Dysphagia following brain-stem stroke. Clinical correlates and outcome

Fiberoptic Endoscopy Evaluation of Swallowing (FEES) Findings Associated with High Pneumonia Risk in a Cohort of Patients at Risk of Dysphagia

Aspiration detected in the fiberoptic endoscopy evaluation of swallowing (FEES) has been inconsistently associated with pneumonia, with no evidence of the risk of pneumonia from other alterations in swallowing safety detected in FEES. We conducted a dynamic, ambidirectional cohort study involving 148 subjects at risk of dysphagia in a tertiary university hospital. Our aim was to determine the risk of pneumonia attributed to alterations in swallowing safety detected during FEES. We used multivariate negative binomial regression models to adjust for potential confounders. The incidence density rate (IR) of pneumonia in patients with tracheal aspiration of any consistency was 26.6/100 people-years (RR 7.25; 95% CI: 3.50-14.98; P < 0.001). The IR was 19.7/100 people-years (RR 7.85; 95% CI: 3.34-18.47; P < 0.001) in those with laryngeal penetration of any consistency and 18.1/100 people-years (RR 6.24; 95% CI: 2.58-15.09; P < 0.001) in those with pharyngeal residue of any consistency. When adjusted for aspiration, the association of residue and penetration with pneumonia disappeared, suggesting that their risk of pneumonia is dependent on the presence of aspiration and that only aspiration is independently associated with pneumonia. This increased risk of pneumonia was significant in uni- and multivariate negative binomial regression models. We found an independently increased risk of pneumonia among patients with dysphagia and aspiration detected during FEES. Alterations in the oral and pharyngeal phases of swallowing, without aspiration, did not increase the risk of pneumonia.

The effectiveness of chin-down manoeuvre in patients with dysphagia: A systematic review and meta-analysis

AIM

The chin-down posture is a widely used compensatory manoeuvre for patients with dysphagia. The aim of this study was designed to systematically measure the effectiveness of chin-down manoeuvre application.

METHODOLOGY

We retrieved the PubMed, Web of Science, Embase, Cochrane Library, EBSCO, Medline, CNKI, WANFANG, VIP and SinoMed databases from inception to 30 August 2022. Raters independently screened literature according to inclusion and exclusion criteria. The quality of the included literature was evaluated, and data were extracted. The software Review Manager software 5.3 was used for statistical analysis.

RESULTS

Fourteen studies with a total of 571 patients were included in this meta-analysis. The meta-analysis indicated that chin-down manoeuvre could significantly reduce the risk of aspiration (MD = -1.35, 95% CI [-2.25, -0.44], Z = 2.92, p < .01), decrease the chin angle (MD = -12.20, 95% CI [-14.61, -9.79], Z = 9.91, p < .001), shorten oral transit time (MD = -0.81, 95% CI [-1.20, -0.43], Z = 4.17, p < .001), reduce the maximum swallowing pressure at upper oesophageal sphincter (MD = -82.07, 95% CI [-112.77, -51.37], Z = 5.24, p < .001) and decrease pharyngeal residue.

CONCLUSIONS

Existing evidence indicated that chin-down manoeuvre could reduce the risk of aspiration and pharyngeal residue, decrease the maximum swallowing pressure at UES. More large-sample, high-quality clinical trials are still needed in the future to further ascertain the results of this research.

Clinical Features and Voxel-Based-Symptom-Lesion Mapping of Silent Aspiration in Acute Infratentorial Stroke

Post-stroke dysphagia (PSD) is a severe and common complication after ischemic stroke. The role of silent aspiration as an important contributing factor in the development of a dysphagia-associated complications, in particular aspiration-associated pneumonia has been insufficiently understood. The aim of this study was to investigate the characteristics and risk factors of silent aspiration in patients with acute infratentorial stroke by FEES and to identify culprit lesions in stroke patient with a high risk of silent aspiration via voxel-based-symptom-lesion mapping (VBS/ML). This study is a retrospective observational study based on a prospectively collected FEES and stroke database. Consecutive patient cases with acute ischemic infratentorial stroke and FEES examination between 2017 and 2022 were identified. Group allocation was performed based on PAS scores. Imaging analysis was performed by manual assignment and by VBS/ML. Group comparisons were performed to assess silent aspiration characteristics. Binary logistic regression analysis was performed to determine if baseline clinical, demographic, and imaging parameters were helpful in predicting silent aspiration in patients. In this study 84 patient cases with acute infratentorial stroke who underwent FEES examination were included. Patients were moderately affected at admission (mean NIH-SS score at admission 5.7 SD ± 4.7). Most lesions were found pontine. Overall 40.5% of patients suffered from silent aspiration, most frequently in case of bilateral lesions. Patients with silent aspiration had higher NIH-SS scores at admission (p < 0.05), had a more severe swallowing disorder (p < 0.05) and were 4.7 times more likely to develop post-stroke pneumonia. Patients who underwent FEES examination later than 72 h after symptom onset were significantly more likely to suffer from silent aspiration and to develop pneumonia compared to patients who underwent FEES examination within the first 72 h (p < 0.05). A binary logistic regression model identified NIH-SS at admission as a weak predictor of silent aspiration. Neither in manual assignment of the lesions to brain regions nor in voxel-wise statistic regression any specific region was useful in prediction of silent aspiration. Silent aspiration is common in patients with infratentorial stroke and contributes to the risk for pneumonia. Patients with silent aspiration are more severely affected by stroke, but cannot reliably be identified by NIH-SS at admission or lesion location. Patients suffering from acute infratentorial stroke should been screened and examined for PSD and silent aspiration.

One-Year Survival of Ischemic Stroke Patients Requiring Mechanical Ventilation

BACKGROUND

The outcome of patients with acute ischemic stroke who require mechanical ventilation has been poor. Intubation due to a reversible condition could be associated with better 1-year survival.

METHODS

All adult patients treated in Helsinki University Hospital in 2016-2020 who were admitted because of an ischemic stroke (either stroke or thrombosis seen on imaging) and needed mechanical ventilation were included in this retrospective cohort study. Data on demographics, medical history, index stroke, and indication for intubation were collected. The primary outcome was 1-year mortality. Secondary outcomes were modified Rankin Scale (mRS) score at 3 months and living arrangements at 1 year.

RESULTS

The mean age of the cohort (N = 121) was 66 ± 11 (mean ± SD) years, and the mean admission National Institutes of Health Stroke Scale score was 17 ± 10. Forty-four (36%) patients were male. The most common indication for intubation was unconsciousness (51%), followed by respiratory failure or airway compromise (28%). One-year mortality was 55%. Three-month mRS scores were available for 114 (94%) patients, with the following distribution: 0-2, 18%; 3-5, 28%; and 6 (dead), 54%. Of the 1-year survivors, 72% were living at home. In the multivariate analysis, only age over 75 years and intubation due to unconsciousness, respiratory failure, or cardiac arrest remained significantly associated with mortality.

