nutrition and hydration, as well as a person's ability to take medication. This article provides a brief overview of stroke and dysphagia, and discusses problems likely to be encountered in administering medication to patients following a stroke. It suggests methods of ensuring the best quality of service to these patients, and outlines drugs used in stroke treatment. Aspects of interdisciplinary dysphagia management after stroke noted by McFarlane et al (2014) are expanded on.

Dysphagia Evaluation by Using Cross-correlation Coefficient of Bilateral Submental Muscles' Surface Electromyography

To investigate the swallowing discoordination of bilateral submental muscles in dysphagic stroke patients by analyzing the surface electromyography (sEMG) and to compare to those of the healthy subjects.

OC-065 Functional Cortical Swallowing Activity And Neurotransmitters Concentrations Are Altered Following Neurostimulation Of Pharyngeal Motor Cortex: An Fmri And Resonance Spectroscopy (mrs) Study

IntroductionCombined pharyngeal electrical and transcranial-magnetic-stimulation or paired associative stimulation (PAS) is shown to induce beneficial neurophysiological and behavioural effects on swallowing in health and dysphagic stroke patients (Michou et al.,...

Is stroke rehabilitation a metabolic problem?

Background: This study looks at the impact of inflammation during the rehabilitation stage of strokes and its effect on neuro-functional recovery.Methods: This study investigated 94 patients suffering from strokes and admitted to rehabilitation. Anthropometric characteristics, serum proteins and inflammatory markers, plasma amino acids and neurofunction were all assessed.Results: 55.3% patients had an inflammatory status (Interleukin-6 = 19.24 ± 23.01 pg ml−1 vs. 4.1 ± 1.6 pg ml−1 for non-inflamed subjects (p < 0.001). Inflammation was positively linked to positive proteins (alpha-1 globulin, p < 0.02) and negatively linked to negative proteins (albumin, p < 0.02; prealbumin, p < 0.01; transferrin, p < 0.05) of the acute-phase response. Inflammation was associated with low plasma concentrations of total amino acids. For the multiple logistic regression analysis, albumin (p < 0.001) and body weight maintenance (p < 0.001) were independent predictors of patient functional independence. Inflammation in dysphagic stroke (31.9%) patients was associated with more accentuated disability compared to non-inflamed dysphagics. The serum positive reactant alpha 1 globulin was the most powerful predictor of dysphagia severity (p < 0.001). At discharge, dysphagia improvement was associated with improved acute-phase negative proteins.Conclusions: An inflammatory status may persist for most patients with strokes during the rehabiliation stage of the disease, its prevalence being higher in dysphagic compared to non-dysphagic subjects. The improvement in circulating albumin and body weight maintenance are predictors of neuro-function, even in dysphagic subjects.

The effect of early neuromuscular electrical stimulation therapy in acute/subacute ischemic stroke patients with Dysphagia.

ObjectiveTo compare the outcome of an early application of neuromuscular electrical stimulation (NMES) combined with traditional dysphagia therapy (TDT) versus traditional dysphagia therapy only in acute/subacute ischemic stroke patients with moderate to severe dysphagia by videofluoroscopic swallowing study (VFSS).MethodsFifty-seven dysphagic stroke patients were enrolled in a VFSS within 10 days after stroke onset. Patients were randomly assigned into two treatment groups. Thirty-one patients received NMES combined with TDT (NMES/TDT group) and 26 patients received TDT only (TDT group). Electrical stimulation with a maximal tolerable intensity was applied on both suprahyoid muscles for 30 minutes, 5 days per week during 3 weeks. The swallowing function was evaluated at baseline and 3, 6, and 12 weeks after baseline. Outcomes of the VFSS were assessed using the Functional Oral Intake Scale (FOIS).ResultsThe mean ages were 63.5±11.4 years in the NMES/TDT group and 66.7±9.5 years in the TDT group. Both groups showed a significant improvement on the FOIS after treatment. The FOIS score was significantly more improved at 3 and 6 weeks after baseline in the NMES/TDT group than in the TDT group (p<0.05).ConclusionAn early application of NMES combined with TDT showed a positive effect in acute/subacute ischemic stroke patients with dysphagia. These results indicated that the early application of NMES could be used as a supplementary treatment of TDT to help rehabilitate acute/subacute dysphagic stroke patients by improving their swallowing coordination.

