Abstract Lumbar diskitis/osteomyelitis (LDO) can cause destruction of the anterior and middle spinal column leading to loss of structural integrity further compounded by iatrogenic violation of the posterior tension band during initial... more
Abstract Lumbar diskitis/osteomyelitis (LDO) can cause destruction of the anterior and middle spinal column leading to loss of structural integrity further compounded by iatrogenic violation of the posterior tension band during initial decompressive surgeries. Progressive deformity and/or medically refractory infection may necessitate aggressive debridement and reconstructive arthrodesis. Anterior debridement and reconstruction with posterior stabilization is an effective treatment option; however, existing open surgical techniques have limited efficacy for correction of the focal deformity, which can expose the patient to long term sagittal imbalance, pain, and disability. The aim of this chapter is to briefly review the epidemiology, pathophysiology, clinical presentation, and the role of medical versus surgical management in LDO. The role of the lateral retroperitoneal approach to the lumbar spine is then discussed and illustrated with two clinical cases.
Research Interests:
Research Interests:
BACKGROUNDSynovial sarcoma of the nerve is a rare entity with several cases and case series reported in the literature. Despite an improved understanding of the biology, the clinical course is difficult to predict.OBJECTIVETo compile a... more
BACKGROUNDSynovial sarcoma of the nerve is a rare entity with several cases and case series reported in the literature. Despite an improved understanding of the biology, the clinical course is difficult to predict.OBJECTIVETo compile a series of patients with synovial sarcoma of the peripheral nerve (SSPN) and assess clinical and pathological factors and their contribution to survival and recurrence.METHODSCases from 2 institutions collected in patients undergoing surgical intervention for SSPN. Systematic review including PubMed and Scopus databases were searched for related articles published from 1970 to December 2018. Eligibility criteria: (1) case reports or case series reporting on SSPN, (2) clinical course and/or pathological features of the tumor reported, and (3) articles published in English.RESULTSFrom patients treated at our institutions (13) the average follow-up period was 3.2 yr. Tumor recurrence was seen in 4 cases and death in 3. Systematic review of the literature yielded 44 additional cases with an average follow-up period of 3.6 yr. From pooled data, there were 10 recurrences and 7 deaths (20% and 14%, respectively). Adjuvant treatment used in 62.5% of cases. Immunohistochemical markers used in diagnosis varied widely; the most common are the following: Epithelial membrane antigen (EMA), cytokeratin, vimentin, cluster of differentiation (CD34), and transducin-like enhancer of split 1 (TLE1). Statistical analysis illustrated tumor size and use of chemotherapy to be negative predictors of survival. No other factors, clinically or from pathologist review, were correlated with recurrence or survival.CONCLUSIONBy combining cases from our institution with historical data and performing statistical analysis we show correlation between tumor size and death.
Research Interests:
BACKGROUND Laser interstitial thermal therapy (LITT) presents an important new minimally invasive tool in the management of drug-resistant mesial temporal epilepsy (MTE). However, because of its relative novelty, not much is known about... more
BACKGROUND Laser interstitial thermal therapy (LITT) presents an important new minimally invasive tool in the management of drug-resistant mesial temporal epilepsy (MTE). However, because of its relative novelty, not much is known about long-term seizure freedom rates. The objective of this study was to evaluate the postsurgical seizure outcome following LITT after a minimum follow-up period of 2 years. METHODS Medical records of all patients who underwent LITT for MTE from 2013 to 2018 at our comprehensive epilepsy center under a single surgeon were retrospectively reviewed. Data related to demographics, presurgical evaluations, and seizure outcome were compared between seizure-free (SF) and non-seizure-free (NSF) patients. RESULTS In all, 26 patients were identified with at least 2 years of follow-up. Mean age was 43.8 years ± 11.6 years, and 46.2% were female. After a mean follow-up time of 42.9 months (range, 24.3-58.8 months), 61.5% (16/26) were free of disabling seizures, and 26.9% (7/26) had only rare disabling seizures. Whereas seizure-freedom rates between patients with and without mesial temporal sclerosis (MTS) were not statistically different (68% vs. 43%, P = 0.23), NSF patients without MTS had a shorter median time to first seizure than did NSF patients with MTS (0.55 month vs. 10 months, log-rank test P = 0.007). Postoperative complications occurred in 2 patients (7.7%), consisting of 1 permanent and 1 transient homonymous hemianopia. CONCLUSIONS LITT appears to be a safe and effective initial surgical option for treatment-resistant MTE. Among patients who have seizures after treatment, those without MTS appear to have seizures earlier than those with MTS.