CONCLUSIONS

The indication for intubation seems to significantly affect outcome. Functional outcome at 3 months is often poor, but a great majority of 1-year survivors are able to live at home.

Characteristics of post-stroke dysphagia: A retrospective study based on FEES

OBJECTIVE

This study aims to examine the characteristics of dysphagia in stroke patients with different lesion sites and explore the factors that impact the duration of nasogastric tube after post-stroke dysphagia (PSD).

METHODS

Patients with PSD were screened for analysis. Stroke types and lesion sites were confirmed using MRI or CT scans. Included patients were categorized into two groups: supratentorial stroke group (including lobar and deep intracerebral stroke subgroups) and infratentorial stroke group (including brainstem and cerebellar stroke subgroups). Fiberoptic endoscopic evaluation of swallowing (FEES), Penetration-aspiration scale (PAS), Yale pharyngeal residue (PR) severity rating scale, Functional oral intake scale (FOIS), Murray secretion severity rating scale (MSS), laryngopharyngeal sensation, and vocal fold mobility were investigated to assess the swallowing function.

RESULTS

A total of 94 patients were included in the final analysis. Significant differences were found in PR scores (p < .001), PAS scores (p < .05), MSS scores (p < .05), and vocal fold mobility (p < .001) between infratentorial and supratentorial stroke groups. Moreover, lobar stroke showed significantly higher PR scores compared to the deep intracerebral stroke group (p < .05). Kaplan-Meier survival analysis indicated significant differences in the duration of nasogastric tube placement among the following groups: infratentorial versus supratentorial stroke, PAS ≤ 5 versus PAS > 5, PR ≥ 3 versus PR < 3, and normal vocal fold mobility versus vocal fold motion impairment group (p < .05).

CONCLUSIONS

The infratentorial stroke may lead to worse swallowing function as compared to a supratentorial stroke. Additionally, patients with infratentorial stroke, PAS > 5, PR ≥ 3, or vocal fold motion impairment may contribute to a longer duration of nasogastric tube placement.

Generating Items for a Novel Bedside Dysphagia Screening Tool Post Acute Pediatric Stroke

Bedside dysphagia assessment protocols are not well developed in acute pediatric stroke unlike adults. The objective of this study was to identify items deemed relevant and feasible by expert consensus to inform the development of a bedside dysphagia screening tool for acute pediatric stroke. A two-phase study was conducted: (1) literature review and expert consultation generated a comprehensive list of dysphagia assessment items; (2) items were formatted in an online survey asking respondents opinion of relevance to acute pediatric stroke and feasibility for bedside administration by a trained health professional. The Dillman Tailored Design approach optimized response rate. Respondents were identified using the snowball method. Speech-language pathologists with > 2 years in pediatric dysphagia were invited to complete the survey. Demographic and practice variables were compared using univariate statistics. Item relevance and feasibility were made using binary or ordinal responses, combined to derive item-content validity indices (I-CVI) to guide item reduction. Items with I-CVI > 0.78 (excellent content validity) were moved forward to tool development. Of the 71 invited respondents, 57(80.3%) responded, of which 34(59.6%) were from North America. Sixty-one items were generated of which 4(6.6%) items were rated 'to keep'. These were face symmetry (I-CVI:0.89), salivary control (I-CVI:0.95), alertness (I-CVI:0.89) and choking (I-CVI:0.84). Of all respondents, 31(54.4%) endorsed swallowing trials, of which 25(80.6%) endorsed thin liquid by teaspoon (n = 17, 68%) or open cup (n = 20, 80%). We identified candidate items for bedside dysphagia screening with excellent content validity for acute pediatric stroke patients. Next steps include assessment of the psychometric value of each item in identifying dysphagia in children in the acute stage of recovery from stroke.

Surgical landmarks for identification and preservation of the internal branch of the superior laryngeal nerve

OBJECTIVE

To determine the topographical anatomic features of the internal branch of the superior laryngeal nerve (ibSLN) at the thyrohyoid membrane entrance area in relation to certain consistent anatomical structures.

MATERIALS

METHODS: Twenty-two fresh adult head cadavers (9 male, 13 female; age range 52-95 years) with no signs of abnormality in the neck were dissected to determine the anatomic relationship of ibSLN and superior border of thyroid cartilage, thyroid notch, carotid bifurcation, hyoid corpus, and hyoid greater cornu.

RESULTS

The topographical relationship between ibSLN and superior border of thyroid cartilage, thyroid notch, carotid bifurcation, hyoid corpus, and hyoid greater cornu was identified bilaterally in all cadavers. According to the measures, danger zone and safe zone areas for surgical could be predicted and for surgical manipulations as well.

CONCLUSION

We provided the surgical anatomy and important landmarks for determining the internal branch of superior laryngeal nerve in the thyrohyoid membrane entrance region to avoid surgical damage during surgeries of this region.

Post-Stroke Pneumonia in Real-World Practice: Background, Microbiological Examination, and Treatment

Post-stroke pneumonia (PSP) has an impact on acute ischemic stroke (AIS). Although predictive scores for PSP have been developed, it is occasionally difficult to predict. Clarifying how PSP was treated after its onset in clinical practice is important. Admitted patients with AIS over a 2-year period were retrospectively reviewed. Of 281 patients with AIS, 24 (8.5%) developed PSP. The integer-based pneumonia risk score was higher in patients with PSP. The onset of PSP was frequently seen up to the 4th day of hospitalization. Of patients with PSP, sputum examination yielded Geckler 4 or 5 in only 8.3%. Angiotensin-converting enzyme inhibitor (ACE-I) was more frequently administered to patients with PSP; however, all these cases were started with ACE-I following PSP onset. Nasogastric tubes (NGTs) were inserted in 16 of the patients with PSP, of whom 11 were inserted following PSP onset. Multivariate analysis showed that PSP onset was a poor prognostic factor independent of the female sex, urinary tract infection, and National Institutes of Health Stroke Scale. PSP treatment would benefit from the administration of antimicrobials and ACE-I, as well as NGT insertion. To select effective agents for PSP and evaluate the indications for NGT insertion, further case studies are needed.

Listening for Dysphagia: Voice Quality Sequelae of Material in the Airway

PURPOSE

Postswallow voice abnormality is often assumed to indicate the presence of material in the laryngeal airway (MIA), but prior research has not shown definitive evidence of a causal relationship. This study investigated if endoscopically confirmed MIA (prandial material or secretions) generates specific voice quality attributes that can be perceptually identified by experienced listeners.

