STENOSIS: Long-term single versus dual antiplatelet therapy in patients with ischaemic stroke due to intracranial atherosclerotic disease - a randomised trial.

Rationale: Intracranial atherosclerotic disease (ICAD) is a pathological process that causes progressive stenosis and cerebral hypoperfusion, leading to stroke occurrence and recurrence around the world. The exact duration of dual antiplatelet therapy (DAPT) for ICAD is unclear in view of long-term risk of bleeding complications. Aim: The current study aims to study the efficacy and safety of long-term DAPT (up to 12 months) in patients with ICAD. Sample size: Using 80% power and an alpha error of 5 %, presuming a 10%-15% drop-out rate, a total of 2200 patients will be recruited for the study. Methodology: This is a prospective, randomised, double-blind, placebo controlled trial. Study outcomes: The primary outcomes include recurrent ischaemic stroke (IS) or transient ischaemic attack and any intracranial haemorrhage (ICH), major or minor systemic bleeding at the end of 12 months. Secondary outcomes include composite of any stroke, myocardial infarction or death at the end of 12 months. The safety outcomes include any ICH, major or minor bleeding as defined using GUSTO (Global Use of Streptokinase and tPA for occluded Coronary Arteries) classification at the end of 12 months and 1 month after completion of the drug treatment phase. Discussion: The study will provide level I evidence on the duration of DAPT among patients with IS due to ICAD of more than or equal to 50%.

Rivastigmine for Cognitive Impairment in Multiple Sclerosis: A Prospective Randomized Open Label study with Blinded End-Point Assessment.

Background and Objective: Nearly 40-65% patients with MS develop cognitive impairment during the disease. There is no treatment clearly effective in improving the cognitive deficits. To evaluate the efficacy and safety of Rivastigmine in cognitively impaired MS patients. Materials and Methods: This was a parallel group randomized open label study with blinded end-point assessment. The patient allocation to treatment and control arm was done by telephonic contact with an independent statistician who used a computer to generate a random sequence of allocation using permuted block randomization (varying block size of 4 and 6) in 1:1 ratio. The outcome assessor was blinded to this allocation. A total of 60 patients were in included in the study (30 in each arm). Primary outcome was improvement in memory functions (using logical memory subset of Wechsler Memory Scale III, India) assessed after 12 weeks. Secondary outcomes included fatigue, depression, and safety. Results: In modified intention to treat analysis (N = 22), treatment arm showed statistically significant improvement in memory function with mean difference of 7.56 [95% CI (0.67,14.46), p 0.032] as compared to control arm. There was no statistically significant difference in outcomes such as fatigue and depression. Vomiting was the most common side effect. No major adverse events were observed in either group. Conclusion: Rivastigmine is safe and effective in improving memory functions in cognitively impaired MS patients. However, our study has a small sample size and tested only a single domain. Larger studies with a validated single comprehensive neuropsychological test are needed.

Individualized closed-loop TMS synchronized with exoskeleton for modulation of cortical-excitability in patients with stroke: a proof-of-concept study.

