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1.
Spinal Cord Ser Cases ; 8(1): 66, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35831274

RESUMO

INTRODUCTION: Post-traumatic syringomyelia is an uncommon complication after traumatic spinal cord injury. This case study details our decision-making and surgical approach for a patient with symptomatic post-traumatic syringomyelia after sustaining a gunshot wound. CASE PRESENTATION: A 24-year-old man with past medical history of distant American Spinal Injury Association Impairment Grade B spinal cord injury due to ballistic injury developed delayed post-traumatic syringomyelia, resulting in unilateral sensory loss and left upper extremity weakness. CT and MR imaging revealed a syrinx spanning his cervical and thoracic spine causing significant spinal cord compression. To relieve achieve decompression and restore CSF flow dynamics, we performed a bony extradural decompression, bullet fragment extraction, spinal cord untethering, and midline myelotomy. Postoperatively, the patient demonstrated clinical and radiographical improvement. DISCUSSION: Post-traumatic syringomyelia is potentially morbid sequalae of spinal cord injuries. Suspicion for post-traumatic syringomyelia should be maintained in patients with delayed, progressive neurologic deficits. In this setting, surgical intervention may require extradural and intradural procedures to mitigate neural compression along the dilated central canal by the syrinx.


Assuntos
Traumatismos da Medula Espinal , Traumatismos da Coluna Vertebral , Siringomielia , Ferimentos por Arma de Fogo , Adulto , Humanos , Masculino , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/cirurgia , Traumatismos da Coluna Vertebral/complicações , Siringomielia/diagnóstico por imagem , Siringomielia/etiologia , Siringomielia/cirurgia , Ferimentos por Arma de Fogo/complicações , Ferimentos por Arma de Fogo/cirurgia , Adulto Jovem
2.
J Neurosurg ; 137(6): 1601-1609, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35535837

RESUMO

OBJECTIVE: Piriform cortex (PC) is one of the critical structures in the epileptogenesis of mesial temporal lobe epilepsy (mTLE), but its role is poorly understood. The authors examined the utility of apparent diffusion coefficient (ADC; an MR-based marker of tissue pathology) of the PC as a predictor of seizure outcome in patients with mTLE undergoing MR-guided laser interstitial thermal therapy (MRgLITT). METHODS: A total of 33 patients diagnosed with mTLE who underwent MRgLITT at the authors' institution were included in the study. The 6-month postoperative seizure outcomes were classified using the International League Against Epilepsy (ILAE) system as good (complete seizure freedom, ILAE class I) and poor (seizure present, ILAE classes II-VI). The PC and ablation volumes were manually segmented from both the preoperative and intraoperative MRI sequences, respectively. The mean ADC intensities of 1) preablation PC; 2) total ablation volume; 3) ablated portion of PC; and 4) postablation residual PC were calculated and compared between good and poor outcome groups. Additionally, the preoperative PC volumes and proportion of PC volume ablated were examined and compared between the subjects in the two outcome groups. RESULTS: The mean age at surgery was 36.5 ± 3.0 years, and the mean follow-up duration was 1.9 ± 0.2 years. Thirteen patients (39.4%) had a good outcome. The proportion of PC ablated was significantly associated with seizure outcome (10.16 vs 3.30, p < 0.05). After accounting for the variability in diffusion tensor imaging acquisition parameters, patients with good outcome had a significantly higher mean ADC of the preablation PC (0.3770 vs -0.0108, p < 0.05) and the postoperative residual PC (0.4197 vs 0.0309, p < 0.05) regions compared to those with poor outcomes. No significant differences in ADC of the ablated portion of PC were observed (0.2758 vs -0.4628, p = 0.12) after performing multivariate analysis. CONCLUSIONS: A higher proportion of PC ablated was associated with complete seizure freedom. Preoperative and postoperative residual ADC measures of PC were significantly higher in the good seizure outcome group in patients with mTLE who underwent MRgLITT, suggesting that ADC analysis can assist with postablation outcome prediction and patient stratification.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Epilepsia , Terapia a Laser , Córtex Piriforme , Humanos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Imagem de Tensor de Difusão , Terapia a Laser/métodos , Convulsões/diagnóstico por imagem , Convulsões/etiologia , Convulsões/cirurgia , Imageamento por Ressonância Magnética/métodos , Epilepsia/cirurgia , Lasers , Resultado do Tratamento , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia
3.
J Spec Oper Med ; 22(2): 55-61, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35639895