METHOD

Forty-four dysphagic adults underwent endoscopic evaluation of swallowing. Time-linked audiovisual recordings of pre- and postswallow phonation were analyzed to determine the presence, amount, and location of prandial material or secretions in the larynx during phonation. Expert listeners completed auditory-perceptual ratings of phonation samples.

RESULTS

Voice quality ratings did not differ significantly when there was MIA during postswallow phonation. However, judgments of voice quality abnormality for MIA samples were elevated when analyses controlled for effects of baseline dysphonia. Listeners were most likely to perceive voice quality abnormality when larger amounts of secretions were present, as compared to prandial material. Interrater reliability was variable and ranged from low to moderate across perceptual parameters.

CONCLUSIONS

MIA during phonation occurred for many participants, but perception of voice quality abnormality was variable when MIA was present. Baseline dysphonia is common among individuals with dysphagia and may limit perception of voice quality abnormalities generated by MIA. Secretions in the laryngeal airway may have a greater impact on voice quality parameters.

Altered Brain Function Activity in Patients With Dysphagia After Cerebral Infarction: A Resting-State Functional Magnetic Resonance Imaging Study

Objective

Dysphagia after cerebral infarction (DYS) has been detected in several brain regions through resting-state functional magnetic resonance imaging (rs-fMRI). In this study, we used two rs-fMRI measures to investigate the changes in brain function activity in DYS and their correlations with dysphagia severity.

Method

In this study, a total of 22 patients with DYS were compared with 30 patients without dysphagia (non-DYS) and matched for baseline characteristics. Then, rs-fMRI scans were performed in both groups, and regional homogeneity (ReHo) and fractional amplitude of low-frequency fluctuation (fALFF) values were calculated in both groups. The two-sample t-test was used to compare ReHo and fALFF between the groups. Pearson's correlation analysis was used to determine the correlations between the ReHo and fALFF of the abnormal brain regions and the scores of the Functional Oral Intake Scale (FOIS), the Standardized Bedside Swallowing Assessment (SSA), the Videofluoroscopic Swallowing Study (VFSS), and the Penetration-Aspiration Scale (PAS).

Results

Compared with the non-DYS group, the DYS group showed decreased ReHo values in the left thalamus, the left parietal lobe, and the right temporal lobe and significantly decreased fALFF values in the right middle temporal gyrus and the inferior parietal lobule. In the DYS group, the ReHo of the right temporal lobe was positively correlated with the SSA score and the PAS score (r = 0.704, p < 0.001 and r = 0.707, p < 0.001, respectively) but negatively correlated with the VFSS score (r = −0.741, p < 0.001). The ReHo of the left parietal lobe was positively correlated with SSA and PAS (r = 0.621, p = 0.002 and r = 0.682, p < 0.001, respectively) but negatively correlated with VFSS (r = −0.679, p = 0.001).

Conclusion

The changes in the brain function activity of these regions are related to dysphagia severity. The DYS group with high ReHo values in the right temporal and left parietal lobes had severe dysphagia.

Post-stroke Dysphagia: Prognosis and Treatment-A Systematic Review of RCT on Interventional Treatments for Dysphagia Following Subacute Stroke

Purpose

Post-stroke dysphagia is an underdiagnosed but relevant complication, associated with worse outcome, dependency and quality of life of stroke survivors. Detailed mechanisms of post-stroke dysphagia are not very well understood, but established therapeutic concepts are needed. Different interventional studies have been published dealing with post-stroke dysphagia. This systematic review wants to collect and give an overview over the published evidence.

Methods

PubMed, Embase, Cochrane, CINAHL were searched for relevant interventional studies on post-stroke dysphagia in the (sub-)acute setting (within 3 months of stroke onset). The search has been filtered for randomized trials with an inactive control and the relevant data extracted.

Results

After initially finding 2,863 trials, finally 41 trials have been included. Seven different therapeutic concepts have been evaluated (Acupuncture, behavioral/physical therapy, drug therapy, neuromuscular electrical stimulation, pharyngeal electrical stimulation, transcranial direct current stimulation and repetitive transcranial magnetic stimulation). Studies of all modalities have shown some effect on post-stroke dysphagia with several studies raising concerns about the potential bias.

Conclusion

The amount and quality of studies are not enough to suggest certain therapies. Some therapeutical concepts (intensive physical therapy, transcranial magnetic stimulation, drug therapy) seem to be good potential therapeutic options, but further research is needed.

A Novel Balloon Catheter-based Dilation Intervention for Patients with Cricopharyngeus Achalasia After Stroke: A Randomized Study

This study aimed to investigate the efficacy and safety of a novel balloon catheter in dilation intervention for patients with cricopharyngeus achalasia after stroke. Thirty-four patients with cricopharyngeus achalasia after stroke received routine swallowing rehabilitation training and were randomly assigned to an experimental group (Exp, n = 17) that received dilation therapy using the novel balloon catheter once daily for 5 days per week or a control group (Con, n = 17) that received dilation therapy with a 14-Fr ordinary urinary catheter once daily for 5 days per week. The intervention duration, Eating Assessment Tool (EAT)-10 scores, and Functional Oral Intake Scale (FOIS) scores were recorded at baseline and each day during intervention. The time for a patient's FOIS score to be ≥ 3 as well as the recovery time for oral intake of water, liquid food, mushy food, and solid food were recorded or estimated. Complications were also recorded during intervention. The intervention duration was shorter in the Exp group than in the Con group (p = 0.005). The Exp group patients improved faster than the Con group patients, with a shorter recovery time for oral intake of liquid food (p = 0.002), mushy food (p = 0.001), and solid food (p = 0.001). At the time of intervention termination, EAT-10 scores were lower in the Exp group than in the Con group (p = 0.005). The Exp group had a similar incidence of complications as the Con group but with better tolerability (p = 0.028). Compared with the urinary catheter, the novel balloon catheter for dilation in patients with cricopharyngeus achalasia after stroke may lead to a better and more rapid recovery.