Background: Repetitive TMS is used in stroke rehabilitation with predefined passive low and high-frequency stimulation. Brain State-Dependent Stimulation (BSDS)/Activity-Dependent Stimulation (ADS) using bio-signal has been observed to strengthen synaptic connections. Without the personalization of brain-stimulation protocols, we risk a one-size-fits-all approach. Methods: We attempted to close the ADS loop via intrinsic-proprioceptive (via exoskeleton-movement) and extrinsic-visual-feedback to the brain. We developed a patient-specific brain stimulation platform with a two-way feedback system, to synchronize single-pulse TMS with exoskeleton along with adaptive performance visual feedback, in real-time, for a focused neurorehabilitation strategy to voluntarily engage the patient in the brain stimulation process. Results: The novel TMS Synchronized Exoskeleton Feedback (TSEF) platform, controlled by the patient's residual Electromyogram, simultaneously triggered exoskeleton movement and single-pulse TMS, once in 10 s, implying 0.1 Hz frequency. The TSEF platform was tested for a demonstration on three patients (n = 3) with different spasticity on the Modified Ashworth Scale (MAS = 1, 1+, 2) for one session each. Three patients completed their session in their own timing; patients with (more) spasticity tend to take (more) inter-trial intervals. A proof-of-concept study on two groups-TSEF-group and a physiotherapy control-group was performed for 45 min/day for 20-sessions. Dose-matched Physiotherapy was given to control-group. Post 20 sessions, an increase in ipsilesional cortical-excitability was observed; Motor Evoked Potential increased by ~48.5 µV at a decreased Resting Motor Threshold by ~15.6%, with improvement in clinical scales relevant to the Fugl-Mayer Wrist/Hand joint (involved in training) by 2.6 units, an effect not found in control-group. This strategy could voluntarily engage the patient. Conclusion: A brain stimulation platform with a real-time two-way feedback system was developed to voluntarily engage the patients during the brain stimulation process and a proof-of-concept study on three patients indicates clinical gains with increased cortical excitability, an effect not observed in the control-group; and the encouraging results nudge for further investigations on a larger cohort.

Biosimilar Tenecteplase Versus Alteplase in Acute Ischemic Stroke: A Real World Study.

Background and Purpose: There is an unmet need for a more effective thrombolytic agent in acute ischemic stroke (AIS) management. Various studies and meta-analysis suggest tenecteplase (TNK) as non-inferior over alteplase (rTPA). The present single-center study compares biosimilar TNK and rTPA in a tertiary care setting. Methods: Data of patients who presented with AIS and underwent intravenous thrombolysis (IVT) were recruited retrospectively from January 2018 to July 2021. Primary efficacy outcome was a modified Rankin score (mRS) at 90 days dichotomized at < = 2. Qualitative and quantitative variables were assessed using Chi-square test and Student's t-test, respectively. Results: A total of 160 patients, 103 in the rTPA and 57 in TNK group, were analyzed. The baseline characteristics were well matched apart from hypertension. Large artery atherosclerosis was the most frequent subtype of stroke among the two groups. Good functional outcome was seen in 47.92% of patients TNK and 64.77% of patients in rTPA group (p = 0.069). No difference was seen in the rates of any ICH (p = 0.29) and mortality at 3 months (p = 0.32) among the two groups. Conclusion: This present study observed no difference in the efficacy and safety between biosimilar TNK and rTPA. Our findings are in concordance with published trials showing equivalence between the two molecules.

Collateral Circulation- Evolving from Time Window to Tissue Window.

Cerebral collateral circulation refers to the auxiliary vascular structures which compensate cerebral blood flow when it has been compromised due to stenosis or occlusion of the principal supplying arteries. They play a vital role in sustaining blood flow to the ischemic areas in acute, subacute or chronic phases of ischemic stroke or TIA. Good collateral circulation has shown protective effects towards a favorable functional outcome and a lower risk of recurrence of stroke. The benchmark mechanical thrombectomy trials utilized these collateral scoring methods to guide patient selection and prognosticate favorable outcome models. This shows a promising future of the collateral circulation for extending the time frame of the reperfusion therapies by optimally guiding patient selection and moving from a "time window" to a "tissue window."

Carotid Artery Stenting for a Nonagenarian Presenting as Stuttering Stroke.

Carotid artery stenting (CAS) is performed in patients with minor strokes and transient ischemic attacks (TIAs) to prevent further strokes. However, most operators do not intervene in older adults. We had a 92-year patient with recurrent minor strokes with two possible proximate causes - cardioembolism and significant symptomatic left carotid stenosis. This patient continued to have recurrent ischemic events in the left carotid territory despite optimum management of the cardioembolic source with dual antiplatelets and anticoagulation and was successfully treated with left CAS. The role of carotid revascularization in older patients with high-grade symptomatic carotid stenosis and cardiac comorbidities is discussed.

