Lateralized readiness potentials can identify hemisphere of recovery in stroke patients.

BACKGROUND: Event related cortical potentials related to motor action are referred to as movement related cortical potentials. The late component of which is the readiness potential (RP) and its polarity is more negative in the hemisphere responsible for planning of motor action. This lateralized nature of RP during unilateral hand movement is studied as lateralized readiness potential (LRP) by calculating the contralateral-minus-ipsilateral difference wave for each hand. OBJECTIVE: The aim was to identify the hemisphere contributing to motor recovery in acute and chronic stroke patients through recording LRPs. METHODS: Twenty-nine cases with cerebrovascular stroke (15 acute and 14 chronic) were included in the study. EEG was recorded in response to self-cued button presses by the paretic side to obtain the averaged LRP amplitude. The hemisphere with greater negativity was considered the side of recovery. Functional recovery was assessed by Fugl Meyer test. RESULTS: In acute cases, recovery was more related to LRP activity in the contralesional hemisphere (73%), whereas lateralization was equal in chronic cases; 50% in either group. LRP amplitude was higher in the contralesional hemisphere (p = 0.02). Functional recovery assessed by the Fugl Meyer test (FM) was similar whether recovery was ipsi- or contralesional. CONCLUSIONS: Early after stroke, motor recovery is more likely to involve compensatory activity in the contralesional hemisphere, while in the chronic phase, the ipsilesional hemisphere may recover its function and become more active. Further research is needed to verify if the technique mentioned in our study could be used to guide customized NIBS protocols tailoring the optimal site and parameters for each patient.

Peripheral magnetic theta burst stimulation to muscles can effectively reduce spasticity: a randomized controlled trial.

BACKGROUND: Spasticity is a common complication of many neurological diseases and despite contributing much disability; the available therapeutic options are limited. Peripheral magnetic stimulation is one promising option. In this study, we investigated whether peripheral intermittent theta burst stimulation (piTBS) will reduce spasticity when applied directly on spastic muscles. METHODS: In this sham-controlled study, eight successive sessions of piTBS were applied directly to spastic muscles with supra threshold intensity. Assessment was done by modified Ashworth scale (mAS) and estimated Botulinum toxin dose (eBTD) at baseline and after the 8th session in both active and sham groups. RESULTS: A total of 120 spastic muscles of 36 patients were included in the analysis. Significant reduction of mAS and eBTD was found in the active compared to sham group (p < 0.001). The difference in mAS was also significant when tested in upper limb and lower limb subgroups. The degree of reduction in mAS was positively correlated with the baseline scores in the active group. CONCLUSION: piTBS could be a promising method to reduce spasticity and eBTD. It consumes less time than standard high frequency protocols without compromising treatment efficacy. TRIAL REGISTRATION: Clinical trial registry number: PACTR202009622405087. Retrospectively Registered 14th September, 2020.

Design of a Data Glove for Assessment of Hand Performance Using Supervised Machine Learning.

The large number of poststroke recovery patients poses a burden on rehabilitation centers, hospitals, and physiotherapists. The advent of rehabilitation robotics and automated assessment systems can ease this burden by assisting in the rehabilitation of patients with a high level of recovery. This assistance will enable medical professionals to either better provide for patients with severe injuries or treat more patients. It also translates into financial assistance as well in the long run. This paper demonstrated an automated assessment system for in-home rehabilitation utilizing a data glove, a mobile application, and machine learning algorithms. The system can be used by poststroke patients with a high level of recovery to assess their performance. Furthermore, this assessment can be sent to a medical professional for supervision. Additionally, a comparison between two machine learning classifiers was performed on their assessment of physical exercises. The proposed system has an accuracy of 85% (±5.1%) with careful feature and classifier selection.

Borderzone Infarction and Small Vessel Disease in a Sample of Egyptian Stroke Patients: Differences and Similarities.

BACKGROUND: The anatomical location of white matter hyperintense lesions in small vessel disease are apparently similar to those of borderzone infarction. The objective of this study is to find clinical and radiological points of differentiation between the two vascular disorders in a sample of Egyptian patients which might have an impact on primary and secondary prevention. METHODS: Ischemic stroke patients with white matter lesions were categorized into two groups: small vessel disease and borderzone infarctions. NIHSS was done on admission. Risk factor profile was reported, and investigations done including: HbA1C, lipid profile, CRP, ECG, echocardiography, carotid duplex, brain MRI, MRA and MR perfusion study. RESULTS: 46 patients completed the study, 29 with SVD and 17 with BZI. Smoking, hypertension and recurrent stroke were more common in borderzone infarctions, but only diabetes was significantly higher (p = 0.047). Limb shaking was more observed in borderzone infarctions (p = 0.049). Radiologically: lacunar pattern was observed more in small vessel disease, while rosary pattern was more in borderzone infarctions (p = 0.04). FLAIR symmetrical lesions and microbleeds were more significant in small vessel disease (p = <0.001; 0.048, respectively). Perfusion study time to peak denoted evidence of significant hypoperfusion in all regions of interest in borderzone infarctions. CONCLUSION: Limb shaking, retinal claudication or syncope, with MRI showing rosary pattern of white matter hyperintensity, few microbleeds and markedly impaired perfusion favor the diagnosis of borderzone infarctions. On the other hand, presence of lacunae, FLAIR showing symmetrical WMH and microbleeds with minimal or no perfusion deficit suggests the diagnosis of small vessel disease.

Navigated perilesional transcranial magnetic stimulation can improve post-stroke visual field defect: A double-blind sham-controlled study.

BACKGROUND: Visual field defects (VFD) usually do not show improvement beyond 12 weeks from their onset. It has been shown that repetitive presentation of a stimulus to areas of residual vision in cases of visual field defect can improve vision. The counterpart of these areas in the brain are the partially damaged brain regions at the perilesional areas where plasticity can be enhanced. OBJECTIVE: We aimed to study the effect of navigated repetitive transcranial magnetic stimulation (rTMS) applied to perilesional areas on the recovery of patients with cortical VFD. METHODS: Thirty-two patients with cortical VFD secondary to stroke of more than 3 months duration received 16 sessions of either active or sham high frequency navigated perilesional rTMS. Automated perimetry and visual functioning questionnaire (VFQ-25) were performed at baseline and after completion of the sessions. RESULTS: The active group showed significant improvement after intervention, compared to the sham group, in both mean deviation (MD), visual field index (VFI) and in the VFQ-25 scores. CONCLUSIONS: Navigated rTMS is a new treatment option for post-stroke VFD as it can selectively stimulate areas of residual vision around the infarcted tissue, improving the threshold of visual stimulus detection which could be used alone or in combination with existing therapies.