Pharyngeal Stimulation in Head and Neck Cancer Patients with Dysphagia: Functional Outcomes and Transcranial Magnetic Stimulation Motor Evoked Potentials

Purpose: Head and neck cancer patients often experience swallowing disorders, impacting health and quality of life. This study examined effects of electrical stimulation to the pharynx on swallowing outcomes in post-surgical head and neck cancer patients. Methods: Swallowing was assessed using video fluoroscopy before, and 30 minutes after, a ten-minute application of electrical stimulation to the pharynx in five patients experiencing moderate-severe dysphagia. Corticopharyngeal motor projections were measured before and after stimulation of the pharynx using transcranial magnetic stimulation of motor cortex and measurements of motor evoked potentials (MEPs) in the striated muscle of the posterior pharyngeal wall. Results: Short-term changes in swallowing function were observed post-stimulation in: pharyngeal transit time, cricopharyngeal opening duration, total number of swallows, penetration/aspiration score, and duration of contact between the base of tongue and posterior pharyngeal wall. MEPs could not be measured in two participants. In the remaining participants, the MEP measures were not strongly associated with changes in observed swallowing function as has been found for neurogenic dysphagia. Conclusions: These findings indicated that somatosensory input, generated by electrical stimulation of the pharynx, changes swallowing function in head and neck cancer patients. These changes are not strongly correlated with alterations of corticopharyngeal excitability as previously observed in acutely dysphagic stroke patients.

Effect of Low-Frequency rTMS and NMES on Subacute Unilateral Hemispheric Stroke With Dysphagia

ObjectiveTo investigate the effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) and neuromuscular electrical stimulation (NMES) on post-stroke dysphagia.MethodsSubacute (<3 months), unilateral hemispheric stroke patients with dysphagia were randomly assigned to the conventional dysphagia therapy (CDT), rTMS, or NMES groups. In rTMS group, rTMS was performed at 100% resting motor threshold with 1 Hz frequency for 20 minutes per session (5 days per week for 2 weeks). In NMES group, electrical stimulation was applied to the anterior neck for 30 minutes per session (5 days per week for 2 weeks). All three groups were given conventional dysphagia therapy for 4 weeks. We evaluated the functional dysphagia scale (FDS), pharyngeal transit time (PTT), the penetration-aspiration scale (PAS), and the American Speech-Language Hearing Association National Outcomes Measurement System (ASHA NOMS) swallowing scale at baseline, after 2 weeks, and after 4 weeks.ResultsForty-seven patients completed the study; 15 in the CDT group, 14 in the rTMS group, and 18 in the NMES group. Mean changes in FDS and PAS for liquid during first 2 weeks in the rTMS and NMES groups were significantly higher than those in the CDT group, but no significant differences were found between the rTMS and NMES group. No significant difference in mean changes of FDS and PAS for semi-solid, PTT, and ASHA NOMS was observed among the three groups.ConclusionThese results indicated that both low-frequency rTMS and NMES could induce early recovery from dysphagia; therefore, they both could be useful therapeutic options for dysphagic stroke patients.

Characterizing the Mechanisms of Central and Peripheral Forms of Neurostimulation in Chronic Dysphagic Stroke Patients