Study Protocol: IMPETUS: Implementing a Uniform Stroke Care Pathway in Medical Colleges of India: IMPETUS Stroke.

Introduction: In India, a national program for stroke (national programme for the control of cardiovascular diseases, diabetes, cancer, and stroke) and stroke management guidelines exist. Its successful implementation would need an organized system of stroke care in practice. However, many challenges exist including lack of awareness, prehospital notification systems, stroke ready hospitals, infrastructural weaknesses, and rehabilitation. We present here a protocol to investigate the feasibility and fidelity of implementing a uniform stroke care pathway in medical colleges of India. Methods and Analysis: This is a multicentric, prospective, multiphase, mixed-method, quasi-experimental implementation study intended to examine the changes in a select set of stroke care-related indicators over time within the sites exposed to the same implementation strategy. We shall conduct process evaluation of the implementation process as well as evaluate the effect of the implementation strategy using the interrupted time series design. During implementation phase, education and training about standard stroke care pathway will be provided to all stakeholders of implementing sites. Patient-level outcomes in the form of modified Rankin Scale score will be collected for all consecutive patients throughout the study. Process evaluation outcomes will be collected and reported in the form of various stroke care indicators. We will report level and trend changes in various indicators during the three study phases. Discussion: Acute stroke requires timely detection, management, and secondary prevention. Implementation of the uniform stroke care pathway is a unique opportunity to promote the requirements of homogenous stroke care in medical colleges of India.

Impact of the COVID-19 Pandemic on the Frequency, Clinical Spectrum and Outcomes of Pediatric Guillain-Barré Syndrome in India: A Multicentric Ambispective Cohort Study.

Objective: To study impact of COVID-19 pandemic on frequency, clinical/electrophysiological profile and treatment outcomes in pediatric Guillain-Barré syndrome (GBS). Background: GBS is the most frequent cause of pediatric acute flaccid paralysis. The effect of the COVID-19 pandemic on pediatric GBS is unclear in the literature. Methods: We conducted an ambispective, multicentric, cohort study involving 12 of 27 centres in GBS Consortium, during two periods: pre-COVID-19 (March-August 2019) and during COVID-19 (March-August 2020). Children ≤12 years who satisfied National Institute of Neurological Diseases and Stroke criteria for GBS/variants were enrolled. Details pertaining to clinical/laboratory parameters, treatment and outcomes (modified Rankin Scale (mRS) at discharge, GBS Disability score at discharge and 3 months) were analysed. Results: We enrolled 33 children in 2019 and 10 in 2020. Children in 2020 were older (median 10.4 [interquartile range 6.75-11.25] years versus 5 (2.5-8.4) years; P = 0.022) and had more sensory symptoms (50% versus 18.2%; P = 0.043). The 2020 group had relatively favourable mRS at discharge (median 1 (1-3.5) versus 3 (2-4); P = 0.042) and GBS disability score at 3 months (median 0 (0-0.75) versus 2 (0-3); P = 0.009) compared to 2019. Multivariate analysis revealed bowel involvement (P = 0.000) and ventilatory support (P = 0.001) as independent predictors of disability. No child in 2020 had preceding/concurrent SARS-CoV2 infection. Conclusions: The COVID-19 pandemic led to a marked decline in pediatric GBS presenting to hospitals. Antecedent illnesses, clinical and electrophysiological profile of GBS remained largely unchanged from the pre-pandemic era.

Impact of COVID-19 on Guillain-Barre Syndrome in India: A Multicenter Ambispective Cohort Study.