Research Interests:
Research Interests:
Research Interests:
This is a zip file containing the example data for nSTAT matlab toolbox (http://doi.org/10.1016/j.jneumeth.2012.08.009) . The data directory should be un-zipped into the main nSTAT directory. Updated 7-2-2017
Research Interests:
Research Interests:
Research Interests:
ABSTRACT Introduction: Optimal gain of upper limb (UL) function is pivotal for people with stroke in order to carry out functional activities. However, half of the people surviving stroke remain with some form of UL impairment. Robot... more
ABSTRACT Introduction: Optimal gain of upper limb (UL) function is pivotal for people with stroke in order to carry out functional activities. However, half of the people surviving stroke remain with some form of UL impairment. Robot Therapy (RT) is one technique that can increase the intensity of rehabilitation and evidence shows that robot-assisted arm training results in improved short- and long-term arm strength and function of people with stroke. RT has also been combined with a non-invasive method of brain stimulation, transcranial Direct Current Stimulation (tDCS). The pilot study by Hesse et al. (2007) suggests that using both RT and tDCS results in short-term UL motor recovery of people with sub-acute stroke however, long-term and neurophysiological measurements were not involved in this study. Main Objective: To develop a protocol exploring the effectiveness and short- and long-term neural changes of tDCS and robot therapy on UL impairment and function of people with sub-acute stroke. Methods: An systematic literature review was carried out investigating different methodologies used for applying tDCS and RT, leading to the finalised protocol. Results: A pilot, double-blinded randomised controlled trial will be carried out involving two groups: 1) Armeo RT and active tDCS, and 2) Armeo RT and sham tDCS with 20 participants with sub-acute stroke in each group. Active or sham tDCS will be delivered before RT. In total, participants will receive 18 hours of RT and tDCS, spread out over 8 weeks. Clinical and neurophysiological measures using Transcranial Magnetic Stimulation will be utilised pre- and post- intervention and at 3 month follow-up. Conclusions: Research into non-invasive brain stimulation and RT seems promising but to translate research findings into clinical stroke practice, further research is needed. In the upcoming months, the aforementioned trial will be initiated which will add to the body of knowledge of neurorehabilitation research.
Research Interests: Engineering, Psychology, Music Therapy, Neurophysiology, Medicine, and 15 moreMultidisciplinary, Physical Medicine and Rehabilitation, Brain Mapping, Brain, Humans, Animals, Neuronal Plasticity, PLoS one, Clinical Neurophysiology, Questionnaires, Analysis of Variance, Functional Neuroimaging, Individualized Medicine, Psychology and Cognitive Sciences, and Medical and Health Sciences
BackgroundMagnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are... more
BackgroundMagnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are variable and long-term durability is largely unproven. Anterior temporal lobectomy (ATL) remains an option for patients with MRgLITT treatment failure. However, the safety and efficacy of this staged strategy is unknown.MethodsThis multicentre, retrospective cohort study included 268 patients consecutively treated with mesial temporal MRgLITT at 11 centres between 2012 and 2018. Seizure outcomes and complications of MRgLITT and any subsequent surgery are reported. Predictive value of preoperative variables for seizure outcome was assessed.ResultsEngel I seizure freedom was achieved in 55.8% (149/267) at 1 year, 52.5% (126/240) at 2 years and 49.3% (132/268) at the last follow-up ≥1 year (median 47 months). Engel I or II outcomes were achieved in 74.2% (...
