The Effect of Passive Movement for Paretic Ankle-Foot and Brain Activity in Post-Stroke Patients.

BACKGROUND: This study aims at investigating the short-term efficacy of the continuous passive motion (CPM) device developed for the therapy of ankle-foot paresis and to investigate by fMRI the blood oxygen level-dependent responses (BOLD) during ankle passive movement (PM). METHODS: Sixty-four stroke patients were investigated. Patients were assigned into 2 groups: 49 patients received both 15 min manual and 30 min device therapy (M + D), while the other group (n = 15) received only 15 min manual therapy (M). A third group of stroke patients (n = 12) was investigated by fMRI before and immediately after 30 min CPM device therapy. There was no direct relation between the fMRI group and the other 2 groups. All subjects were assessed using the Modified Ashworth Scale (MAS) and a goniometer. RESULTS: Mean MAS decreased, the ankle's mean plantar flexion and dorsiflexion passive range of motion (PROM) increased and the equinovalgus improved significantly in the M + D group. In the fMRI group, the PM of the paretic ankle increased BOLD responses; this was observed in the contralateral pre- and postcentral gyrus, superior temporal gyrus, central opercular cortex, and in the ipsilateral postcentral gyrus, frontal operculum cortex and cerebellum. CONCLUSION: Manual therapy with CPM device therapy improved the ankle PROM, equinovalgus and severity of spasticity. The ankle PM increased ipsi- and contralateral cortical activation.

[Experiences with a self developed accelerometer]. / Saját fejlesztésu mozgásérzékelovel szerzett tapasztalataink.

OBJECTIVE: In neurology the objective evaluation of improvement of paresis on every-day practice. The aim of this study was to develop and test a small 3-d acceleration measuring device and validate its usefulness. PATIENTS AND METHODS: We collected data from 17 mild and medium severity hemiparetic, bedridden acute ischaemic and hemorrhagic stroke patients and compared with data of 22 control subjects. The devices were attached to the paretic and non-paretic extremities and any movements (m/s2) and movement-durations were registered (24h). The data of movement-monitors were compared also with the changes of National Institute of Health Stroke Scale and European Stroke Scale. The electromyograph-sensor of polysomnograph was used for validation. RESULTS: Mild differences could be found in the use of dominant and non-dominant upper extremities of control persons. The control persons used their upper extremities more frequently than the stroke patients. Our data showed significant correlation with National Institute of Health Stroke Scale. Higher values on the scores were accompanied with less intensive use of extremities. We found a correlation between the consiousness level of patients and their activity of upper extremities. If the patients had severe consiousness disturbances they used significantly less their upper extremities. CONCLUSION: Our device sensitively detected the movement-differences between paretic and non-paretic extremities and can be used for quantitative evaluation of patient's neurological and consciousness status.

[Anticoagulant therapy in practice]. / Antikoagulálás a gyakorlatban.

UNLABELLED: Atrial fibrillation is a risk factor for ischemic stroke. To prevent stroke oral anticoagulants can be administered. Old and new types of anticoagulants are available. Nowadays, old type, acenocumarol based anticoagulants are used preferentially in Hungary. AIM: The advantages and the disadvantages of anticoagulants are well known, but anticoagulants are underused in many cases. METHOD: The authors retrospectively examined how frequent atrial fibrillation was and whether the usage of anticoagulants in practice was in accordance with current guidelines among acute stroke cases admitted to the Department of Neurology, Medical and Health Science Centre of Debrecen University in 2009. RESULTS: Of the 461 acute stroke cases, 96 patients had known and 22 patients had newly discovered atrial fibrillation. Half of the patients did not receive proper anticoagulation. Only 8.4% of them had their INR levels within the therapeutic range. CONCLUSIONS: The findings are similar to those reported in other studies. Many factors may contribute to the high proportion of improper use of anticoagulants, and further investigations are needed to determine these factors. In any case, elimination of these factors leading to a failure of anticoagulation may decrease the incidence of stroke.

Effective connectivity differences in motor network during passive movement of paretic and non-paretic ankles in subacute stroke patients.

BACKGROUND: A better understanding of the neural changes associated with paresis in stroke patients could have important implications for therapeutic approaches. Dynamic Causal Modeling (DCM) for functional magnetic resonance imaging (fMRI) is commonly used for analyzing effective connectivity patterns of brain networks due to its significant property of modeling neural states behind fMRI signals. We applied this technique to analyze the differences between motor networks (MNW) activated by continuous passive movement (CPM) of paretic and non-paretic ankles in subacute stroke patients. This study aimed to identify CPM induced connectivity characteristics of the primary sensory area (S1) and the differences in extrinsic directed connections of the MNW and to explain the hemodynamic differences of brain regions of MNW. METHODS: For the network analysis, we used ten stroke patients' task fMRI data collected under CPMs of both ankles. Regions for the MNW, the primary motor cortex (M1), the premotor cortex (PM), the supplementary motor area (SMA) and the S1 were defined in a data-driven way, by independent component analysis. For the network analysis of both CPMs, we compared twelve models organized into two model-families, depending on the S1 connections and input stimulus modeling. Using DCM, we evaluated the extrinsic connectivity strengths and hemodynamic parameters of both stimulations of all patients. RESULTS: After a statistical comparison of the extrinsic connections and their modulations of the "best model", we concluded that three contralateral self-inhibitions (cM1, cS1 and cSMA), one contralateral inter-regional connection (cSMA→cM1), and one interhemispheric connection (cM1→iM1) were significantly different. Our research shows that hemodynamic parameters can be estimated with the Balloon model using DCM but the parameters do not change with stroke. CONCLUSIONS: Our results confirm that the DCM-based connectivity analyses combined with Bayesian model selection may be a useful technique for quantifying the alteration or differences in the characteristics of the motor network in subacute stage stroke patients and in determining the degree of MNW changes.

Population-Level Correction of Systematic Motion Artifacts in fMRI in Patients with Ischemic Stroke.

BACKGROUND: The aim of this study was to reveal potential sources of systematic motion artifacts in stroke functional magnetic resonance imaging (fMRI) focusing on those causing stimulus-correlated motion on the individual-level and separate the motion effect on the fMRI signal changing from the activation-induced alteration at population level. METHODS: Eleven ischemic stroke patients were examined by fMRI. The fMRI paradigm was based on passive ankle movement on both the healthy and the paretic leg's side. Three individual-level motion correction strategies were compared and we introduced five measures to characterize each subjects' in-scanner relative head movement. After analyzing the correlation of motion parameters and the subjects' physiological scale scores, we selected a parameter to model the motion-related artifacts in the second-level analysis. RESULTS: At first (individual) level analysis, the noise-component correction-based CompCor method provided the highest -log10(p) value of cluster-level occurrence probability at 12.4/13.6 for healthy and paretic side stimulus, respectively, with a maximal z-value of 15/16.3. Including the motion parameter at second (group) level resulted in lower cluster occurrence values at 10.9/5.55 while retaining the maximal z-value. CONCLUSIONS: We proposed a postprocessing pipeline for ischemic stroke fMRI data that combine the CompCor correction at first level with the modeling of motion effect at second-level analysis by a parameter obtained from fMRI data. Our solution is applicable for any fMRI-based stroke rehabilitation study since it does not require any MRI-compatible motion capture system and is based on commonly used methods.