Post-stroke palatal tremor as a clinical predictor of dysphagia and its neuroanatomical correlates in patients with midbrain and pontine lesions

The precise associations between dysphagia and palatal tremor (PT) remain unknown. We aimed to identify the association between PT and dysphagia among patients with midbrain/pontine stroke, compare the characteristics of dysphagia between patients with PT (PT + dysphagia) and without PT (PT- dysphagia), and verify neuroanatomical predictors of PT + dysphagia in this patient population. This retrospective observational study enrolled 40 patients (34 males, 6 females; mean age: 95% confidence interval [CI], 56.6 ± 14.6 years) with first-ever midbrain or pontine stroke exhibiting brain stem lesions admitted to the stroke unit of a single rehabilitation hospital between January 2010 and April 2020. Main outcome measures included dysphagia and aspiration rates and videofluoroscopic swallowing study findings. Lesion localization was stratified according to established vascular territories. Associations between PT and dysphagia and lesion location according to PT and dysphagia were analyzed. Dysphagia and aspiration rates were greater among patients with PT than among those without PT (95% CI, p = 0.030 and p = 0.017, respectively). The proportion of patients exhibiting oral stage impairment (95% CI, p = 0.007) was greater in the PT + dysphagia group than in the PT- dysphagia group. The posterolateral portion of the midbrain and pons (95% CI, p = 0.001 and p < 0.001, respectively) were the lesions more often involved in the PT + dysphagia group. Patients with PT following midbrain/pontine stroke more frequently present with dysphagia than those without PT. Thus, they should be carefully examined for PT and delayed dysphagia, including oral stage impairment, if initial brain images show posterolateral midbrain and pons lesions.

The influence of pharyngeal width on post-stroke laryngeal aspiration

BACKGROUND

Laryngeal penetration, which is a less serious form of aspiration, should be considered in patients with stroke to ensure early detection of risk of laryngeal aspiration and prevention of pneumonia.

OBJECTIVE

As a follow-up to a previous study that demonstrated the association of pharyngeal width to laryngeal aspiration, the present study sought to determine whether the pharyngeal width was related to not only laryngeal aspiration but also laryngeal penetration in patients with deglutition disorder following stroke.

METHODS

The pharyngeal width on the roentgenogram was measured and compared based on the severity of aspiration. Moreover, the optimal cut-off points were determined for predicting the penetration and aspiration so that the difference between the penetration and the aspiration could be elucidated.

RESULTS

The pharyngeal width of the patients was wider than the controls. The increase of the pharyngeal width by aspiration severity was more evident in the patients with chronic and right cerebral stroke. The optimal cut-off point of the pharyngeal width was approximately 1 mm lesser for the prediction of penetration than for aspiration.

CONCLUSIONS

The pharyngeal width could be an ancillary method for detecting penetration and aspiration in stroke patients.

Assessment Across the Life Span: The Clinical Swallow Evaluation

Purpose This clinical focus article considers the roles of the clinical swallow examination (CSE) as a clinically meaningful assessment method used in both adult and pediatric populations. Method This clinical focus article explores the utility of the CSE across the life span. Specifically, components, reliability, standardized assessments, and limitations of the CSE within the adult and pediatric populations are highlighted. Conclusions The CSE remains a crucial assessment tool for the speech-language pathologist. The experienced clinician can make important judgments regarding patient safety and function. If the CSE is conducted mindfully and methodically, findings can help chart the course of care for individuals needing additional assessment and possibly intervention.

First-Hand Experience of Severe Dysphagia Following Brainstem Stroke: Two Qualitative Cases

BACKGROUND

Dysphagia has profound effects on individuals, and living with dysphagia is a complex phenomenon that touches essential areas of life. Dysphagia following a brainstem stroke is often more severe and the chances of spontaneous recovery are less likely as compared with dysphagia following a hemispheric stroke.

OBJECTIVE

To explore how two individuals with brainstem stroke experienced severe dysphagia during their inpatient neurorehabilitation and how they experienced their recovery approximately one month following discharge.

METHODS

An explorative study was conducted to evaluate the first-hand perspective on severe eating difficulties. A qualitative case study was chosen to collect data during two face-to-face semi-structured interviews. Phenomenological perspectives shaped the interview-process and the processing of data.

RESULTS

Analysis of the empirical data generated the following main themes regarding experiences of: (i) the mouth and throat; (ii) shared dining; and (iii) recovery and regression related to swallowing-eating-drinking.

CONCLUSION

Participants expressed altered sensations of the mouth and throat, which affected their oral intake and social participation in meals. Good support for managing and adapting their problems of swallowing, eating, and drinking in daily activities is essential. Knowledge and skills of professionals in relation to dysphagia is a significant requirement for recovery progress in settings within the municipality.

Optimal placement of electrodes for treatment of post-stroke dysphagia by neuromuscular electrical stimulation combined with effortful swallowing

INTRODUCTION

We aimed to determine the optimal placement of electrodes for neuromuscular electrical stimulation (NMES) for post-stroke dysphagia therapy.

METHODS

31 patients with post-stroke dysphagia were randomised to three groups according to NMES electrode placement. In Group A (n = 10), two pairs of electrodes were attached horizontally on the suprahyoid and infrahyoid muscles. In Group B (n = 11), one pair of electrodes was attached horizontally on the suprahyoid muscles while the other was attached vertically on the infrahyoid muscles. In Group C (n = 10), the electrodes were attached vertically, with one pair above the hyoid bone and the other above the cricoid cartilage. All patients received rehabilitation treatment via NMES combined with effortful swallowing training five times weekly for four weeks. The effect of NMES electrode placement was assessed in terms of the Functional Dysphagia Scale (FDS) and Dysphagia Outcome and Severity Scale (DOSS) scores.

RESULTS

Group A showed significantly greater improvement than Group B in overall FDS (p = 0.009) and pharyngeal-phase FDS (FDS-P; p = 0.005) scores. Group A also showed significant improvement when compared with Group C in overall FDS (p = 0.001) and FDS-P (p = 0.001) scores.

CONCLUSION

Horizontal placement of the NMES electrodes on the suprahyoid and infrahyoid muscles for the treatment of post-stroke dysphagia by NMES combined with effortful swallowing was more effective than the horizontal and vertical placement of electrodes on the suprahyoid and infrahyoid muscles, respectively, and their vertical placement above the hyoid bone and cricoid cartilage.

Comparison of Dysphagia Between Infratentorial and Supratentorial Stroke Patients

Objective

To compare dysphagia between infratentorial stroke patients and supratentorial stroke patients.

Methods

Subjects of this study were patients with post-stroke dysphagia (PSD) who were admitted to our medical institution between May 2014 and June 2017. We evaluated a total of 64 patients with PSD. A videofluoroscopic swallowing study (VFSS) was performed to determine dysphagia severity. We measured the following parameters: pharyngeal transit time (PTT), post-swallow pharyngeal remnant, Penetration Aspiration Scale (PAS) scores, and Functional Dysphagia Scale (FDS). We analyzed patient’s results from VFSS performed at admission. All VFSS images were recorded using a camcorder running at 30 frames per second. An AutoCAD 2D screen was used to measure post-swallow pharyngeal remnant.