Research Interests:
This scientific commentary refers to ‘Multisite thalamic recordings to characterize seizure propagation in the human brain’ by Wu et al. (https://doi.org/10.1093/brain/awad121).
Research Interests:
OBJECTIVE Cerebral palsy (CP) represents the most common childhood physical disability that encompasses disorders of movement and posture attributed to nonprogressive disturbances that occurred in the developmental fetal or infant brain.... more
OBJECTIVE Cerebral palsy (CP) represents the most common childhood physical disability that encompasses disorders of movement and posture attributed to nonprogressive disturbances that occurred in the developmental fetal or infant brain. Dyskinetic CP (DCP), the second most common type of CP after spastic forms, refers to a subset of patients in whom dystonia and choreoathetosis are the predominant motor manifestations. Most children with CP have abnormal brain MRI studies indicative of cortical and deep gray matter damage consistent with hypoxic ischemic encephalopathy, which may preclude or suggest decreased efficacy of standard deep brain stimulation (DBS) targets. The cerebellum has been posited as an attractive target for treatment of DCP because it is frequently spared from hypoxic ischemic damage and has shown promise in alleviating patient symptoms both in early work in the 1970s and in more recent case series with DBS. METHODS The authors performed bilateral cerebellar DBS ...
Research Interests:
OBJECTIVE Recent trends have moved from subdural grid electrocorticography (ECoG) recordings toward stereo-electroencephalography (SEEG) depth electrodes for intracranial localization of seizures, in part because of perceived morbidity... more
OBJECTIVE Recent trends have moved from subdural grid electrocorticography (ECoG) recordings toward stereo-electroencephalography (SEEG) depth electrodes for intracranial localization of seizures, in part because of perceived morbidity from subdural grid and strip electrodes. For invasive epilepsy monitoring, the authors describe the outcomes of a hybrid approach, whereby patients receive a combination of subdural grids, strips, and frameless stereotactic depth electrode implantations through a craniotomy. Evolution of surgical techniques was employed to reduce complications. In this study, the authors review the surgical hemorrhage and functional outcomes of this hybrid approach. METHODS A retrospective review was performed of consecutive patients who underwent hybrid implantation from July 2012 to May 2022 at an academic epilepsy center by a single surgeon. Outcomes included hemorrhagic and nonhemorrhagic complications, neurological deficits, length of monitoring, and number of el...
Research Interests:
Objective The objective of this study was to develop a portable and modular brain–computer interface (BCI) software platform independent of input and output devices. We implemented this platform in a case study of a subject with cervical... more
Objective The objective of this study was to develop a portable and modular brain–computer interface (BCI) software platform independent of input and output devices. We implemented this platform in a case study of a subject with cervical spinal cord injury (C5 ASIA A). Background BCIs can restore independence for individuals with paralysis by using brain signals to control prosthetics or trigger functional electrical stimulation. Though several studies have successfully implemented this technology in the laboratory and the home, portability, device configuration, and caregiver setup remain challenges that limit deployment to the home environment. Portability is essential for transitioning BCI from the laboratory to the home. Methods The BCI platform implementation consisted of an Activa PC + S generator with two subdural four-contact electrodes implanted over the dominant left hand-arm region of the sensorimotor cortex, a minicomputer fixed to the back of the subject’s wheelchair, a...
Research Interests:
Research Interests:
La presente invention concerne un systeme d'entrainement robotise pour reeducation de la marche destine a traiter les deviations secondaires de la marche, telles que l'elevation de la hanche. Un ensemble actionnement suit les... more
La presente invention concerne un systeme d'entrainement robotise pour reeducation de la marche destine a traiter les deviations secondaires de la marche, telles que l'elevation de la hanche. Un ensemble actionnement suit les mouvements naturels du bassin d'un utilisateur, tout en appliquant des moments correcteurs a l'asymetrie du bassin. Une interface homme-robot, sous la forme d'un exosquelette de corps inferieur, est prevue pour ameliorer le transfert de moments correcteurs au bassin. Ledit systeme comprend un systeme de commande d'impedance incorporant une fonctionnalite de retroaction, qui permet de moduler les forces appliquees sur le corps en fonction des efforts du patient. L'invention porte egalement sur divers protocoles pour l'utilisation du systeme.
