Tetsuya Tsuji

Identification of a simple screening tool for dysphagia in patients with stroke using factor analysis of multiple dysphagia variables

OBJECTIVE To identify a most useful and simple clinical screening tool to predict videofluoroscopic aspiration in patients with stroke. DESIGN Factor analysis of multiple dysphagia variables and sensitivity and specificity testing with chi-square test. PATIENTS Sixty-one consecutive stroke patients with symptoms suggestive of dysphagia admitted to a university hospital and its 4 affiliated hospitals in Japan. METHODS Factors were extracted from 6 oromotor examinations (lip closure, tongue movement, palatal elevation, gag reflex, voice quality and motor speech function), 2 swallow screen tests (saliva swallowing test and our modified water swallowing test using 30 ml of water) and 4 parameters evaluated with a videofluoroscopic swallow study. Sensitivity and specificity of each dysphagia-related variable was determined against aspiration in a videofluoroscopic swallow study. RESULTS Factor analysis revealed that cough/voice change in the water swallowing test and aspiration on videofluoroscopic swallow study belonged to the same factor. Chi-square analysis showed that cough/voice change in the water swallowing test was the only variable that was significantly associated with aspiration on videofluoroscopic swallow study, with a sensitivity of 72% (95% CI: 61-83%) and a specificity of 67% (CI: 55-79%) as a predictor of aspiration (p<0.05). CONCLUSION We recommend our modified 30 ml water-swallowing test as a useful single task-screening tool to detect aspiration.

Long lasting effects of rTMS and associated peripheral sensory input on MEPs, SEPs and transcortical reflex excitability in humans

We tested the effect of repetitive transcranial magnetic stimulation (rTMS) over the motor cortex on the size of transcortical stretch and mixed nerve reflexes. Fourteen healthy subjects were investigated using either 25 min of 1 Hz rTMS or 30 min of 0.1 Hz rTMS paired with electrical stimulation of the motor point of the first dorsal interosseous muscle (FDI). Following treatment, we measured the effect on the size of: (1) EMG responses evoked in FDI by transcranial magnetic stimulation (MEPs), (2) somatosensory evoked potentials (SEPs) evoked by ulnar nerve stimulation, and (3) transcortical stretch or electrically elicited reflexes. rTMS at 1 Hz reduced the amplitude of both MEPs and long latency reflexes by 20–30 % for about 10 min after the end of stimulation. Short latency reflexes were unaffected. SEPs were not studied, as it has been shown previously that they are also suppressed. rTMS at 0.1 Hz paired with motor point stimulation (interstimulus interval of 25 ms) increased the amplitude of the MEP and the cortical components of the SEP (N20/P25 and later peaks) for up to 10 min. Long latency reflexes were facilitated with the same time course. We conclude that rTMS over the motor cortex either alone or in conjunction with peripheral inputs can decrease or increase the excitability of the sensory and motor cortex for short periods after the end of stimulation. These changes affect not only MEPs and SEPs but also EMG responses to more ‘natural’ inputs involved in transcortical stretch reflexes.

Prism adaptation therapy enhances rehabilitation of stroke patients with unilateral spatial neglect: a randomized, controlled trial.

Background and objective. Unilateral spatial neglect (USN) can interfere with rehabilitation processes and lead to poor functional outcome. The purpose of this study was to determine whether prism adaptation (PA) therapy improves USN and functional outcomes in stroke patients in the subacute stage. Methods. A multicenter, double-masked, randomized, controlled trial was conducted to evaluate the effects of a 2-week PA therapy on USN assessed with the Behavioral Inattention Test (BIT), the Catherine Bergego Scale (CBS), and activities of daily living (ADL) as evaluated with the Functional Independence Measure (FIM). A total of 38 USN patients with right-brain damage were divided into prism (n = 20) and control (n = 18) groups. Patients were divided into mild and severe USN groups according to BIT behavioral test (mild ≥ 55 and severe<55). The prism group performed repetitive pointing with prism glasses that induce rightward optical shift twice daily, 5 days per week, for 2 weeks, whereas the control group performed similar pointing training with neutral glasses. Results. The FIM improved significantly more in the prism group. In mild USN patients, there was significantly greater improvement of BIT and FIM in the prism group. Conclusions. PA therapy can significantly improve ADL in patients with subacute stroke.