BackgroundSwallowing problems following stroke may result in increased risk of aspiration pneumonia, malnutrition, and dehydration. Objective/hypothesisOur hypothesis was that three neurostimulation techniques would produce beneficial effects on chronic dysphagia following stroke through a common brain mechanism that would predict behavioral response. MethodsIn 18 dysphagic stroke patients (mean age: 66 ± 3 years, 3 female, time-post-stroke: 63 ± 15 weeks [±SD]), pharyngeal electromyographic responses were recorded after single-pulse transcranial magnetic stimulation (TMS) over the pharyngeal motor cortex, to measure corticobulbar excitability before, immediately, and 30 min, after real and sham applications of neurostimulation. Patients were randomized to a single session of either: pharyngeal electrical stimulation (PES), paired associative stimulation (PAS) or repetitive TMS (rTMS). Penetration-aspiration scores and bolus transfer timings were assessed before and after both real and sham interventions using videofluoroscopy. ResultsCorticobulbar excitability of pharyngeal motor cortex was beneficially modulated by PES, PAS and to a lesser extent by rTMS, with functionally relevant changes in the unaffected hemisphere. Following combining the results of real neurostimulation, an overall increase in corticobulbar excitability in the unaffected hemisphere (P = .005, F1,17 = 10.6, ANOVA) with an associated 15% reduction in aspiration (P = .005, z = −2.79) was observed compared to sham. ConclusionsIn this mechanistic study, an increase in corticobulbar excitability the unaffected projection was correlated with the improvement in swallowing safety (P = .001, rho = −.732), but modality-specific differences were observed. Paradigms providing peripheral input favored change in neurophysiological and behavioral outcome measures in chronic dysphagia patients. Further larger cohort studies of neurostimulation in chronic dysphagic stroke are imperative.

Post‐stroke dysphagia: progress at last

Oropharyngeal Dysphagia (OD) is both underestimated and underdiagnosed as a cause of malnutrition and respiratory complications following stroke. OD occurs in more than 50% of stroke patients. Aspiration pneumonia (AP) occurs in up to 20% of acute stroke patients and is a major cause of mortality after discharge. Systematic screening for OD should be performed on every patient with stroke before starting oral feeding, followed, if appropriate by clinical and instrumental (videofluroscopy and/or fiberoptic endoscopy) assessment. Bolus modification with adaptation of texture and viscosity of solids and fluids and postural adjustments should be part of the minimal treatment protocol, but they do not change the impaired swallow physiology nor promote recovery of damaged neural swallow networks in stroke patients. To this purpose, two new neurostimulation approaches are being developed to stimulate cortical neuroplasticity to recover swallowing function: (i) those aimed at stimulating the peripheral oropharyngeal sensory system by chemical, physical or electrical stimulus; and (ii) those aimed at directly stimulating the pharyngeal motor cortex, such as repetitive transcranial magnetic stimulation (rTMS). The study of Park et al. in this issue of Neurogastroenterology and Motility evaluated the effect of rTMS in dysphagic stroke patients and showed a marked improvement in swallow physiology. Other studies also using rTMS showed plastic changes in pharyngeal motor cortical areas relevant to swallowing function. If further randomized controlled trials confirm these initial results, the neurorehabilitation strategies will be introduced to clinical practice sooner rather than later, improving the recovery of dysphagic stroke patients. Progress at last.

Priming Pharyngeal Motor Cortex by Repeated Paired Associative Stimulation

Background. Several stimulation parameters can influence the neurophysiological and behavioral effects of paired associative stimulation (PAS), a neurostimulation paradigm that repeatedly pairs a peripheral electrical with a central cortical (transcranial magnetic stimulation [TMS]) stimulus. This also appears to be the case when PAS is applied to the pharyngeal motor cortex (MI), with some variability in excitatory responses, questioning its translation into a useful therapy for patients with brain injury. Objective. To investigate whether repeated PAS in both “responders” and “nonresponders” could enhance cortical excitability in pharyngeal MI more robustly. Methods. Based on their responses after single PAS, healthy participants were stratified into 2 groups of “responders” and “nonresponders” and underwent 2 periods (60 minutes inter-PAS interval) of active and sham PAS in a randomized order. Neurophysiological measurements with single TMS pulses from pharyngeal motor representation were collected up to 90 minutes after the second PAS period. Results. Repeated PAS increased cortical excitability up to 95% at 60 minutes following the second PAS in both the “responders” and “nonresponders.” Moreover, cortical excitability in the “nonresponders” was significantly different after repeated PAS compared with single and sham application (P = .02; z = −2.2). Conclusions. Double dose PAS switched “nonresponders” to “responders.” These results are important for PAS application to dysphagic stroke patients who do not initially respond to a single application.