Research Interests:
Research Interests:
Objective: To report a case of multiple ischemic strokes secondary to cerebral AVM vascular steal phenomenon. Background: An arteriovenous malformation (AVM) is an abnormal connection between an artery and a vein. There have been... more
Objective: To report a case of multiple ischemic strokes secondary to cerebral AVM vascular steal phenomenon. Background: An arteriovenous malformation (AVM) is an abnormal connection between an artery and a vein. There have been conflicting opinions about the in vivo existence of vascular steal phenomenon associated with cerebral AVM manifesting as focal neurological deficits. We present a case of multiple acute infarcts which may have been secondary to a vascular steal phenomenon due to the presence of the cerebral AVM. Design/Methods: Retrospective Chart review. Results: Case Description: 51-year-old right handed male with multiple cardiovascular risk factors and a known old right temporo-parietal AVM presented with new onset (>6h) left hemiparesis and dysarthria. His vital signs were unremarkable and his neurological exam demonstrated an upper motor neuron left facial palsy and left hemiparesis (MRC grade 3/5). MRI brain showed a large right hemispheric AVM and multiple corti...
Research Interests:
Objective. Automatic detection of interictal epileptiform discharges (IEDs, short as ‘spikes’) from an epileptic brain can help predict seizure recurrence and support the diagnosis of epilepsy. Developing fast, reliable and robust... more
Objective. Automatic detection of interictal epileptiform discharges (IEDs, short as ‘spikes’) from an epileptic brain can help predict seizure recurrence and support the diagnosis of epilepsy. Developing fast, reliable and robust detection methods for IEDs based on scalp or intracranial electroencephalogram (iEEG) may facilitate online seizure monitoring and closed-loop neurostimulation. Approach. We developed a new deep learning approach, which employs a long short-term memory network architecture (‘IEDnet’) and an auxiliary classifier generative adversarial network (AC-GAN), to train on both expert-annotated and augmented spike events from iEEG recordings of epilepsy patients. We validated our IEDnet with two real-world iEEG datasets, and compared IEDnet with the support vector machine (SVM) and random forest (RF) classifiers on their detection performances. Main results. IEDnet achieved excellent cross-validated detection performances in terms of both sensitivity and specificity...
Research Interests:
Research Interests:
Subsensory noise stimulation targeting sensory receptors has been shown to improve balance control in healthy and impaired individuals. However, the potential for application of this technique in other contexts is still unknown. Gait... more
Subsensory noise stimulation targeting sensory receptors has been shown to improve balance control in healthy and impaired individuals. However, the potential for application of this technique in other contexts is still unknown. Gait control and adaptation rely heavily on the input from proprioceptive organs in the muscles and joints. Here we investigated the use of subsensory noise stimulation as a means to influence motor control by “boosting” proprioception during locomotor adaptations to forces delivered by a robot. The forces increase step length unilaterally and trigger an adaptive response that restores the original symmetry. Healthy participants performed two adaptation experiments, one with stimulation applied to the hamstring muscles and one without. We found that participants adapted faster but to a lesser extent when undergoing subsensory stimulation. We argue that this behaviour is due to the dual effect that the stimulation has on the afferents encoding position and ve...