Motor Improvement and Corticospinal Modulation Induced by Hybrid Assistive Neuromuscular Dynamic Stimulation (HANDS) Therapy in Patients With Chronic Stroke

Background and objective . We devised a therapeutic approach to facilitate the use of the hemiparetic upper extremity (UE) in daily life by combining integrated volitional control electrical stimulation with a wrist splint, called hybrid assistive neuromuscular dynamic stimulation (HANDS). Methods. Twenty patients with chronic hemiparetic stroke (median 17.5 months) had moderate to severe UE weakness. Before and immediately after completing 3 weeks of training in 40-minute sessions, 5 days per week over 3 weeks and wearing the system for 8 hours each day, clinical measures of motor impairment, spasticity, and UE functional scores, as well as neurophysiological measures including electromyography activity, reciprocal inhibition, and intracortical inhibition were assessed. A follow-up clinical assessment was performed 3 months later. Results. UE motor function, spasticity, and functional scores improved after the intervention. Neurophysiologically, the intervention induced restoration of presynaptic and long loop inhibitory connections as well as disynaptic reciprocal inhibition. Paired pulse transcranial magnetic stimulation study indicated disinhibition of the short intracortical inhibition in the affected hemisphere. The follow-up assessment showed that improved UE functions were maintained at 3 months. Conclusion. The combination of hand splint and volitional and electrically induced muscle contraction can induce corticospinal plasticity and may offer a promising option for the management of the paretic UE in patients with stroke. A larger sample size with randomized controls is needed to demonstrate effectiveness.

ADL structure for stroke patients in Japan based on the functional independence measure

Tsuji T, Sonoda S, Domen K, Saitoh E, Liu M, Chino N: ADL structure for stroke patients in Japan based on the Functional Independence Measure. Am J Phys Med Rehabil 1995;74:432—438 The difficulty patterns of FIM (Functional Independence Measure) in Japan were determined and compared with patterns found in the United States to assess whether FIM can be used for worldwide comparisons of ADL (the activities of daily living). The FIM was measured for 190 stroke patients in several hospitals throughout Japan. The scores at admission and discharge were converted to an interval scale by Rasch analysis. Right and left brain lesion patients were analyzed separately. The FIM items were divided into two groups: motor items and cognitive items to minimize misfit. A degree of misfit was acceptable, except for bowel and bladder management, stairs, bathing, and expression. Motor items, eating, and bowel and bladder management were the easiest; stairs, bathing, and tub/shower transfers were the most difficult. The difficulty patterns of patients with left and right hemisphere lesions were almost identical. Bathing and tub/shower transfer were more difficult for Japanese patients than for those studied in the United States. Concerning the cognitive items, expression was easiest for patients with right hemisphere lesions but most difficult for those with left hemisphere lesions. Social interaction was easier for Japanese patients with left hemisphere lesions than the other patients. The item difficulty patterns in Japan differs slightly from those in the United States because of cultural differences. As countries show different patterns of difficulty, we must be careful when making international comparisons of FIM data converted by Rasch analysis.

Osteoporosis in hemiplegic stroke patients as studied with dual-energy x-ray absorptiometry

OBJECTIVES To compare bone mineral densities (BMDs) of the affected and unaffected limbs in stroke patients at multiple sites; to study longitudinal changes during a 3-month rehabilitation program; and to relate BMDs to demographic, impairment, and disability variables. DESIGN Descriptive study. SETTING Tertiary rehabilitation center. PATIENTS One hundred four consecutive hemiplegic inpatients, 69 men, age 56.5 +/- 13.2 yrs, 47 with left-sided brain lesion. Median days from onset to admission and median length of stay days were 83 and 105.5, respectively. MAIN OUTCOME MEASURES BMDs of proximal humerus, distal radius, femoral neck, and calcaneus bilaterally, and third lumbar vertebra, measured with dual-energy x-ray absorptiometry (DXA), were compared between affected and unaffected sides at admission and discharge. RESULTS Stroke Impairment Assessment Set (SIAS) motor scores, Functional Independence Measure (FIM) scores, grip strength, and awake/sleep heart rate counts (activity index) improved significantly at discharge. Affected/unaffected BMD ratios were 88.3% to 98.4% at admission and 79.6% to 98.8% at discharge, lowest for the humerus. Discharge/admission ratios were 89.1% to 97.8% for the affected and 97.4% to 100% for the unaffected side. All BMDs were intercorrelated (R = .438 to .873). They correlated significantly with age, body weight, grip strength, FIM scores, and activity index. Factors selected to explain BMD with multiple regression analysis differed according to the site and timing of the measurement. CONCLUSIONS BMDs of the affected side were lower and most marked in the humerus. Longitudinally, not only the affected but the unaffected BMDs decreased. Age, sex, duration of stroke, anthropometric measurements, motor paralysis, muscle strength, and activity level contributed differently to bone loss according to the site and timing of the measurement.

Comorbidities in stroke patients as assessed with a newly developed comorbidity scale

We previously reported reliability and validity of our newly developed comorbidity scale (CS) for stroke outcome research based on a retrospective sample. The objectives of this study were to cross-validate the comorbidity scale in a new prospective sample and to investigate longitudinal changes of the comorbidity scale during hospitalization. In a prospective sample of 175 stroke patients admitted to five nonacute rehabilitation hospitals in Japan, we analyzed the frequency and grading of comorbidities and compared the comorbidity scale with demographic data, impairment as assessed with the Stroke Impairment Assessment Set (SIAS), and disability as measured with the Functional Independence Measure (FIM(SM)). The results were compared with our previous retrospective study. We also studied longitudinal changes by measuring the comorbidity scale on admission, 2 wk later, and at discharge of 67 patients. As a result, the comorbidity scaling was significantly lower in the prospective sample, and it increased at the second measurement and then plateaued. Among the comorbidities, hypertension ranked first, followed by shoulder pain, and diabetes mellitus. Similar to our previous retrospective study, the comorbidity scale correlated positively with age and length of stay and correlated negatively with the SIAS motor item scores and the FIM scores. In conclusion, the present study suggested concurrent and predictive validity of the comorbidity scale in a prospective sample as well and clarified the comorbidity characteristics of stroke inpatients.