RESUMO

Traumatic brain injury (TBI) management is complex. The brain is a sensitive, high-maintenance organ that loses its ability to take care of itself upon injury, and our primary mission is to achieve and maintain optimal levels of cerebral blood flow (CBF) from the moment of injury until recovery. The authors provide a case and discuss prehospital patient management, including adequate oxygen saturation and blood pressure, early recognition of TBI, frequent exams, detailed charting and hand-off, and fast transport to the next echelon of care.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Serviços Médicos de Emergência , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/terapia , Circulação Cerebrovascular/fisiologia , Humanos
4.
Neurosurgery ; 91(3): 414-421, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35593730

RESUMO

BACKGROUND: Growing evidence suggests that piriform cortex resection during anterior temporal lobectomy is important for achieving good seizure outcome in mesial temporal lobe epilepsy (mTLE). However, the relationship between seizure outcome and piriform cortex ablation during MR-guided laser interstitial thermal therapy (MRgLITT) remains unclear. OBJECTIVE: To determine whether ablation of piriform cortex was associated with seizure outcome in patients with mTLE undergoing MRgLITT. METHODS: We performed preablation and postablation volumetric analyses of hippocampus, amygdala, piriform cortex, and ablation volumes in patients with mTLE who underwent MRgLITT at our institution from 2014 to 2019. RESULTS: Thirty nine patients with mTLE were analyzed. In univariate logistic regression, percent piriform cortex ablation was associated with International League Against Epilepsy (ILAE) class 1 at 6 months (odds ratio [OR] 1.051, 95% CI [1.001-1.117], P = .045), whereas ablation volume, percent amygdala ablation, and percent hippocampus ablation were not ( P > .05). At 1 year, ablation volume was associated with ILAE class 1 (OR 1.608, 95% CI [1.071-2.571], P = .021) while percent piriform cortex ablation became a trend (OR 1.050, 95% CI [0.994-1.109], P = .054), and both percent hippocampus ablation and percent amygdala ablation were not significantly associated with ILAE class 1 ( P > .05). In multivariable logistic regression, only percent piriform cortex ablation was a significant predictor of seizure freedom at 6 months (OR 1.085, 95% CI [1.012-1.193], P = .019) and at 1 year (OR 1.074, 95% CI [1.003-1.178], P = .041). CONCLUSION: Piriform cortex ablation volume is associated with seizure outcome in patients with mTLE undergoing MRgLITT. The piriform cortex should be considered a high yield ablation target to achieve good seizure outcome.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Terapia a Laser , Córtex Piriforme , Tonsila do Cerebelo/cirurgia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/diagnóstico por imagem , Hipocampo/cirurgia , Humanos , Imageamento por Ressonância Magnética , Convulsões/complicações , Convulsões/cirurgia , Resultado do Tratamento
6.
Brain Stimul ; 15(1): 152-163, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34856396