Interventions for dysphagia and nutritional support in acute and subacute stroke

Dysphagia (swallowing problems) are common after stroke and can cause chest infection and malnutrition. Dysphagic, and malnourished, stroke patients have a poorer outcome. To assess the effectiveness of interventions for the treatment of dysphagia (swallowing therapy), and nutritional and fluid supplementation, in patients with acute and subacute (within six months from onset) stroke. We searched the Cochrane Stroke Group Trials Register (February 2012), MEDLINE (1966 to July 2011), EMBASE (1980 to July 2011), CINAHL (1982 to July 2011) and Conference Proceedings Citation Index- Science (CPCI-S) (1990 to July 2011). We also searched the reference lists of relevant trials and review articles, searched Current Controlled Trials and contacted researchers (July 2011). For the previous version of this review we contacted the Royal College of Speech and Language Therapists and equipment manufacturers. Randomised controlled trials (RCTs) in dysphagic stroke patients, and nutritional supplementation in all stroke patients, where the stroke occurred within six months of enrolment. Two review authors independently applied the inclusion criteria, assessed trial quality, and extracted data, and resolved any disagreements through discussion with a third review author. We used random-effects models to calculate odds ratios (OR), 95% confidence intervals (95% CI), and mean differences (MD). The primary outcome was functional outcome (death or dependency, or death or disability) at the end of the trial. We included 33 studies involving 6779 participants.Swallowing therapy: acupuncture, drug therapy, neuromuscular electrical stimulation, pharyngeal electrical stimulation, physical stimulation (thermal, tactile), transcranial direct current stimulation, and transcranial magnetic stimulation each had no significant effect on case fatality or combined death or dependency. Dysphagia at end-of-trial was reduced by acupuncture (number of studies (t) = 4, numbers of participants (n) = 256; OR 0.24; 95% CI 0.13 to 0.46; P < 0.0001; I(2) = 0%) and behavioural interventions (t = 5; n = 423; OR 0.52; 95% CI 0.30 to 0.88; P = 0.01; I(2) = 22%). Route of feeding: percutaneous endoscopic gastrostomy (PEG) and nasogastric tube (NGT) feeding did not differ for case fatality or the composite outcome of death or dependency, but PEG was associated with fewer treatment failures (t = 3; n = 72; OR 0.09; 95% CI 0.01 to 0.51; P = 0.007; I(2) = 0%) and gastrointestinal bleeding (t = 1; n = 321; OR 0.25; 95% CI 0.09 to 0.69; P = 0.007), and higher feed delivery (t = 1; n = 30; MD 22.00; 95% CI 16.15 to 27.85; P < 0.00001) and albumin concentration (t = 3; n = 63; MD 4.92 g/L; 95% CI 0.19 to 9.65; P = 0.04; I(2) = 58%). Although looped NGT versus conventional NGT feeding did not differ for end-of-trial case fatality or death or dependency, feed delivery was higher with looped NGT (t = 1; n = 104; MD 18.00%; 95% CI 6.66 to 29.34; P = 0.002). Timing of feeding: there was no difference for case fatality, or death or dependency, with early feeding as compared to late feeding. Fluid supplementation: there was no difference for case fatality, or death or dependency, with fluid supplementation. Nutritional supplementation: there was no difference for case fatality, or death or dependency, with nutritional supplementation. However, nutritional supplementation was associated with reduced pressure sores (t = 2; n = 4125; OR 0.56; 95% CI 0.32 to 0.96; P = 0.03; I(2) = 0%), and, by definition, increased energy intake (t = 3; n = 174; MD 430.18 kcal/day; 95% CI 141.61 to 718.75; P = 0.003; I(2) = 91%) and protein intake (t = 3; n = 174; MD 17.28 g/day; 95% CI 1.99 to 32.56; P = 0.03; I(2) = 92%). There remains insufficient data on the effect of swallowing therapy, feeding, and nutritional and fluid supplementation on functional outcome and death in dysphagic patients with acute or subacute stroke. Behavioural interventions and acupuncture reduced dysphagia, and pharyngeal electrical stimulation reduced pharyngeal transit time. Compared with NGT feeding, PEG reduced treatment failures and gastrointestinal bleeding, and had higher feed delivery and albumin concentration. Nutritional supplementation was associated with reduced pressure sores, and increased energy and protein intake.