Comparison of the After-Effects of Transcranial Direct Current Stimulation Over the Motor Cortex in Patients With Stroke and Healthy Volunteers

ABSTRACT It is known that weak transcranial direct current stimulation (tDCS) induces persistent excitability changes in the cerebral cortex. There are, however, few studies that compare the after-effects of anodal versus cathodal tDCS in patients with stroke. This study assessed the after-effects of tDCS over the motor cortex in patients with hemiparetic stroke and healthy volunteers. Seven stroke patients and nine healthy volunteers were recruited. Ten minutes of anodal and cathodal tDCS (1 mA) and sham stimulation were applied to the affected primary motor cortex (M1) on different days. In healthy subjects, tDCS was applied to the right M1. Before and after tDCS, motor-evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle and silent period were measured. Anodal tDCS increased the MEPs of the affected FDI in patients with stroke as well as in healthy subjects. Cathodal tDCS increased the MEPs of the affected FDI in patients with stroke. In healthy subjects, however, cathodal tDCS decreased the MEPs. We found no significant change in the duration of the silent period after anodal or cathodal tDCS. We found that both anodal and cathodal tDCS increased the affected M1 excitability in patients with stroke. It is thought that the after-effects of tDCS are different in patients with stroke compared with healthy subjects.

Development of a new measure to assess trunk impairment after stroke (trunk impairment scale): its psychometric properties.

Fujiwara T, Liu M, Tsuji T, Sonoda S, Mizuno K, Akaboshi K, Hase K, Masakado Y, Chino N: Development of a new measure to assess trunk impairment after stroke (Trunk Impairment Scale): Its psychometric properties. Am J Phys Med Rehabil 2004;83:681–688. Objective:The purpose of this study was to investigate reliability, validity, internal structure, and responsiveness of our newly developed Trunk Impairment Scale (TIS) for patients with stroke. Design:A total of 73 patients with stroke participated in this prospective study. Interrater reliability (weighted kappa statistics), content validity (principal component analysis), concurrent validity (Spearmans rank correlation with the Trunk Control Test), predictive validity (prediction of discharge FIM™ scores), and responsiveness (standardized response mean values) were examined. Internal consistency and item difficulties were analyzed with Rasch analysis. Results:The weighted kappa of each TIS item ranged from 0.66 to 1.0. Principal component analysis revealed that the TIS measured a domain similar to the Stroke Impairment Assessment Set trunk items but different from the Stroke Impairment Assessment Set motor and visuospatial items. The TIS correlated with the Trunk Control Test (r = 0.91). To predict discharge FIM motor scores, addition of the TIS as one of the predictors to age, time from onset, and admission FIM score increased the adjusted R2 from 0.66 to 0.75. With Rasch analysis, the misfit was acceptable, except for the abdominal muscle strength item. The difficulty patterns were similar at admission and discharge, except for the abdominal muscle strength item. The responsiveness of the TIS was satisfactory and comparable with that of the Trunk Control Test (standardized response mean values, 0.94 and 1.06). Conclusions:Our newly developed TIS is reliable, valid, and responsive for use in stroke outcome research.

TRUNK MUSCLES IN PERSONS WITH HEMIPARETIC STROKE EVALUATED WITH COMPUTED TOMOGRAPHY

OBJECTIVES To analyse side difference in bilateral trunk muscles in patients with hemiparetic stroke, to relate it with impairment and disability variables and to evaluate longitudinal changes. METHODS In a sample of 83 inpatients with hemiparetic stroke undergoing rehabilitation, we measured the cross-sectional area of the paravertebral muscle and thigh muscles using computed tomography at admission and discharge. Classifying them by paravertebral muscle side difference (group I: contralateral > ipsilateral; II: contralateral = ipsilateral; III: contralateral < ipsilateral) we analysed group difference in the Stroke Impairment Assessment Set, the Functional Independence Measure and walk velocity. RESULTS In contrast to thigh muscles, the paravertebral muscle cross-sectional area was significantly greater on the side contralateral to the brain lesion. Discharge paravertebral muscle cross-sectional area increased significantly from admission values. The Stroke Impairment Assessment Set, Functional Independence Measure and walk velocity were significantly lower in group I. CONCLUSION The contralateral paravertebral muscle cross-sectional area was larger than the ipsilateral ones, and this was related to the degree of impairment and functional limitations.