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Cerebellar brain inhibition (CBI), a neural connection between the cerebellum and primary motor cortex (M1), has been researched as a target pathway for neuromodulation to improve clinical outcomes in various neurological diseases. However, conflicting results of anodal cerebellar transcranial direct current stimulation (acb-tDCS) on M1 excitability indicate that additional investigation is required to examine its precise effect. This study aimed to gather evidence of the neuromodulatory effect of acb-tDCS on the M1 using functional near-infrared spectroscopy (fNIRS). Sixteen healthy participants were included in this cross-over study. Participants received real and sham acb-tDCS randomly, with a minimum 1-week washout period between them. The anode and cathode were placed on the right cerebellum and the right buccinator muscle, respectively. Stimulation lasted 20 min at an intensity of 2 mA, and fNIRS data were recorded for 42 min (including a 4-min baseline before stimulation and an 18-min post-stimulation duration) using eight channels attached bilaterally on the M1. acb-tDCS induced a significant decrease in oxyhemoglobin (HbO) concentration (inhibitory effect) in the left (contralateral) M1, whereas it induced a significant increase in HbO concentration (excitatory effect) in the right (ipsilateral) M1 compared to sham tDCS during (p < 0.05) and after stimulation (p < 0.01) in a group level analysis. At the individual level, variations in response to acb-tDCS were observed. Our findings demonstrate the neuromodulatory effects of acb-tDCS on the bilateral M1 in terms of neuronal hemodynamics. [ABSTRACT FROM AUTHOR]

We investigated the activation pattern of the motor cortex (M1) and parietal cortex during immersive virtual reality (VR)-based mirror visual feedback (MVF) of the upper limb in 14 patients with chronic stroke and severe upper limb hemiparesis and in 21 healthy controls. Participants performed wrist extension with unaffected wrists (dominant side in controls). In the MVF condition, movement of the affected hand was synchronized with that of the unaffected hand. In the no-MVF condition, only the movement of unaffected hand was shown. Mu suppression in bilateral M1 and parietal cortex and mu coherence were analyzed. In patients with stroke, MVF induced significant mu suppression in both the ipsilesional M1 and parietal lobes (p = 0.006 and p = 0.009, respectively), while mu suppression was observed in the bilateral M1 (p = 0.003 for ipsilesional and p = 0.041 for contralesional M1, respectively) and contralesional parietal lobes in the controls (p = 0.036). The ipsilesional mu coherence between the M1 and parietal cortex in patients with stroke was stronger than controls, regardless of MVF condition (p < 0.001), while mu coherence between interhemispheric M1 cortices was significantly weaker in patients with stroke (p = 0.032). Our findings provide evidence of the neural mechanism of MVF using immersive VR in patients with stroke. [ABSTRACT FROM AUTHOR]

Purpose: Most previous reports on dysphagia in cancer have focused on specific cancer types, particularly head and neck cancer. Therefore, we aimed to investigate the incidence of dysphagia in patients with various cancers using a nationwide database in South Korea. Methods: This was a retrospective cohort study using the National Health Insurance Service database. Claim codes were used for the selection criteria and operational definitions. The total population data from 2010 to 2015 were extracted. The crude incidence of dysphagia was calculated per 1,000 person-years. The multivariate adjusted Cox proportional hazards regression was used to determine the effects of different cancers on the incidence of dysphagia. Results: People with cancer had a lower income and suffered from a higher risk of comorbidities compared to people without cancer. The risk of dysphagia increased in all types of cancers, particularly in the oral cavity and pharynx (hazard ratio [HR]: 20.65, 95% confidence interval [CI]: 17.73–24.06), esophagus (HR: 18.25, 95% CI: 15.66–21.26), larynx (HR: 12.87, 95% CI: 10.33–16.02), and central nervous system (HR: 12.42, 95% CI: 10.33–14.94). Conclusions: The risk of dysphagia was significantly higher in the cancer group than in the non-cancer group. As the survival of cancer patients is improving with the development of new treatments, more attention should be paid to dysphagia in the management of cancer. Prompt and appropriate multidisciplinary interventions for dysphagia are necessary to improve the recovery and quality of life in cancer patients. [ABSTRACT FROM AUTHOR]