Taste and Temperature in Swallowing Transit Time after Stroke

Background: Oropharyngeal dysphagia is common in individuals after stroke. Taste and temperature are used in dysphagia rehabilitation. The influence of stimuli, such as taste and temperature, on swallowing biomechanics has been investigated in both healthy individuals and in individuals with neurological disease. However, some questions still remain unanswered, such as how the sequence of offered stimuli influences the pharyngeal response. The goal of the present study was to determine the influence of the sequence of stimuli, sour taste and cold temperature, on pharyngeal transit time during deglutition in individuals after stroke. Methods: The study included 60 individuals with unilateral ischemic stroke, 29 males and 31 females, aged 41–88 years (mean age: 66.2 years) examined 0–50 days after ictus (median: 6 days), with mild to moderate oropharyngeal dysphagia. Exclusion criteria were hemorrhagic stroke patients, patients with decreased level of consciousness, and clinically unstable patients, as confirmed by medical evaluation. The individuals were divided into two groups of 30 individuals each. Group 1 received a nonrandomized sequence of stimuli (i.e. natural, cold, sour, and sour-cold) and group 2 received a randomized sequence of stimuli. A videofluoroscopic swallowing study was performed to analyze the pharyngeal transit time. Four different stimuli (natural, cold, sour, and sour-cold) were offered. The images were digitalized and specific software was used to measure the pharyngeal transit time. Since the values did not present regular distribution and uniform variances, nonparametric tests were performed. Results: Individuals in group 1 presented a significantly shorter pharyngeal transit time with the sour-cold stimulus than with the other stimuli. Individuals in group 2 did not show a significant difference in pharyngeal transit time between stimuli. Conclusions: The results showed that the sequence of offered stimuli influences the pharyngeal transit time in a different way in individuals after stroke and suggest that, when the sour-cold stimulus is offered in a randomized sequence, it can influence the response to the other stimuli in stroke patients. Hence, the sour-cold stimulus could be used as a therapeutic aid in dysphagic stroke patients.

Acquisition of oral intake in severely dysphagic patients with acute stroke: A single-center, observational study involving a database of 4972 consecutive stroke patients

ObjectiveA single-center, observational study was performed to identify the predictors for oral intake 3months after onset in stroke patients with severe dysphagia. MethodsOf 4972 consecutive acute stroke patients, 723 could not eat orally on day 10. Three months after onset, a questionnaire was sent to all patients. Those who survived and replied to the questionnaire were divided into 2 groups, and the clinical factors that predicted their acquisition of oral intake were analyzed. ResultsOf the 586 dysphagic patients who responded, 141 (24.2%) achieved oral intake after 3months. On logistic-regression model analysis, age ≤80years, hyperlipidemia, non-cardioembolic stroke, modified Rankin Scale score 0 before onset, and National Institutes of Health Stroke Scale (NIHSS) score were independently related to oral intake 3months after onset. From two different model analyses, NIHSS score ≤17 on day 10 (OR 3.58, 95% CI, 2.35–5.54) was found to be a stronger predictor for oral intake than NIHSS score ≤17 on admission (OR 2.17, 95% CI, 1.40–3.39). ConclusionIn severely dysphagic acute stroke patients, functional independence at baseline, younger age, absence of hyperlipidemia, non-cardioembolic stroke, and a milder NIHSS score on day 10 are useful predictors of the resumption of oral intake.