Research Interests:
Research Interests:
BACKGROUND Peripheral nerve sheath tumors (PNSTs) are tumors with unique clinical and imaging features that present to a variety of physicians. These lesions are often referred for biopsy, which can put nerve fascicles at risk.... more
BACKGROUND Peripheral nerve sheath tumors (PNSTs) are tumors with unique clinical and imaging features that present to a variety of physicians. These lesions are often referred for biopsy, which can put nerve fascicles at risk. Preoperative biopsy may cause distortion of normal anatomic planes, making definitive resection difficult. OBJECTIVE To evaluate the neurological risks of preoperative biopsy in benign PNSTs. METHODS Surgical cases collected retrospectively using a prospectively established database of PNSTs treated by a single surgeon between 1997 and 2019. Patients were dichotomized depending on preoperative biopsy. The effects of biopsy were assessed via history and physical examination both pre- and postdefinitive resection. RESULTS A total of 151 cases were included. Only 23.2% (35) of patients underwent preoperative biopsy, but 42.9% of these experienced new or worsening neurological examination immediately following biopsy. After definitive resection, the rate of neuro...
Research Interests:
Postsurgical seizure outcome following laser interstitial thermal therapy (LiTT) for the management of drug-resistant mesial temporal lobe epilepsy (MTLE) has been limited to 2 years. Furthermore, its impact on presurgical mood and... more
Postsurgical seizure outcome following laser interstitial thermal therapy (LiTT) for the management of drug-resistant mesial temporal lobe epilepsy (MTLE) has been limited to 2 years. Furthermore, its impact on presurgical mood and anxiety disorders has not been investigated. The objectives of this study were (1) to identify seizure outcome changes over a period ranging from 18 to 81 months; (2) to investigate the seizure-free rate in the last follow-up year; (3) to identify the variables associated with seizure freedom; and (4) to identify the impact of LiTT on presurgical mood and anxiety disorders. Medical records of all patients who underwent LiTT for MTLE from 2013 to 2019 at the University of Miami Comprehensive Epilepsy Center were retrospectively reviewed. Demographic, epilepsy-related, cognitive, psychiatric, and LiTT-related data were compared between seizure-free (Engel Class I) and non-seizure-free (Engel Class II + III + IV) patients. Statistical analyses included univariate and multivariate stepwise logistic regression analyses. Forty-eight patients (mean age = 43 ± 14.2 years, range = 21-78) were followed for a mean period of 50 ± 20.7 months (range = 18-81); 29 (60.4%) achieved an Engel Class I outcome, whereas 11 (22.9%) had one to three seizures/year. Seizure-freedom rate decreased from 77.8% to 50% among patients with 24- and >61-month follow-up periods, respectively. In the last follow-up year, 83% of all patients were seizure-free. Seizure freedom was associated with having mesial temporal sclerosis (MTS), no presurgical focal to bilateral tonic-clonic seizures, and no psychopathology in the last follow-up year. Presurgical mood and/or anxiety disorder were identified in 30 patients (62.5%) and remitted after LiTT in 19 (62%). LiTT appears to be a safe and effective surgical option for treatment-resistant MTLE, particularly among patients with MTS. Remission of presurgical mood and anxiety disorders can also result from LiTT.
Research Interests:
OBJECTIVE Motor vehicle collisions (MVCs) account for 1.35 million deaths and cost $518 billion US dollars each year worldwide, disproportionately affecting young patients and low-income nations. The ability to successfully anticipate... more
OBJECTIVE Motor vehicle collisions (MVCs) account for 1.35 million deaths and cost $518 billion US dollars each year worldwide, disproportionately affecting young patients and low-income nations. The ability to successfully anticipate clinical outcomes will help physicians form effective management strategies and counsel families with greater accuracy. The authors aimed to train several classifiers, including a neural network model, to accurately predict MVC outcomes. METHODS A prospectively maintained database at a single institution’s level I trauma center was queried to identify all patients involved in MVCs over a 20-year period, generating a final study sample of 16,287 patients from 1998 to 2017. Patients were categorized by in-hospital mortality (during admission) and length of stay (LOS), if admitted. All models included age (years), Glasgow Coma Scale (GCS) score, and Injury Severity Score (ISS). The in-hospital mortality and hospital LOS models further included time to adm...