Results

In this study, PTT and FDS were similar (p>0.05) between infratentorial stroke patients and supratentorial stroke patients. However, there were significant differences in pharyngeal remnant and PAS scores between the two groups (p<0.01 and p<0.05, respectively).

Conclusion

Both pharyngeal remnant and PAS score registered higher levels from VFSS test for infratentorial stroke patients than those for supratentorial stroke patients. This suggests greater chances of problems occurring with swallowing, the major functions of pons. Thus, clinicians should pay particular attention to active dysphagia evaluation and treatment in PSD of infratentorial stroke patients.

Prospective Investigation of Incidence and Co-Occurrence of Dysphagia, Dysarthria, and Aphasia Following Ischemic Stroke

Purpose The high incidence of swallowing and communication disorders following stroke is well documented. However, many of these studies have used retrospective chart reviews to make estimates of incidence and co-occurrence. The current study prospectively examined the incidence and co-occurrence of dysphagia, dysarthria, and aphasia following a 1st occurrence of ischemic stroke at an academic medical center hospital. Method One hundred patients who experienced their 1st ischemic stroke were recruited for participation in this study. All participants received a clinical swallowing evaluation to assess for dysphagia, administration of the Frenchay Dysarthria Assessment-Second Edition ( Enderby & Palmer, 2008 ) and Western Aphasia Battery-Revised ( Kertesz, 2006 ) to screen for the presence of dysarthria and aphasia, respectively. Results Incidence rates of dysphagia, dysarthria, and aphasia were 32%, 26%, and 16%, respectively. Forty-seven percent of participants had at least 1 of these disorders, 28% had 2 of these disorders, and 4% had all 3. Although the incidence rates in this study were smaller in magnitude than incidence rates in previous research, the pattern of results is broadly similar (i.e., dysphagia had the highest incidence rate, followed by dysarthria and, lastly, aphasia). Conclusions This prospective study yielded slightly lower incidence rates than have been previously obtained from retrospective chart reviews. The high incidence and co-occurrence of devastating swallowing and communication disorders post-ischemic stroke provides clear motivation for speech-language pathology involvement in the early phase of stroke rehabilitation.

The Association of 3-D Volume and 2-D Area of Post-swallow Pharyngeal Residue on CT Imaging

Pharyngeal residue, the material that remains in the pharynx after swallowing, is an important marker of impairments in swallowing and prandial aspiration risk. The goals of this study were to determine whether the 2D area of post-swallow residue accurately represents its 3D volume, and if the laterality of residue would affect this association. Thirteen patients with dysphagia due to brainstem stroke completed dynamic 320-detector row computed tomography while swallowing a trial of 10 ml honey-thick barium. 3D volumes of pharyngeal residue were compared to 2D lateral and anterior-posterior areas, and a laterality index for residue location was computed. Although the anteroposterior area of residue was larger than the lateral area, the two measures were positively correlated with one another and with residue volume. On separate bivariate regression analyses, residue volume was accurately predicted by both lateral (R² = 0.91) and anteroposterior (R² = 0.88) residue areas, with limited incidence of high residuals. Half of the sample demonstrated a majority of pharyngeal residue lateralized to one side of the pharynx, with no effect of laterality on the association between areas and volume. In conclusion, the area of post-swallow pharyngeal residue was associated with volume, with limitations in specific cases. Direct measurement of pharyngeal residue volume and swallowing physiology with 3D-CT can be used to validate results from standard 2D instrumentation.

Clinical Effects and Differences in Neural Function Connectivity Revealed by MRI in Subacute Hemispheric and Brainstem Infarction Patients With Dysphagia After Swallowing Therapy

Background: Early detection and intervention for post-stroke dysphagia could reduce the incidence of pulmonary complications and mortality. The aims of this study were to investigate the benefits of swallowing therapy in swallowing function and brain neuro-plasticity and to explore the relationship between swallowing function recovery and neuroplasticity after swallowing therapy in cerebral and brainstem stroke patients with dysphagia.

Methods: We collected 17 subacute stroke patients with dysphagia (11 cerebral stroke patients with a median age of 76 years and 6 brainstem stroke patients with a median age of 70 years). Each patient received swallowing therapies during hospitalization. For each patient, functional oral intake scale (FOIS), functional dysphagia scale (FDS) and 8-point penetration-aspiration scale (PAS) in videofluoroscopy swallowing study (VFSS), and brain functional magnetic resonance imaging (fMRI) were evaluated before and after treatment.

Results: FOIS (p = 0.003 in hemispheric group and p = 0.039 in brainstem group) and FDS (p = 0.006 in hemispheric group and p = 0.028 in brainstem group) were both significantly improved after treatment in hemispheric and brainstem stroke patients. In hemispheric stroke patients, changes in FOIS were related to changes of functional brain connectivity in the ventral default mode network (vDMN) of the precuneus in brain functional MRI (fMRI). In brainstem stroke patients, changes in FOIS were related to changes of functional brain connectivity in the left sensorimotor network (LSMN) of the left postcentral region characterized by brain fMRI.

Conclusion: Both hemispheric and brainstem stroke patients with different swallowing difficulties showed improvements after swallowing training. For these two dysphagic stroke groups with corresponding etiologies, swallowing therapy could contribute to different functional neuroplasticity.

Early Screening Parameters for Dysphagia in Acute Ischemic Stroke

BACKGROUND

Dysphagia is a frequent symptom in patients with acute stroke. It is associated with malnutrition, aspiration and mortality. The identification of early screening parameters for dysphagia promptly leading to a professional swallowing examination is therefore of utmost importance. This study aimed to detect early and easily assessable predictors of dysphagia in a large cohort of patients with acute ischemic stroke.

METHODS

Our analysis was based on data from a prospective in-hospital registry. Patients with ischemic stroke were included over the course of 3 years. Patients were scheduled to undergo a clinical swallowing investigation within the first 24 h after hospital admission. Step-wise multivariate logistic regression was used to identify independent predictors of dysphagia in general and of pneumonia in particular.

RESULTS

1,646 patients with ischemic stroke were included. Stroke severity in terms of higher National Institute of Health Stroke Scale (NIHSS) values (p < 0.001), male gender (p = 0.006) and higher age (p < 0.001) independently predicted dysphagia. A receiver operating characteristics analysis revealed an NIHSS cut-off value of 4.5 for optimal differentiation between patients with and without dysphagia (sensitivity 0.77; specificity 0.77). Dysphagia (p < 0.001), male gender (p = 0.002), higher NIHSS scores (p < 0.001) and higher age (p = 0.002) were factors that were independently associated with pneumonia. The NIHSS cut-off value for differentiating between patients with and without pneumonia was 5.5 (sensitivity 0.91; specificity 0.67).