Application of Ultrasonography in Assessing Oropharyngeal Dysphagia in Stroke Patients

This study applied submental ultrasonography (SUS) to measure changes in dysphagic stroke patients' tongue thickness and hyoid bone displacement when swallowing 5 mL of water and correlated the results with the severity of clinical dysphagia. We included 60 stroke patients (30 tube-feeding-dependent and 30 on regular oral intake) and 30 healthy controls. An additional 10 healthy people were recruited to assess the reliability of SUS. Measurements of hyoid bone displacement using videofluoroscopic swallowing study (VFSS) and SUS were compared for 12 stroke patients to assess the correlation between the two methods. Changes in tongue thickness and hyoid bone displacement were significantly less in the tube-feeding group. Those with a tongue thickness change of less than 1.0 cm and hyoid bone displacement of less than 1.5 cm were likely to be tube-feeding. SUS showed good intra-rater/inter-rater reliability and correlated well with VFSS measurement. SUS can be an adjunct assessment tool of swallowing.

OC-092 Contralesional application of the novel brain stimulation intervention transcranial direct current stimulation (TDCS) restores brain and swallowing function in the human pharyngeal motor cortex

IntroductionRecovery of swallowing function in unilateral dysphagic stroke patients is associated with increased pharyngeal motor cortex excitability of the unlesioned hemisphere. “Virtual-lesioning” the human pharyngeal motor cortex transiently disrupts swallowing...

The efficacy of low-frequency electrical acupoint stimulation plus rehabilitation training in improving the swallowing function of stroke survivors

Objective To test the efficacy of low-frequency electrical acupoint stimulation plus rehabilitation training in improving swallowing function after stroke. Methods Eighty dysphagic stroke patients were randomly allocated into 2 groups of 40.Patients in the experimental group received low-frequency electrical acupoint stimulation plus 2 courses of rehabilitation training.Control group patients received the same protocol,but the electrical stimulation was not over acupoints.Their swallowing function was assessed using the Kubota water drinking test.Results After treatment,both groups showed significantly lower Kubota scores compared with pre-treatment.Prepost test difference was 1.25 ± 0.78 in the experimental group and 0.70 ± 0.72 in the control group,a significant difference.The total recovery rate in the experimental group was 87.5％.In the control group it was 55％.The improvement in swallowing function was significantly better in the experimental group. Conclusion Both groups showed a significant improvement in swallowing function,but low-frequency electrical acupoint stimulation increased the effectiveness of the rehabilitation training. Key words: Dysphagia; Acupoints; Low-frequency electrical stimulation; Stroke

Noninvasive Brain Stimulation May Improve Stroke-Related Dysphagia

Treatment options for stroke-related dysphagia are currently limited. In this study, we investigated whether noninvasive brain stimulation in combination with swallowing maneuvers facilitates swallowing recovery in dysphagic stroke patients during early stroke convalescence. Fourteen patients with subacute unilateral hemispheric infarction were randomized to anodal transcranial direct current stimulation (tDCS) versus sham stimulation to the sensorimotor cortical representation of swallowing in the unaffected hemisphere over the course of 5 consecutive days with concurrent standardized swallowing maneuvers. Severity of dysphagia was measured using a validated swallowing scale, Dysphagia Outcome and Severity scale, before the first and after the last session of tDCS or sham. The effect of tDCS was analyzed in a multivariate linear regression model using changes in Dysphagia Outcome and Severity Scale as the outcome variable after adjusting for the effects of other potential confounding variables such as the National Institutes of Health Stroke Scale and Dysphagia Outcome and Severity scale scores at baseline, acute ischemic lesion volumes, patient age, and time from stroke onset to stimulation. Patients who received anodal tDCS gained 2.60 points of improvement in Dysphagia Outcome and Severity scale scores compared to patients in the sham stimulation group who showed an improvement of 1.25 points (P=0.019) after controlling for the effects of other aforementioned variables. Six out 7 (86%) patients in tDCS stimulation group gained at least 2 points of improvement compared with 3 out 7 (43%) patients in the sham group (P=0.107). Because brain stem swallowing centers have bilateral cortical innervations, measures that enhance cortical input and sensorimotor control of brain stem swallowing may be beneficial for dysphagia recovery.