Research Interests:
Research Interests:
The impact of various types of spinal surgeries on sexual health and post-operative sexual activity is a common question among both patients and healthcare professionals. Unfortunately, there is no clear answer to this question in the... more
The impact of various types of spinal surgeries on sexual health and post-operative sexual activity is a common question among both patients and healthcare professionals. Unfortunately, there is no clear answer to this question in the scientific literature. OBJECT Our goal was to survey the current practices and recommendations of Neurosurgeons to see if there was a clinical consensus. METHODS Participants in the survey included 50 Spine Surgeons: 47 males and 3 females. The average age of the participants was 45.7 years old and the number of years of practice after residency was on average 11.7 years. Additional survey questions included the number of weeks recommended for patients to abstain prior to returning to sexual activity after specified small, medium and large spinal surgeries. RESULTS We found that there were no statically significant correlations between the participants' ages or years post-residency and the time response for post-operative return to sexual activity. Some answers were significantly different amongst the participants. The results also showed a trend for spine surgeons to recommend longer intervals for return to sexual activities after more involved surgical procedures. CONCLUSION The survey results and comments demonstrate the complete lack of physician consensus regarding recommendations for post-operative return to sexual activity and the need for further study.
Research Interests:
BackgroundFreezing of gait (FOG) is a debilitating motor deficit in a subset of Parkinson’s Disease (PD) patients that is poorly responsive to levodopa or deep brain stimulation (DBS) of established PD targets. The proposal of a DBS... more
BackgroundFreezing of gait (FOG) is a debilitating motor deficit in a subset of Parkinson’s Disease (PD) patients that is poorly responsive to levodopa or deep brain stimulation (DBS) of established PD targets. The proposal of a DBS target in the midbrain, known as the pedunculopontine nucleus (PPN), to address FOG was based on its observed neuropathology in PD and its hypothesized involvement in locomotor control as a part of the mesencephalic locomotor region (MLR). Initial reports of PPN DBS were met with enthusiasm; however, subsequent studies reported mixed results. A closer review of the MLR basic science literature, suggests that the closely related cuneiform nucleus (CnF), dorsal to the PPN, may be a superior site to promote gait. Although suspected to have a conserved role in the control of gait in humans, deliberate stimulation of a homolog to the CnF in humans using directional DBS electrodes has not been attempted.MethodsAs part of an open-label Phase 1 clinical study, o...
Research Interests:
Background Poor prognosis of glioblastoma patients and the extensive heterogeneity of glioblastoma at both the molecular and cellular level necessitates developing novel individualized treatment modalities via genomics-driven approaches.... more
Background Poor prognosis of glioblastoma patients and the extensive heterogeneity of glioblastoma at both the molecular and cellular level necessitates developing novel individualized treatment modalities via genomics-driven approaches. Methods This study leverages numerous pharmacogenomic and tissue databases to examine drug repositioning for glioblastoma. RNAseq of glioblastoma tumor samples from The Cancer Genome Atlas (TCGA, n=117) were compared to “normal” frontal lobe samples from Genotype-Tissue Expression Portal (GTEX, n=120) to find differentially expressed genes (DEGs). Using compound-gene expression data and drug activity data from the Library of Integrated Network-Based Cellular Signatures (LINCS, n=66,512 compounds) CCLE (71 glioma cell lines), and Chemical European Molecular Biology Laboratory (ChEMBL) platforms, we employed a summarized reversal gene expression metric (sRGES) to “reverse” the resultant disease signature for GBM and its subtypes. A multi-parametric st...
Research Interests:
Over 15 million epilepsy patients worldwide have medically refractory epilepsy (MRE), i.e., they do not respond to anti-epileptic drugs. Successful surgery is a hopeful alternative for seizure freedom but can only be achieved through... more
Over 15 million epilepsy patients worldwide have medically refractory epilepsy (MRE), i.e., they do not respond to anti-epileptic drugs. Successful surgery is a hopeful alternative for seizure freedom but can only be achieved through complete resection or disconnection of the epileptogenic zone (EZ), the brain region(s) where seizures originate. Unfortunately, surgical success rates vary between 30%-70% because no clinically validated biological markers of the EZ exist. Localizing the EZ has thus become a costly and time-consuming process during which a team of clinicians obtain non-invasive neuroimaging data, which is often followed by invasive monitoring involving days-to-weeks of EEG recordings captured intracranially (iEEG). Clinicians visually inspect iEEG data, looking for abnormal activity (e.g., low-voltage high frequency activity) on individual channels occurring immediately before seizures. They also look for abnormal spikes that occur on iEEG between seizures (“resting-st...