RESUMO

BACKGROUND: Phase-amplitude coupling (PAC) in which the amplitude of a faster field potential oscillation is coupled to the phase of a slower rhythm, is one of the most well-studied interactions between oscillations at different frequency bands. In a healthy brain, PAC accompanies cognitive functions such as learning and memory, and changes in PAC have been associated with neurological diseases including Parkinson's disease (PD), schizophrenia, obsessive-compulsive disorder, Alzheimer's disease, and epilepsy. OBJECTIVE: /Hypothesis: In PD, normalization of PAC in the motor cortex has been reported in the context of effective treatments such as dopamine replacement therapy and deep brain stimulation (DBS), but the possibility of normalizing PAC through intervention at the cortex has not been shown in humans. Phase-targeted stimulation (PDS) has a strong potential to modulate PAC levels and potentially normalize it. METHODS: We applied stimulation pulses triggered by specific phases of the beta oscillations, the low frequency oscillations that define phase of gamma amplitude in beta-gamma PAC, to the motor cortex of seven PD patients at rest during DBS lead placement surgery We measured the effect on PAC modulation in the motor cortex relative to stimulation-free periods. RESULTS: We describe a system for phase-targeted stimulation locked to specific phases of a continuously updated slow local field potential oscillation (in this case, beta band oscillations) prediction. Stimulation locked to the phase of the peak of beta oscillations increased beta-gamma coupling both during and after stimulation in the motor cortex, and the opposite phase (trough) stimulation reduced the magnitude of coupling after stimulation. CONCLUSION: These results demonstrate the capacity of cortical phase-targeted stimulation to modulate PAC without evoking motor activation, which could allow applications in the treatment of neurological disorders associated with abnormal PAC, such as PD.


Assuntos
Estimulação Encefálica Profunda , Córtex Motor , Doença de Parkinson , Encéfalo , Cognição , Humanos , Doença de Parkinson/terapia
7.
J Neurosurg ; : 1-7, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34891139

RESUMO

OBJECTIVE: Maximal safe ablation of target structures during magnetic resonance-guided laser interstitial thermal therapy (MRgLiTT) is critical to achieving good seizure outcome in patients with mesial temporal lobe epilepsy (mTLE). The authors sought to determine whether intraoperative physiological variables are associated with ablation volume during MRgLiTT. METHODS: Patients with mTLE who underwent MRgLiTT at our institution from 2014 to 2019 were retrospectively analyzed. Ablation volume was determined with volumetric analysis of intraoperative postablation MR images. Physiological parameters (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP], end-tidal carbon dioxide [ETCO2]) measured 40 minutes prior to ablation were analyzed. Univariate and multivariate regression analyses were performed to determine independent predictors of ablation volume. RESULTS: Forty-four patients met the inclusion criteria. The median (interquartile range) ablation volume was 4.27 (2.92-5.89) cm3, and median ablation energy was 7216 (6402-8784) J. The median MAP, SBP, DBP, and ETCO2 values measured during the 40-minute period leading up to ablation were 72.8 (66.2-81.5) mm Hg, 104.4 (96.4-114.4) mm Hg, 62.4 (54.1-69.8) mm Hg, and 34.1 (32.0-36.2) mm Hg, respectively. In univariate analysis, only total laser energy (r = 0.464, p = 0.003) and 40-minute average ETCO2 (r = -0.388, p = 0.012) were significantly associated with ablation volume. In multivariate analysis, only ETCO2 ≤ 33 mm Hg (p = 0.001) was significantly associated with ablation volume. CONCLUSIONS: Total ablation energy and ETCO2, but not blood pressure, may significantly affect ablation volume in mTLE patients undergoing MRgLiTT. Mild hypocapnia was associated with increased extent of ablation. Intraoperative monitoring and modulation of ETCO2 may help improve extent of ablation, prediction of ablation volume, and potentially seizure outcome.

8.
Neurosurgery ; 89(3): 372-382, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34098572

RESUMO

Traumatic spinal cord injury (SCI) is a common and devastating condition. In the absence of effective validated therapies, there is an urgent need for novel methods to achieve injury stabilization, regeneration, and functional restoration in SCI patients. Ultrasound is a versatile platform technology that can provide a foundation for viable diagnostic and therapeutic interventions in SCI. In particular, real-time perfusion and inflammatory biomarker monitoring, focal pharmaceutical delivery, and neuromodulation are capabilities that can be harnessed to advance our knowledge of SCI pathophysiology and to develop novel management and treatment options. Our review suggests that studies that evaluate the benefits and risks of ultrasound in SCI are severely lacking and our understanding of the technology's potential impact remains poorly understood. Although the complex anatomy and physiology of the spine and the spinal cord remain significant challenges, continued technological advances will help the field overcome the current barriers and bring ultrasound to the forefront of SCI research and development.