OC-066 A preliminary study of neurostimulation based interventions in the treatment of chronic dysphagia post-stroke

<h3>Introduction</h3> Oropharyngeal dysphagia after stroke has an incidence up to 45% and when chronic, leads to increased risk of institutionalisation and death in the long term. Pharyngeal electrical stimulation (PES),1 repetitive transcranial magnetic stimulation (rTMS)2 and paired associative stimulation (PAS)3 are three neurostimulation techniques developed to increase cortical excitability of pharyngeal motor cortex, with therapeutic potential. However the effects of these techniques on chronic but stable swallowing problems in stroke patients remain unknown. We therefore investigated the effects of these interventions in stroke patients with dysphagia persisting for &gt;6 weeks. <h3>Methods</h3> In 12 dysphagic stroke patients (69±9 years (mean±SD), 79±25 weeks post-stroke (mean±SD), 6 left, 5 right hemispheric, 1 undetermined) pharyngeal electromyographic responses were recorded using an intraluminal catheter after the application of single TMS pulses over pharyngeal motor cortex, in order to measure cortico-bulbar excitability before, immediately and 30 minutes after real and sham applications of either: a) PES (10 mins of 5 Hz), b) rTMS (250 repeated TMS pulses at 5 Hz), or c) PAS (10 mins of repeated pairs of pharyngeal and TMS pulse every 20 s). In nine subjects, swallowing performance and safety (aspiration-penetration scores, APs) were assessed with videofluoroscopy before and after both real and sham neurostimulation techniques. <h3>Results</h3> Compared to sham, the application of all neurostimulation interventions showed a significant increase in cortical excitability in the unaffected hemisphere by 54%±17% (mean±SEM) immediately post (repeated measures ANOVA p&lt;0.001, Time*Intervention p=0.005), not observed in the affected hemisphere (p=0.12). In addition, after active neurostimulation, APs were reduced by −14%±6% (mean±SEM) compared to sham (Wilcoxon9s test, p=0.05). Moreover, the delay between the oral and pharyngeal phases of swallowing, important for swallowing safety, was shortened by −56%±13% (mean±SEM) after real neurostimulation (Wilcoxon9s test, p=0.01) compared to sham. There was no consistent difference in cortical or swallowing response between the interventions. <h3>Conclusion</h3> These preliminary results show that neurostimulation interventions have beneficial neurophysiological and behavioural effects in chronic stroke patients with dysphagia, increasing cortical excitability and improving swallowing safety. These findings provide support for neurostimulation being a useful adjunct in swallowing rehabilitation, even in chronic neurologic illness, and lay the foundation for further clinical trials of these forms of intervention.

Adjunctive Functional Pharyngeal Electrical Stimulation Reverses Swallowing Disability After Brain Lesions

Oropharyngeal dysphagia is an important disability that occurs after stroke; it contributes to aspiration pneumonia and death, and current modalities for rehabilitation of dysphagia have uncertain efficacy. We therefore examined the role of pharyngeal electrical stimulation (PES) in expediting human swallowing recovery after experimental (virtual) and actual (stroke) brain lesions. First, healthy subjects (n = 13) were given 1-Hz repetitive transcranial magnetic stimulation to induce a unilateral virtual lesion in pharyngeal motor cortex followed by active or sham (control) PES. Motor-evoked potentials and swallow accuracy were recorded before and after the lesion to assess PES response. Thereafter, 50 acute dysphagic stroke patients underwent either a dose-response study, to determine optimal parameters for PES (n = 22), or were assigned randomly to groups given either active or sham (control) PES (n = 28). The primary end point was the reduction of airway aspiration at 2 weeks postintervention. In contrast to sham PES, active PES reversed the cortical suppression induced by the virtual lesion (F(7,70) = 2.7; P = .015) and was associated with improvement in swallowing behavior (F(3,42) = 5; P = .02). After stroke, 1 PES treatment each day (U = 8.0; P = .043) for 3 days (U = 10.0) produced improved airway protection compared with controls (P = .038). Active PES also reduced aspiration (U = 54.0; P = .049), improved feeding status (U = 58.0; P = .040), and resulted in a shorter time to hospital discharge (Mantel-Cox log-rank test, P = 0.038). This pilot study of PES confirms that it is a safe neurostimulation intervention that reverses swallowing disability after virtual lesion or stroke.