Scholars@Duke
Pratik Yashvant Chhatbar

Pratik Yashvant Chhatbar

Adjunct Assistant Professor in the Department of Neurology
Neurology, Stroke and Vascular Neurology
pratik.chhatbar@duke.edu
40 Duke Medicine Circle, Duke South, Suite 3052, DUMC Box 3824, Durham, NC 27710
40 Duke Medicine Circle, Duke Clinic Suite 3052, Durham, NC 27710

Selected Publications

Revisiting Transcranial Light Stimulation as a Stroke Therapeutic-Hurdles and Opportunities.

Journal Article Transl Stroke Res · December 2023 Near-infrared laser therapy, a special form of transcranial light therapy, has been tested as an acute stroke therapy in three large clinical trials. While the NEST trials failed to show the efficacy of light therapy in human stroke patients, there are man ... Full text Link to item Cite

Numerical and experimental evaluation of low-intensity transcranial focused ultrasound wave propagation using human skulls for brain neuromodulation.

Journal Article Med Phys · January 2023 BACKGROUND: Low-intensity transcranial focused ultrasound (tFUS) has gained considerable attention as a promising noninvasive neuromodulatory technique for human brains. However, the complex morphology of the skull hinders scholars from precisely predictin ... Full text Link to item Cite

Microdermabrasion facilitates direct current stimulation by lowering skin resistance.

Journal Article Skin Health Dis · September 2022 BACKGROUND: Transcranial direct current stimulation (tDCS) is reported to induce irritating skin sensations and occasional skin injuries, which limits the applied tDCS dose. Additionally, tDCS hardware safety profile prevents high current delivery when ski ... Full text Link to item Cite

Similarities Between Somatosensory Cortical Responses Induced via Natural Touch and Microstimulation in the Ventral Posterior Lateral Thalamus in Macaques.

Journal Article Front Neurosci · 2022 Lost sensations, such as touch, could be restored by microstimulation (MiSt) along the sensory neural substrate. Such neuroprosthetic sensory information can be used as feedback from an invasive brain-machine interface (BMI) to control a robotic arm/hand, ... Full text Link to item Cite

In vivo Measurements of Electric Fields During Cranial Electrical Stimulation in the Human Brain.

Journal Article Front Hum Neurosci · 2022 Cranial electrical stimulation (CES) has been applied at various current levels in both adults and children with neurological conditions with seemingly promising but somewhat inconsistent results. Stimulation-induced spatial electric fields (EFs) within a ... Full text Link to item Cite

Intracranial Electric Field Recording During Multichannel Transcranial Electrical Stimulation

Journal Article · December 21, 2021 AbstractBackgroundMultichannel transcranial electrical stimulation (tES) modeling and optimization have been widely studied in recent years. Its theoretical bases include quasi-static assu ... Full text Cite

Structural and Functional Imaging of the Retina in Central Retinal Artery Occlusion - Current Approaches and Future Directions.

Journal Article J Stroke Cerebrovasc Dis · July 2021 Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke which affects the retina. Intravenous thrombolysis is emerging as a compelling therapeutic approach. However, it is not known which patients may benefit from this therapy because th ... Full text Link to item Cite

Abstract P592: Admission Hyperglycemia is Associated With Subsequent Ischemic Stroke After Transient Ischemic Attack or Minor Stroke: A Secondary Analysis of the POINT Trial

Conference Stroke · March 2021 Introduction: Hyperglycemia is associated with increased lesion volume and worse functional outcome after acute ischemic stroke, however, it is not known whether it is associated with further cerebrov ... Full text Cite

Abstract MP46: Internal Carotid Artery Web and Acute Ischemic Stroke - A Systematic Review and Meta-Analysis

Conference Stroke · March 2021 Introduction: The carotid web is a compelling potential mechanism of embolic ischemic stroke. In this study, we perform a systematic review and meta-analysis to determine the prevalence of ipsilesiona ... Full text Cite

Effect of Low Intensity Transcranial Ultrasound Stimulation on Neuromodulation in Animals and Humans: An Updated Systematic Review.

Journal Article Front Neurosci · 2021 Background: Although low-intensity transcranial ultrasound stimulation (LI-TUS) has received more recognition for its neuromodulation potential, there remains a crucial knowledge gap regarding the neuromodulatory effects of LI-TUS and its potential for tra ... Full text Link to item Cite

Direct Communication Between Brains: A Systematic PRISMA Review of Brain-To-Brain Interface.