CONCLUSIONS

Stroke severity in terms of NIHSS is a simple and reliable predictor of dysphagia. Patients with NIHSS values ≥5 should be quickly directed towards a professional swallowing examination. Dysphagia was confirmed to be a strong predictor of pneumonia.

Functional changes of neural circuits in stroke patients with dysphagia: A meta-analysis

OBJECTIVE

Dysphagia is a common problem in stroke patients with unclear pathogenesis. Several recent functional magnetic resonance imaging (fMRI) studies had been carried out to explore the cerebral functional changes in dysphagic stroke patients. The aim of this study was to analysis these imaging findings using a meta-analysis.

METHODS

We used seed-based d mapping (SDM) to conduct a meta-analysis for dysphagic stroke patients prior to any kind of special treatment for dysphagia. A systematic search was conducted for the relevant studies. SDM meta-analysis method was used to examine regions of increased and decreased functional activation between dysphagic stroke patients and healthy controls.

RESULTS

Finally, six studies including 81 stroke patients with dysphagia and 78 healthy controls met the inclusion standards. When compared with healthy controls, stroke patients with dysphagia showed hyperactivation in left cingulate gyrus, left precentral gyrus and right posterior cingulate gyrus, and hypoactivation in right cuneus and left middle frontal gyrus.

CONCLUSIONS

The hyperactivity of precentral gyrus is crucial in stroke patients with dysphagia and may be associated with the severity of stroke. Besides the motor areas, the default-mode network regions (DMN) and affective network regions (AN) circuits are also involved in dysphagia after stroke.

Predictors of Dysphagia in Acute Pontine Infarction

Background and Purpose—

Little is known about the frequency and the clinical characteristics of neurogenic dysphagia in pontine strokes. In this study, we sought to identify predictors for dysphagia in a cohort of patients with isolated pontine infarctions.

Methods—

We included all patients admitted to our department between 2008 and 2014 having an acute (<48 hours after symptom onset) ischemic stroke in the pons, as documented by means of diffusion-weighted magnetic resonance imaging. Precise infarct localization was stratified according to established vascular territories. The presence of dysphagia was the primary end point of the study and was assessed by a Speech-Language Pathologist according to defined criteria.

Results—

The study recruited 59 patients, 14 with and 45 without dysphagia. Median (interquartile range) stroke severity (in terms of National Institutes of Health Stroke Scale values) was higher in the dysphagic group as compared with patients without dysphagia (8.5 [6–12] versus 2 [1–5]; P <0.001). Infarct localization in the upper part of the pons (78.6% versus 33.3%; P =0.004) and in the anterolateral vascular territory (78.6% versus 31.1%; P =0.002) occurred more often in the dysphagic group. In a multivariate model, age, infarct volume, and National Institutes of Health Stroke Scale value were independent predictors of dysphagia.

Conclusions—

Dysphagia occurs frequently in patients with isolated pontine infarctions. Clinical and imaging predictors of dysphagia may help to provide optimal screening, to prevent complications and to improve long-term prognosis.

A novel reflex cough testing device

Background

The reflex cough test is useful for detecting silent aspiration, a risk factor for aspiration pneumonia. However, assessing the risk of aspiration pneumonia requires measuring not only the cough reflex but also cough strength. Currently, no reflex cough testing device is available that can directly measure reflex cough strength. We therefore developed a new testing device that can easily and simultaneously measure cough strength and the time until the cough reflex, and verified whether screening with this new instrument is feasible for evaluating the risk of aspiration pneumonia.

Methods

This device consists of a special pipe with a double lumen, a nebulizer, and an electronic spirometer. We used a solution of prescription-grade L-tartaric acid to initiate the cough reflex. The solution was inhaled through a mouthpiece as a microaerosol produced by an ultrasonic nebulizer. The peak cough flow (PCF) of the induced cough was measured with the spirometer.

The 70 patients who participated in this study comprised 49 patients without a history of pneumonia (group A), 21 patients with a history of pneumonia (group B), and 10 healthy volunteers (control group).

Results

With the novel device, PCF and time until cough reflex could be measured without adverse effects. The PCF values were 118.3 ± 64.0 L/min, 47.7 ± 38.5 L/min, and 254.9 ± 83.8 L/min in group A, group B, and the control group, respectively. The PCF of group B was significantly lower than that of group A and the control group (p < 0.0001), while that of group B was significantly lower than that of the control group (p < 0.0001). The time until the cough reflex was 4.2 ± 5.9 s, 7.0 ± 7.0 s, and 1 s in group A, group B, and the control group, respectively. This duration was significantly longer for groups A and B than for the control group (A: p < 0.001, B: p < 0.001), but there was no significant difference between groups A and B (p = 0.0907).

Conclusion

Our newly developed device can easily and simultaneously measure the time until the cough reflex and the strength of involuntary coughs for assessment of patients at risk of aspiration pneumonia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-017-0365-y) contains supplementary material, which is available to authorized users.

Effects of Theta Burst Stimulation on Suprahyoid Motor Cortex Excitability in Healthy Subjects

BACKGROUND

Continuous theta burst stimulation (cTBS) and intermittent TBS (iTBS) are powerful patterns of repetitive transcranial magnetic stimulation (rTMS), with substantial potential for motor function rehabilitation post-stroke. However, TBS of suprahyoid motor cortex excitability has not been investigated. This study investigated TBS effects on suprahyoid motor cortex excitability and its potential mechanisms in healthy subjects.

METHODS

Thirty-five healthy subjects (23 females; mean age = 21.66 ± 1.66 years) completed three TBS protocols on separate days, separated by at least one week. A stereotaxic neuronavigation system facilitated accurate TMS positioning. Left and right suprahyoid motor evoked potentials (SMEP) were recorded using single-pulse TMS from the contralateral suprahyoid motor cortex before stimulation (baseline) and 0, 15, and 30 min after stimulation. The SMEP latency and amplitude were analyzed via repeated measures analysis of variance.

RESULTS

cTBS suppressed ipsilateral suprahyoid motor cortex excitability and activated the contralateral suprahyoid motor cortex. iTBS facilitated ipsilateral suprahyoid motor cortex excitability; however, it did not affect the contralateral excitability. iTBS eliminated the inhibitory effect caused by cTBS applied to the contralateral suprahyoid motor cortex. TBS had no significant effect on the latencies of bilateral SMEP. TBS effects on suprahyoid motor cortex excitability lasted a minimum of 30 min.