Electromechanical-assisted gait training may be an effective intervention to promote motor recovery after brain injury. However, many studies still have difficulties in clarifying the difference between electromechanical-assisted gait training and conventional gait training. To evaluate the effectiveness of electromechanical-assisted gait training compared to that of conventional gait training on clinical walking function and gait symmetry of stroke patients. We randomly assigned patients with stroke (n = 144) to a control group (physical therapist-assisted gait training) and an experimental group (electromechanical gait training). Both types of gait training were done for 30 min each day, 5 days a week for 4 weeks. The primary endpoint was the change in functional ambulatory category (FAC). Secondary endpoints were clinical walking functions and gait symmetries of swing time and step length. All outcomes were measured at baseline (pre-intervention) and at 4 weeks after the baseline (post-intervention). FAC showed significant improvement after the intervention, as did clinical walking functions, in both groups. The step-length asymmetry improved in the control group, but that in the experimental group and the swing-time asymmetry in both groups did not show significant improvement. In the subgroup analysis of stroke duration of 90 days, FAC and clinical walking functions showed more significant improvement in the subacute group than in the chronic group. However, gait symmetries did not show any significant changes in either the subacute or the chronic group. Electromechanically assisted gait training by EXOWALK was as effective as conventional gait training with a physiotherapist. Although clinical walking function in the subacute group improved more than in the chronic group, gait asymmetry did not improve for either group after gait training. Trial registration: KCT0003411 Clinical Research Information Service (CRIS), Republic of Korea. [ABSTRACT FROM AUTHOR]

Prism Adaptation (PA) is used to alleviate spatial neglect. We combined immersive virtual reality with a depth-sensing camera to develop virtual prism adaptation therapy (VPAT), which block external visual cues and easily quantify and monitor errors than conventional PA. We conducted a feasibility study to investigate whether VPAT can induce behavioral adaptations by measuring after-effect and identifying which cortical areas were most significantly activated during VPAT using functional near-infrared spectroscopy (fNIRS). Fourteen healthy subjects participated in this study. The experiment consisted of four sequential phases (pre-VPAT, VPAT-10°, VPAT-20°, and post-VPAT). To compare the most significantly activated cortical areas during pointing in different phases against pointing during the pre-VPAT phase, we analyzed changes in oxyhemoglobin concentration using fNIRS during pointing. The pointing errors of the virtual hand deviated to the right-side during early pointing blocks in the VPAT-10° and VPAT-20° phases. There was a left-side deviation of the real hand to the target in the post-VPAT phase, demonstrating after-effect. The most significantly activated channels during pointing tasks were located in the right hemisphere, and possible corresponding cortical areas included the dorsolateral prefrontal cortex and frontal eye field. In conclusion, VPAT may induce behavioral adaptation with modulation of the dorsal attentional network. [ABSTRACT FROM AUTHOR]

Dysphagia is common in older adults and associated with increased socioeconomic burdens. Recently, sarcopenia is considered to be a possible contributor for dysphagia. The purpose of this study is to investigate the association of dysphagia with sarcopenia in a geriatric population in Korea. This is a cross-sectional study using data from the Korean Longitudinal Study on Health and Aging (KLoSHA). Community-dwelling men and women aged 65 years and older without common causes of dysphagia in Seongnam City, Korea were included (N = 236). Dysphagia was screened using Standardized Swallowing Assessment. Appendicular skeletal muscle mass was calculated by dual-energy X-ray absorptiometry. Grip strength and long-distance corridor walk were assessed. Of 236 subjects, 54 (22.9%) showed dysphagia and 38 (16.1%) showed sarcopenia. Fourteen (5.9%) participants were diagnosed with sarcopenic dysphagia. In multiple logistic regression analysis for dysphagia, sarcopenia was the only significant variable with odds ratio of 2.738 (95% confidence interval 1.160-6.466). Sarcopenia was associated with increased risk of dysphagia in community-dwelling older adults having no common causes of dysphagia even after adjusting for possible confounders. A prospective study with a larger sample size is needed to reveal their causal relationship in the future. [ABSTRACT FROM AUTHOR]