Research Interests:
OBJECTIVE Timely ventriculostomy placement is critical in the management of neurosurgical emergencies. Prompt external ventricular drain (EVD) placement has been shown to improve long-term patient outcomes and decrease the length of ICU... more
OBJECTIVE Timely ventriculostomy placement is critical in the management of neurosurgical emergencies. Prompt external ventricular drain (EVD) placement has been shown to improve long-term patient outcomes and decrease the length of ICU and hospital stays. Successful and efficient EVD placement requires seamless coordination among multiple healthcare teams. In this study, the authors sought to identify factors favoring delayed ventriculostomy via a quality improvement initiative and to implement changes to expedite EVD placement. METHODS Through process mapping, root cause analysis, and interviews with staff, the authors identified the lack of a standardized mechanism for alerting necessary healthcare teams as a major contributor to delays in EVD placement. In December 2019, an EVD alert system was developed to automatically initiate an EVD placement protocol and to alert the neurosurgery department, pharmacy, core laboratory, and nursing staff to prepare for EVD placement. The time...
Research Interests:
Several new approaches for treatment of Central Nervous System (CNS) disorders are currently under investigation, including the use of rehabilitation training strategies, which are often combined with electrical and/or pharmacological... more
Several new approaches for treatment of Central Nervous System (CNS) disorders are currently under investigation, including the use of rehabilitation training strategies, which are often combined with electrical and/or pharmacological modulation of spinal locomotor circuitries. While these approaches show great promise in the laboratory setting, there still exists a large gap in knowledge on how to transfer these treatments to daily clinical use. This thematic series presents a cross section of cutting edge approaches with the goal of transferring basic neuroscience principles from the laboratory to the proverbial "bedside".
Research Interests:
Keeping cognitive stress at a healthy range can improve the overall quality of life: helping subjects to decrease their high levels of arousal, which will make them relaxed, and elevate their low levels of arousal, which could increase... more
Keeping cognitive stress at a healthy range can improve the overall quality of life: helping subjects to decrease their high levels of arousal, which will make them relaxed, and elevate their low levels of arousal, which could increase their engagement. With recent advances in wearable technologies, collected skin conductance data provides us with valuable information regarding ones’ cognitive stress-related state. In this research, we aim to create a simulation environment to control a cognitive stress-related state in a closed-loop manner. Toward this goal, by analyzing the collected skin conductance data from different subjects, we model skin conductance response events as a function of simulated environmental stimuli associated with cognitive stress and relaxation. Then, we estimate the hidden stress-related state by employing Bayesian filtering. Finally, we design a fuzzy control structure to close the loop in the simulation environment. Particularly, we design two classes of c...
Research Interests:
Research Interests:
OBJECTIVE Cerebral extracranial-intracranial (EC-IC) direct bypass is a commonly used procedure for ischemic vasculopathy. A previously described variation of this technique is to utilize one donor artery to supply two recipient arteries,... more
OBJECTIVE Cerebral extracranial-intracranial (EC-IC) direct bypass is a commonly used procedure for ischemic vasculopathy. A previously described variation of this technique is to utilize one donor artery to supply two recipient arteries, which the authors designate as 1D2R. The purpose of this study is to present a single surgeon’s series of 1D2R direct bypasses for moyamoya and ischemia using detailed clinical, angiographic, and intraoperative blood flow measurement data. To the authors’ knowledge, this is the largest series reported to date. METHODS Hospital, office, and radiographic imaging records for all patients who underwent cerebral revascularization using a 1D2R bypass by the senior author were reviewed. The patients’ demographic information, clinical presentation, associated medical conditions, intraoperative information, and postoperative course were obtained from reviewing the medical records. RESULTS A total of 21 1D2R bypasses were performed in 19 patients during the ...