CONCLUSIONS

TBS effectively regulates suprahyoid motor cortex excitability. Suppression of excitability in one hemisphere leads to further activation of the corresponding contralateral motor cortex. iTBS reverses the inhibitory effect induced by cTBS of the contralateral suprahyoid motor cortex.

Dysphagia and aspiration as the only manifestations of a stroke

A 56-year-old patient was admitted to our hospital, presenting with dysphagia as the only symptom. He was very concerned about this difficulty in swallowing. Diseases of the upper digestive tract were suspected, but further investigations revealed a neurological disorder. He had suffered a brain stem stroke and, as a consequence, developed an aspiration pneumonia. What seemed a digestive disorder was indeed a brain stem stroke, therefore we had to deal with the diverse impacts of this condition.

Practical Assessment of Dysphagia in Stroke Patients

Objective

To develop a quantitative and organ-specific practical test for the diagnosis and treatment of dysphagia based on assessment of stroke patients.

Methods

An initial test composed of 24 items was designed to evaluate the function of the organs involved in swallowing. The grading system of the initial test was based on the analysis of 50 normal adults. The initial test was performed in 52 stroke patients with clinical symptoms of dysphagia. Aspiration was measured via a videofluoroscopic swallowing study (VFSS). The odds ratio was obtained to evaluate the correlation between each item in the initial test and the VFSS. A polychotomous linear logistic model was used to select the final test items.

Results

Eighteen of 24 initial items were selected as significant for the final tests. These 18 showed high initial validity and reliability. The Spearman correlation coefficient for the total score of the test and functional dysphagia scale was 0.96 (p<0.001), indicating a statistically significant positive correlation.

Conclusion

This study was carried out to design a quantitative and organ-specific test that assesses the causes of dysphagia in stroke patients; therefore, this test is considered very useful and highly applicable to the diagnosis and treatment of dysphagia.

Effectiveness of Chin-tuck Maneuver to Facilitate Swallowing in Neurologic Dysphagia

Introduction The chin-tuck maneuver is the most frequently employed postural maneuver in the treatment of neurogenic oropharyngeal dysphagia caused by encephalic vascular strokes and degenerative diseases.

Objective The purpose of this study was to investigate the effectiveness of this maneuver in patients with neurogenic dysphagia and factors that could interfere in it.

Methods In this retrospective cohort, we analyzed the medical files and videofluoroscopy exams of 35 patients (19 male – 54% and 16 female – 46%; age range between 20 and 89 years old; mean = 69 years).

Results The results suggest that the effectiveness of chin-tuck maneuver is related to the overall degree of dysphagia: the more severe the dysphagia, the less effective the maneuver.

Conclusion Chin-tuck maneuver should benefit dysphagic patients with delay in the swallowing trigger, reduced laryngeal elevation, and difficulties to swallow liquids, but is not the best compensatory strategy for patients with severe dysphagia.

Surgical treatment of bronchial asthma by resection of the laryngeal nerve

BACKGROUND

Management of asthma in chronically affected patients is a serious health problem. Our aim was to show that surgical treatment of chronic bronchial asthma by unilateral resection of the internal branch of the superior laryngeal nerve (ib-SLN) is an adequateand lasting remedial response.

PATIENTS AND METHODS

In a retrospective study, 41 (26 male and 15 female) patients with bronchial chronic asthma were treated surgically during the period between 2005 and 2013. It consisted of a unilateral resection of the ib-SLN under optical zoom, on patients placed in supinator position. 35 patients (24 male and 11 female) who were un-operated were included as a control.

RESULTS

In all patients, medication was reduced progressively. When the results were compared with the control group, it was seen that in 26% of the patients, both forced expiratory volume (FEV) and peak expiratory flow (PEF) increased significantly (p <05) and only modestly in 53.6% of patients (FEV, p <05 and PEF, p <05). In the remaining 20% of patients, these parameters remained however unchanged. Overall, in 80% of patients unilateral resection of the ib-SLN gave satisfactory results because it shortened the intervals and duration of asthmatic attacks, rendering thereby a reduction in medication.

CONCLUSION

This minimal-invasive method helped prevent/cure asphyxias in chronic bronchial asthma without affecting cough reflex,respiratory control and phonation and it helped patients avoid severe crisis. This approach is of interest for patients with severe and/or uncontrolled bronchial asthma in settings with limited access to drug treatment.

Electrophysiological association of spontaneous yawning and swallowing

Yawning and swallowing are fundamental physiological processes that are present from fetal stages throughout life and that involve sequential motor activities in the oropharyngo-larynx making it likely that they may share neuroanatomical pathways. We postulate that yawning and swallowing are controlled by a distributed network of brainstem regions including the central pattern generator of swallowing, and therefore spontaneous swallowing is frequently associated with spontaneous yawning. In this study, we sought to test this hypothesis by evaluating the elementary features of yawning in the facial, masseter and submental muscles, together with laryngeal movement sensor and respiratory recordings for spontaneous swallowing. We investigated 15 healthy, normal control subjects, 10 patients with Parkinson's disease (PD) and 10 patients with brainstem stroke (BSS). Apart from four subjects with PD and two with BSS, who had dysphagia, none of the other study subjects were dysphagic by published criteria. Twenty-five subjects (10 control, 10 BSS, 5 PD) were evaluated by 1-h polygraphic recording, and 10 (5 control, 5 PD) underwent whole-night sleep recordings. One hundred thirty-two yawns were collected, 113 of which were associated with spontaneous swallows, a clear excess of what would be considered as coincidence. The yawns related with swallows could be classified into the following three categories. The characteristics or the duration of swallows and yawns were similar between controls and disease subjects, with the exception of increased duration of yawning in subjects with BSS. Our findings support the presence of common neuroanatomico-physiological pathways for spontaneous swallows and yawning.

Functional mitochondrial analysis in acute brain sections from adult rats reveals mitochondrial dysfunction in a rat model of migraine

Mitochondrial dysfunction has been implicated in many neurological disorders that only develop or are much more severe in adults, yet no methodology exists that allows for medium-throughput functional mitochondrial analysis of brain sections from adult animals. We developed a technique for quantifying mitochondrial respiration in acutely isolated adult rat brain sections with the Seahorse XF Analyzer. Evaluating a range of conditions made quantifying mitochondrial function from acutely derived adult brain sections from the cortex, cerebellum, and trigeminal nucleus caudalis possible. Optimization of this technique demonstrated that the ideal section size was 1 mm wide. We found that sectioning brains at physiological temperatures was necessary for consistent metabolic analysis of trigeminal nucleus caudalis sections. Oxygen consumption in these sections was highly coupled to ATP synthesis, had robust spare respiratory capacities, and had limited nonmitochondrial respiration, all indicative of healthy tissue. We demonstrate the effectiveness of this technique by identifying a decreased spare respiratory capacity in the trigeminal nucleus caudalis of a rat model of chronic migraine, a neurological disorder that has been associated with mitochondrial dysfunction. This technique allows for 24 acutely isolated sections from multiple brain regions of a single adult rat to be analyzed simultaneously with four sequential drug treatments, greatly advancing the ability to study mitochondrial physiology in adult neurological disorders.