Journal Article Front Neurorobot · 2021 This paper aims to review the current state of brain-to-brain interface (B2BI) technology and its potential. B2BIs function via a brain-computer interface (BCI) to read a sender's brain activity and a computer-brain interface (CBI) to write a pattern to a ... Full text Open Access Link to item Cite

Biosafety of low-intensity pulsed transcranial focused ultrasound brain stimulation - A human skull study

Conference Proceedings of SPIE - The International Society for Optical Engineering · January 1, 2021 Among a variety of existing modalities for noninvasive brain stimulation (NIBS), low-intensity pulsed transcranial focused ultrasound (tFUS) is a promising technique to precisely stimulate deep brain structures due to its high spatial specificity and super ... Full text Cite

National Institutes of Health StrokeNet Training Core.

Journal Article Stroke · January 2020 Background and Purpose- The National Institutes of Health (NIH) StrokeNet provides a nationwide infrastructure to advance stroke research. Capitalizing on this unique opportunity, the NIH StrokeNet Training Core (NSTC) was established with the overarching ... Full text Link to item Cite

Mesenchymal Stem Cell Therapy in Stroke: A Systematic Review of Literature in Pre-Clinical and Clinical Research.

Journal Article Cell Transplant · December 2018 Exogenous stem cell therapy (SCT) has been recognized recently as a promising neuroregenerative strategy to augment recovery in stroke survivors. Mesenchymal stem cells (MSCs) are the primary source of stem cells used in the majority of both pre-clinical a ... Full text Link to item Cite

Transcranial Direct Current Stimulation for Poststroke Motor Recovery: Challenges and Opportunities.

Journal Article PM R · September 2018 There has been a renewed research interest in transcranial direct current stimulation (tDCS) as an adjunctive tool for poststroke motor recovery as it has a neuro-modulatory effect on the human cortex. However, there are barriers towards its successful app ... Full text Link to item Cite

Evidence of transcranial direct current stimulation-generated electric fields at subthalamic level in human brain in vivo.

Journal Article Brain Stimul · 2018 BACKGROUND: Transcranial direct current stimulation (tDCS) is a promising brain modulation technique for several disease conditions. With this technique, some portion of the current penetrates through the scalp to the cortex and modulates cortical excitabi ... Full text Open Access Link to item Cite

Mobile health as a viable strategy to enhance stroke risk factor control: A systematic review and meta-analysis.

Journal Article Journal of the neurological sciences · July 2017 BackgroundWith the rapid growth worldwide in cell-phone use, Internet connectivity, and digital health technology, mobile health (mHealth) technology may offer a promising approach to bridge evidence-treatment gaps in stroke prevention. We aimed t ... Full text Cite

Safety and tolerability of transcranial direct current stimulation to stroke patients - A phase I current escalation study.

Journal Article Brain Stimul · 2017 BACKGROUND AND OBJECTIVE: A prior meta-analysis revealed that higher doses of transcranial direct current stimulation (tDCS) have a better post-stroke upper-extremity motor recovery. While this finding suggests that currents greater than the typically used ... Full text Link to item Cite

Neural correlates of single-vessel haemodynamic responses in vivo.

Journal Article Nature · June 16, 2016 Neural activation increases blood flow locally. This vascular signal is used by functional imaging techniques to infer the location and strength of neural activity. However, the precise spatial scale over which neural and vascular signals are correlated is ... Full text Link to item Cite

Transcranial Direct Current Stimulation Post-Stroke Upper Extremity Motor Recovery Studies Exhibit a Dose-Response Relationship.

Journal Article Brain Stimul · 2016 BACKGROUND AND PURPOSE: Transcranial direct current stimulation (tDCS) has shown mixed results in post-stroke motor recovery, possibly because of tDCS dose differences. The purpose of this meta-analysis was to explore whether the outcome has a dose-respons ... Full text Link to item Cite

Corticospinal tract lesion load: An imaging biomarker for stroke motor outcomes.