Introduction/Aims: Studies conducted during the coronavirus disease 2019 (COVID-19) pandemic have reported varied data regarding the incidence of Guillain-Barre syndrome (GBS). The present study investigated demographic and clinical features, management, and outcomes of patients with GBS during a specified period of the COVID-19 pandemic, and compared these features to those of GBS in the previous year. Methods: A multicenter, ambispective cohort study including 26 centers across India was conducted. Data from a pre-COVID-19 period (March 1 to August 31, 2019) were collected retrospectively and collected ambispectively for a specified COVID-19 period (March 1 to August 31, 2020). The study was registered with the Clinical Trial Registry India (CTRI/2020/11/029143). Results: Data from 555 patients were included for analysis: pre-COVID-19 (n = 334) and COVID-19 (n = 221). Males were more commonly affected during both periods (male:female, 2:1). Gastroenteritis was the most frequent antecedent event in 2019 (17.4%), whereas fever was the most common event in 2020 (10.7%). Paraparesis (21.3% versus [vs.] 9.3%, P = 0.001) and sensory involvement (51.1% vs. 41.3%; P = 0.023) were more common during COVID-19 in 2020, whereas back pain (26.3% vs. 18.4%; P = 0.032) and bowel symptoms (20.7% vs. 13.7%; P = 0.024) were more frequent in the pre-COVID period. There was no difference in clinical outcomes between the two groups in terms of GBS disability score at discharge and 3 months after discharge. Independent predictors of disability in the pre-COVID period included areflexia/hyporeflexia, the requirementfor intubation, and time to bulbar weakness; in the COVID-19 period, independent predictors included time from onset to admission, intubation, and intubation requirement. The mortality rate was 2.3% during the entire study period (13/555 cases). Discussion: Results of this study revealed an overall reduction in the frequency of GBS during the pandemic. The lockdown likely reduced the risk for antecedent infections due to social distancing and improved hygiene, which may have resulted in the reduction of the frequency of GBS.

Predictors of Seizures and Associated Functional Outcome in a Cerebral Venous Thrombosis Cohort: An Ambispective Cohort Study.

Background and Purpose: We aimed to explore the characteristics, clinical features, predictors of seizure, and associated clinical outcomes in patients with cerebral venous thrombosis (CVT). Methods: We enrolled patients with CVT from January 2014 to July 2020. Prospectively patients were recruited from December 2018. We analyzed predictors of seizures and associated good functional outcomes (modified Rankin Scale, mRS: 0-2) using multivariable logistic regression. Results: We enrolled 153 patients with CVT in which 77 (50%) had presented with a seizure. The median age was 31 years (IQR 16-46), and the majority were men (73.2%). Focal to bilateral tonic-clonic was the most common seizure type (27%), followed by generalized seizures (22%). None of the patients had status epilepticus. Antiseizure medications (ASM) were used in 71% of patients at diagnosis, 42% having received them prophylactically. Supratentorial parenchymal involvement was seen in 72% of seizure patients compared to 38% in those without, and superior sagittal sinus was most commonly involved. Percentage of patients who achieved good clinical outcome (mRS 0-2) at 3 months did not vary significantly between both groups. The only predictor for seizures with CVT was the presence of a parenchymal lesion (OR-3.75, 95% CI 1.79-7.85), whereas seizure occurrence (OR- 12.55, 95% CI- 1.53-102.59) was associated with statistically significant risk for recurrent seizures, by multiple logistic regression analysis. Seizure occurrence was not associated with adverse functional outcomes. Conclusion: Seizures at presentation occurred in 50% of patients with CVT which was associated with a parenchymal lesion in the brain. There was no association between seizure at presentation and clinical outcome.

Critical Appraisal of a Machine Learning Paper: A Guide for the Neurologist.

Machine learning (ML), a form of artificial intelligence (AI), is being increasingly employed in neurology. Reported performance metrics often match or exceed the efficiency of average clinicians. The neurologist is easily baffled by the underlying concepts and terminologies associated with ML studies. The superlative performance metrics of ML algorithms often hide the opaque nature of its inner workings. Questions regarding ML model's interpretability and reproducibility of its results in real-world scenarios, need emphasis. Given an abundance of time and information, the expert clinician should be able to deliver comparable predictions to ML models, a useful benchmark while evaluating its performance. Predictive performance metrics of ML models should not be confused with causal inference between its input and output. ML and clinical gestalt should compete in a randomized controlled trial before they can complement each other for screening, triaging, providing second opinions and modifying treatment.