Research Interests:
Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in one 21 year-old male subject with complete cervical quadriplegia (C5... more
Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in one 21 year-old male subject with complete cervical quadriplegia (C5 American Spinal Injury Association Impairment Scale A) using a portable fully implanted brain-computer interface within the home environment. The brain-computer interface consists of subdural surface electrodes placed over the dominant-hand motor cortex and connects to a transmitter implanted subcutaneously below the clavicle, which allows continuous reading of the electrocorticographic activity. Movement-intent was used to trigger functional electrical stimulation of the dominant hand during an initial 29-week laboratory study and subsequently via a mechanical hand orthosis during in-home use. Movement intent information could be decoded consistently throughout the 29-week in-laboratory study with a mean accuracy of 89.0% (range 78–93.3%). Improvem...
Research Interests:
Background: Minimizing time-to-external ventricular drain (EVD) placement in the emergency department (ED) is critical. We sought to understand factors affecting time-to-EVD placement through a quality improvement initiative. Methods: The... more
Background: Minimizing time-to-external ventricular drain (EVD) placement in the emergency department (ED) is critical. We sought to understand factors affecting time-to-EVD placement through a quality improvement initiative. Methods: The use of process mapping, root cause analyses, and interviews with staff revealed decentralized supply storage as a major contributor to delays in EVD placement. We developed an EVD “crash cart” as a potential solution to this problem. Time-to-EVD placement was tracked prospectively using time stamps in the electronic medical record (EMR); precart control patients were reviewed retrospectively. Results: The final cohorts consisted of 33 precart and 18 postcart cases. The mean time-to-EVD in the precart group was 99.09 min compared to 71.88 min in the postcart group (two-tailed t-test, P = 0.023). Median time-to-EVD was 92 min in the precart group compared to 64 min in the postcart group (rank sum test, P = 0.0165). Postcart patients trended toward im...
Research Interests:
BACKGROUND Pyogenic spondylodiscitis diminishes spinal structural integrity via disruption of the anterior and middle column, sometimes further compounded by iatrogenic violation of the posterior tension band during initial posterior... more
BACKGROUND Pyogenic spondylodiscitis diminishes spinal structural integrity via disruption of the anterior and middle column, sometimes further compounded by iatrogenic violation of the posterior tension band during initial posterior decompressive surgeries. Although medical management is typically sufficient, refractory infection or progressive deformity may require aggressive debridement and reconstructive arthrodesis. Although anterior debridement plus reconstruction with posterior stabilization is an effective treatment option, existing techniques have limited efficacy for correcting focal deformity, leaving patients at risk for long-term sagittal imbalance, pain, and disability. OBSERVATIONS The authors present a case of chronic lumbar pyogenic spondylodiscitis in a patient in whom initial surgical debridement failed and pronounced angular kyphosis and intractable low back pain developed. A novel bipedicular handlebar construct was used to achieve angular correction of the kyph...
Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in a subject with complete cervical quadriplegia (C5 ASIA Impairment... more
Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in a subject with complete cervical quadriplegia (C5 ASIA Impairment Scale A) using a portable fully implanted brain-computer interface (BCI) within the home environment. The BCI consists of subdural surface electrodes placed over the dominant-hand motor cortex and connects to a transmitter implanted subcutaneously below the clavicle, which allows continuous reading of the electrocorticographic (ECoG) activity. Movement-intent was used to trigger functional electrical stimulation (FES) of the dominant hand during an initial 29-week laboratory study and subsequently via a mechanical hand orthosis during in-home use. Movement intent information could be decoded consistently throughout the 29-week in-laboratory study with a mean accuracy of 89.0% (range 78-93.3%). Improvements were observed in both the speed and accuracy o...