Journal Article Ann Neurol · December 2015 OBJECTIVE: The aim of this work was to investigate whether an imaging measure of corticospinal tract (CST) injury in the acute phase can predict motor outcome at 3 months in comparison to clinical assessment of initial motor impairment. METHODS: A two-site ... Full text Link to item Cite

Ethical considerations of neuroprostheses

Chapter · March 4, 2015 Neuroprosthetics has enjoyed increasing interest among researchers, health care professionals, the media, and the general public over the past few decades. New developments in neuroprostheses are the result of increased collaboration among those working in ... Full text Cite

Improved blood velocity measurements with a hybrid image filtering and iterative Radon transform algorithm

Journal Article Frontiers in Neuroscience · January 1, 2013 Neural activity leads to hemodynamic changes which can be detected by functional magnetic resonance imaging (fMRI). The determination of blood flow changes in individual vessels is an important aspect of understanding these hemodynamic signals. Blood flow ... Full text Cite

Towards a naturalistic brain-machine interface: hybrid torque and position control allows generalization to novel dynamics.

Journal Article PLoS One · 2013 Realization of reaching and grasping movements by a paralytic person or an amputee would greatly facilitate her/his activities of daily living. Towards this goal, control of a computer cursor or robotic arm using neural signals has been demonstrated in rod ... Full text Link to item Cite

Neuroprostheses: Implications of the current and future state of the science and technology

Chapter · January 1, 2012 Neuroprosthetics is a science of neural prostheses. Neural prostheses can be dešned as devices that are yoked or implanted in the peripheral or central nervous system to restore or improve neural function (Segen 2005). Neuroprosthetics thus represents that ... Full text Cite

An artery-specific fluorescent dye for studying neurovascular coupling.

Journal Article Nature methods · January 2012 We demonstrate that Alexa Fluor 633 hydrazide (Alexa Fluor 633) selectively labels neocortical arteries and arterioles by binding to elastin fibers. We measured sensory stimulus-evoked arteriole dilation dynamics in mouse, rat and cat visual cortex using A ... Full text Cite

Stochastic kernel temporal difference for reinforcement learning

Conference IEEE International Workshop on Machine Learning for Signal Processing · December 5, 2011 This paper introduces a kernel adaptive filter using the stochastic gradient on temporal differences, kernel TD(λ), to estimate the state-action value function Q in reinforcement learning. Kernel methods are powerful for solving nonlinear problems, but the ... Full text Cite

Sparse coding of movement-related neural activity

Conference 2011 IEEE Signal Processing in Medicine and Biology Symposium, SPMB 2011 · December 1, 2011 Modern systems neuroscience benefits from the ability to record from and digitize a large amount of functional data from hundreds or even thousands of neurons. Understanding, transmitting, storing, and parsing information of such volume and complexity call ... Full text Cite

Control of a center-out reaching task using a reinforcement learning Brain-Machine Interface

Conference 2011 5th International IEEE/EMBS Conference on Neural Engineering, NER 2011 · July 20, 2011 In this work, we develop an experimental primate test bed for a center-out reaching task to test the performance of reinforcement learning based decoders for Brain-Machine Interfaces. Neural recordings obtained from the primary motor cortex were used to ad ... Full text Cite

Reinforcement learning via kernel temporal difference.

Conference Annu Int Conf IEEE Eng Med Biol Soc · 2011 This paper introduces a kernel adaptive filter implemented with stochastic gradient on temporal differences, kernel Temporal Difference (TD)(λ), to estimate the state-action value function in reinforcement learning. The case λ=0 will be studied in this pap ... Full text Link to item Cite

A bio-friendly and economical technique for chronic implantation of multiple microelectrode arrays.

Journal Article J Neurosci Methods · May 15, 2010 Many neurophysiological experiments on rodents and non-human primates involve the implantation of more than one multi-electrode array to record from many regions of the brain. So called 'floating' microelectrode arrays are implanted in cortical regions of ... Full text Link to item Cite

Comparison of force and power generation patterns and their predictions under different external dynamic environments.

Conference Annu Int Conf IEEE Eng Med Biol Soc · 2010 Use of neural activity to predict kinematic variables such as position, velocity and direction etc of movements has been implemented in real-time control of robotic systems and computer cursors. In everyday life, however, we generate variable amounts of fo ... Full text Link to item Cite

The future of implantable neuroprosthetic devices: ethical considerations.

Journal Article J Long Term Eff Med Implants · 2009 From well-established results with cochlear implants to the advent of implantable microelectrode arrays, implantable neuroprosthetic devices have gained increasing attention from health care professionals, scientists, engineers, and the general population. ... Full text Link to item Cite