Gastrointestinal complications after ischemic stroke

Ischemic stroke is an important cause of morbidity and mortality, and currently the leading cause of adult disability in developed countries. Stroke is associated with various non-neurological medical complications, including infections and thrombosis. Gastrointestinal complications after stroke are also common, with over half of all stroke patients presenting with dysphagia, constipation, fecal incontinence or gastrointestinal bleeding. These complications are associated with increased hospital length of stay, the development of further complications and even increased mortality. In this article we review the epidemiology, pathophysiology, diagnosis, management and prevention of the most common gastrointestinal complications associated with ischemic stroke.

Association between pharyngeal residue and posterior oral spillage with penetration and aspiration in stroke

PURPOSE

This study aimed at showing association between the posterior oral spillage and pharyngeal residue with tracheal aspiration and/or laryngeal penetration in stroke.

METHODS

Clinical cross-sectional retrospective multicenter study. The study included 63 videofluoroscopic tests of post-ischemic stroke individuals and oropharyngeal dysphagia data of the three reference centers providing care for patients with dysphagia (43 men and 20 women; age range: from 40 to 90 years). These individuals were divided into two groups. Group I consisted of 35 participants with the presence of penetration and/or laryngotracheal aspiration, and Group II consisted of 28 individuals with no penetration and/or aspiration. Videofluoroscopic swallowing test results were analyzed to divide the groups, and the presence of posterior oral spillage and pharyngeal residue was observed.

RESULTS

No association was found between the groups with posterior oral spillage (χ²=1.65; p=0.30; φ²=0.02), but there was statistical difference for the association between pharyngeal residue (χ²=12.86; p=0.003; φ²=0.20) and the groups.

CONCLUSION

There is an association between pharyngeal residue and penetration with tracheal aspiration in post-stroke individuals.

Associating factors regarding nasogastric tube removal in patients with Dysphagia after stroke

Objective

To demonstrate associating factors regarding nasogastric tube (NGT) removal in patients with dysphagia after stroke.

Methods

This study is a retrospective medical chart review. Patients were divided into non-brain stem (NBS) and brain stem (BS) groups. A videofluoroscopic swallowing study was conducted until swallowing functions were recovered. Initial disease status was measured using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Risk factors related to stroke were evaluated. The penetration-aspiration scale (PAS) was used as the swallowing test. Functional status was measured by Mini-Mental Status Examination (MMSE) and Modified Barthel Index (MBI). Within each group, initial evaluations and their subsequent changes were compared according to the NGT removal status. Correlation between the NGT removal time and other initial factors were evaluated.

Results

Ninety-nine patients were allocated to the NBS group and 39 to the BS group. In NBS, age, PAS, MMSE, and MBI were significantly different according to the NGT removal status. In BS, smoking and PAS were significantly different. In NBS, changes in PAS, MMSE, and MBI were significantly different according to the NGT removal status. In BS, only PAS change was significantly different. In NBS, initial NIHSS, mRS, MMSE, and MBI were correlated with removal time.

Conclusion

In stroke patients with NTG, younger age, better initial disease and functional status seems to remove NGT in NBS stroke. Therefore, when deciding to remove NGT, those three factors should be considered discreetly.

Lesion Location Predicts Transient and Extended Risk of Aspiration After Supratentorial Ischemic Stroke

Background and Purpose—

To assess the association of lesion location and risk of aspiration and to establish predictors of transient versus extended risk of aspiration after supratentorial ischemic stroke.

Methods—

Atlas-based localization analysis was performed in consecutive patients with MRI-proven first-time acute supratentorial ischemic stroke. Standardized swallowing assessment was carried out within 8±18 hours and 7.8±1.2 days after admission.

Results—

In a prospective, longitudinal analysis, 34 of 94 patients (36%) were classified as having acute risk of aspiration, which was extended (≥7 days) or transient (<7 days) in 17 cases. There were no between-group differences in age, sex, cause of stroke, risk factors, prestroke disability, lesion side, or the degree of age-related white-matter changes. Correcting for stroke volume and National Institutes of Health Stroke Scale with a multiple logistic regression model, significant adjusted odds ratios in favor of acute risk of aspiration were demonstrated for the internal capsule (adjusted odds ratio, 6.2; P <0.002) and the insular cortex (adjusted odds ratio, 4.8; P <0.003). In a multivariate model of extended versus transient risk of aspiration, combined lesions of the frontal operculum and insular cortex was the only significant independent predictor of poor recovery (adjusted odds ratio, 33.8; P <0.008).

Conclusions—

Lesions of the insular cortex and the internal capsule are significantly associated with acute risk of aspiration after stroke. Combined ischemic infarctions of the frontal operculum and the insular cortex are likely to cause extended risk of aspiration in stroke patients, whereas risk of aspiration tends to be transient in subcortical stroke.

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.

The relationship between residue and aspiration on the subsequent swallow: an application of the normalized residue ratio scale

Postswallow residue is widely considered to be a sign of swallowing impairment and is assumed to pose risk for aspiration on subsequent swallows. We undertook a preliminary retrospective study to investigate the link between postswallow residue and penetration-aspiration on the immediately occurring subsequent clearing swallow (i.e., without introduction of a new bolus). Videofluoroscopy clips for 156 thin-liquid single bolus swallows by patients with neurogenic dysphagia were selected for study because they displayed multiple swallows per bolus. Residue for each subswallow (n = 407) was analyzed using the Normalized Residue Ratio Scale for the valleculae (NRRSv) and piriform sinuses. The association between residue presence at the end of a swallow and penetration-aspiration on the next swallow was examined. Postswallow residue in one or both pharyngeal spaces was significantly associated with impaired swallowing safety on the subsequent clearing swallow for the same bolus. However, when analyzed separately by residue location, only vallecular residue was significantly associated with impaired swallowing safety on the next clearing swallow. The distribution of NRRSv scores by swallowing safety demonstrated an NRRSv cut-point of 0.09, above which there was a 2.07 times greater relative risk of penetration-aspiration. Postswallow vallecular residue, measured using the NRRS, is significantly associated with penetration-aspiration on subsequent clearing swallows. A clinically meaningful cut-point of 0.09 on the NRRSv scale demarcates this risk. Further research with different bolus consistencies is needed.