Takamichi Tohyama

OBJECTIVE: This study aimed to examine the effects of galvanic vestibular stimulation (GVS) on visual vertical cognition and sitting balance in stroke patients. MATERIALS AND METHODS: Patients with unilateral supratentorial infarction and hemorrhagic lesions and healthy controls were recruited. Bipolar GVS was performed through the bilateral mastoid processes with an 1.5-mA electric current. Each participant received three stimulation patterns: right anode-left cathode, left anode-right cathode, and sham. The subjective visual vertical (SVV) and center of gravity positions in the sitting posture were measured in three groups of participants: patients with right hemisphere lesions, patients with left hemisphere lesions, and in healthy controls. Changes in the SVV and center of gravity positions before and during galvanic vestibular stimulation were assessed. RESULTS: In each group, eight individuals were recruited for SVV measurements and nine individuals for center of gravity measurements. We found changes due to polarity of stimulation on the SVV and mediolateral changes in the center of gravity in the sitting position of patients with stroke, while there was no significant difference between groups or interaction of the two factors (polarity vs. group). CONCLUSION: Changes in the visual vertical cognition and sitting balance occur during GVS in patients with stroke. GVS is a potential tool for ameliorating balance dysfunction in patients with stroke.

OBJECTIVE: To compare the functional outcomes of patients with lower limb amputations receiving haemodialysis and those not receiving haemodialysis. DESIGN: A retrospective cohort study. PATIENTS: Patients with lower limb amputation who were admitted to a convalescent rehabilitation ward between January 2018 and December 2021. METHODS: The primary outcome was the effectiveness of the Functional Independence Measure (FIM) during hospitalisation in the ward. Secondary outcomes included the total and subtotal (motor/cognitive) FIM scores at discharge, gain in the total and subtotal (motor/cognitive) FIM scores, K-level at discharge, length of hospital stay in the ward, rehabilitation time, and discharge destination. Outcomes were compared between the non-haemodialysis and haemodialysis groups. RESULTS: A total of 28 patients (mean [standard deviation] age, 67.0 [11.9] years; men, 20) were enrolled in this study. Among them, 11 patients underwent haemodialysis. The FIM effectiveness was significantly higher in the non-haemodialysis group than in the haemodialysis group (median [interquartile range], 0.78 [0.72 - 0.81] vs 0.65 [0.28 - 0.75], p = 0.038). The amount of rehabilitation and all secondary outcomes were not significantly different between the groups (p > 0.05). CONCLUSION: Patients with lower limb amputation who were receiving haemodialysis had poorer FIM effectiveness than those not receiving haemodialysis.

Recently, surface electroencephalogram (EEG)-based brain-machine interfaces (BMI) have been used for people with disabilities. As a BMI signal source, event-related desynchronization of alpha-band EEG (8-13 Hz) during motor imagery (mu ERD), which is interpreted as desynchronized activities of the activated neurons, is commonly used. However, it is often difficult for patients with severe hemiparesis to produce mu ERD of sufficient strength to activate BMI. Therefore, whether it is possible to modulate mu ERD during motor imagery with anodal transcranial direct-current stimulation (tDCS) was assessed in a severe left hemiparetic stroke patient. EEG was recorded over the primary motor cortex (M1), and mu ERD during finger flexion imagery was measured before and after a 5-day course of tDCS applied to M1. The ERD recorded over the affected M1 increased significantly after tDCS intervention. Anodal tDCS may increase motor cortex excitability and potentiate ERD during motor imagery in patients with severe hemiparetic stroke. © 2011 by The Keio Journal of Medicine.