Conventional kinematic analysis of videofluoroscopic (VF) swallowing image, most popular for dysphagia diagnosis, requires time-consuming and repetitive manual extraction of diagnostic information from multiple images representing one swallowing period, which results in a heavy work load for clinicians and excessive hospital visits for patients to receive counseling and prescriptions. In this study, a software platform was developed that can assist in the VF diagnosis of dysphagia by automatically extracting a two-dimensional moving trajectory of the hyoid bone as well as 11 temporal and kinematic parameters. Fifty VF swallowing videos containing both non-mandible-overlapped and mandible-overlapped cases from eight patients with dysphagia of various etiologies and 19 videos from ten healthy controls were utilized for performance verification. Percent errors of hyoid bone tracking were 1.7 ± 2.1% for non-overlapped images and 4.2 ± 4.8% for overlapped images. Correlation coefficients between manually extracted and automatically extracted moving trajectories of the hyoid bone were 0.986 ± 0.017 (X-axis) and 0.992 ± 0.006 (Y-axis) for non-overlapped images, and 0.988 ± 0.009 (X-axis) and 0.991 ± 0.006 (Y-axis) for overlapped images. Based on the experimental results, we believe that the proposed platform has the potential to improve the satisfaction of both clinicians and patients with dysphagia. [ABSTRACT FROM AUTHOR]

Background and Purpose: Intravenous (IV) thrombolysis with recombinant tissue plasminogen activator (rt-PA) has demonstrated favorable clinical outcomes in a 3-6 h window in patients selected with perfusion/diffusion mismatch. However, the advantages of combined IV and intraarterial (IA) thrombolysis after 3 h of stroke onset are unexplored.Methods: Acute ischemic stroke patients with persistent occlusion of intracranial large arteries were screened prospectively for thrombolysis by evaluating perfusion/diffusion mismatch on MRI. The IV rt-PA was initiated within 3-6 h, and additional urokinase (UK) was then administered via the IA route after angiography.Results: Four patients had middle cerebral artery occlusion and one patient had an internal carotid artery occlusion. The median time from the symptom onset to the initiation of IV therapy and to the initiation of IA treatment was 215 +/- 30 min and 292 +/- 41 min, respectively. The median National Institutes of Health Stroke Scale (NIHSS) scores were as follows: initial, 13; immediately after IA treatment, 8; at 24 h, 5; and at 7 days, 3. The Thrombolysis in Myocardial Infarction (TIMI) score after the completion of thrombolysis was 2-3. Four patients without intracerebral hemorrhage recovered completely or exhibited mild disability and one patient with hemorrhage also demonstrated a favorable outcome.Conclusion: This preliminary result suggests that if a significant perfusion/diffusion mismatch on MRI is identified, a sequential combination thrombolysis of IV rt-PA and IA UK is potentially beneficial in moderate to severe acute ischemic stroke patients who are treated within 3-6 h after symptom onset. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify the videofluoroscopic prognostic factors that affect the recovery of swallowing function at an early stage after stroke and to make a tool for predicting the long-term prognosis. Eighty-three poststroke patients were selected prospectively. These patients had all undergone videofluoroscopic swallowing studies at an average of 40 days after stroke onset and were followed up for over six months. Prognostic factors were determined by logistic regression analysis between the baseline videofluoroscopic findings and aspiration over six months ( p < 0.05). A videofluoroscopic dysphagia scale (VDS) with a sum of 100 was made according to the odds ratios of prognostic factors. The validity of the scale was evaluated by using a receiver operating characteristic curve. The VDS was compiled using the following 14 items: lip closure, bolus formation, mastication, apraxia, tongue-to-palate contact, premature bolus loss, oral transit time, triggering of pharyngeal swallow, vallecular residue, laryngeal elevation, pyriform sinus residue, coating of pharyngeal wall, pharyngeal transit time, and aspiration. At a scale cutoff value of 47, the sensitivity was 0.91 and the specificity was 0.92. The VDS was developed to be used as an objective and quantifiable predictor of long-term persistent dysphagia after stroke. [ABSTRACT FROM AUTHOR]