Assuntos
Traumatismos da Medula Espinal , Humanos , Medula Espinal , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/terapia , Coluna Vertebral
9.
J Clin Neurosci ; 84: 50-52, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33485599

RESUMO

Spinal cord stimulation (SCS) has been considered as an alternative therapy to reduce opioid requirements in certain chronic pain disorders. However, information on long-term opioid consumption patterns and their impact on SCS device explantation is lacking. We conducted a retrospective study of 45 patients to characterize long-term patterns of opioid usage after SCS implantation. Daily morphine equivalent dosage (MED) increased, decreased, and remained the same in 40%, 40%, and 20% of patients at 1-year follow-up, respectively. Twelve (27%) underwent explantation due to treatment failure at a median of 18 months after implantation. Pre-operative opioid status (naïve vs. active use) was not associated with explantation (18% vs. 29%, p = 0.699) and neither was the daily MED change status (i.e. increased, decreased, unchanged) at 1-year (p = 0.499, 1.000, 0.735, respectively). Following explantation, reduction in the daily MED was seen in 92% of patients with dosages falling below pre-operative baseline in nine. Among the opioid naïve patients, 55% were on opioids at last follow-up (average 32.4 ± 14.6 months). Our results indicate that daily opioid consumption does not decrease in most patients 1-year after SCS implantation. Furthermore, post-operative evaluation beyond 1-year is necessary to assess the efficacy and durability of SCS therapy as well as its impact on opioid requirement. Lastly, rigorous patient selection and pre-operative risk assessment for misuse and dependence are paramount to improving outcome after SCS implantation.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Crônica/terapia , Manejo da Dor/métodos , Estimulação da Medula Espinal/métodos , Idoso , Remoção de Dispositivo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tempo
10.
J Surg Educ ; 78(4): 1295-1304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33419691

RESUMO

OBJECTIVES: Hydration and nutrition are critical to achieving optimal performance. This study aimed to assess the impact of limited oral intake in the operating room environment on surgical resident health, well-being, and performance. DESIGN: Electronic survey was sent to 94 surgical trainees at our institution in 2020. Chi-square analyses were performed to assess for differences in survey responses by sex. SETTING: A single tertiary-care institution. PARTICIPANTS: Surveys were sent to surgical residents and fellows in general surgery, neurosurgery, and orthopedic surgery. Seventy-nine (80%) of the 94 residents and fellows responded. RESULTS: Of the 79 responses, most trainees (79%) experienced dehydration within 6 hours of operating. Forty-four (56%) reported no fluid intake for greater than 6 hours on average, and 39 (49%) reported that they frequently had difficulty rehydrating in between cases. Most of the respondents (70%) frequently experienced symptoms of dehydration, including orthostasis, headache, and constipation. Fifty-six (71%) believed that dehydration frequently affected their performance. Compared to men, women were more likely to feel dehydrated within 4 hours of operating (58% vs. 25%, p = 0.005). Women were also more likely to have difficulty rehydrating in between cases (75% vs. 38%, p = 0.0026), experience symptoms of dehydration (92% vs. 60%, p = 0.0049), and report that dehydration affects surgical performance (88% vs. 64%, p = 0.0318). CONCLUSIONS: Prolonged fasting and dehydration are common issues that may negatively impact performance and wellbeing of surgical trainees. Also, dehydration may affect men and women differently.


Assuntos
Internato e Residência , Neurocirurgia , Cirurgiões , Desidratação , Jejum , Feminino , Humanos , Masculino , Salas Cirúrgicas
11.
J Neurosurg Case Lessons ; 2(24): CASE21355, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-35855487

RESUMO

BACKGROUND: Intracranial deposits of fat droplets are an unusual presentation of a spinal dermoid cyst after spontaneous rupture and are even more uncommon after trauma. Here, the authors present a case with this rare clinical presentation, along with a systematic review of the literature to guide decision making in these patients. OBSERVATIONS: A 54-year-old woman with Lynch syndrome presented with severe headache and sacrococcygeal pain after a traumatic fall. Computed tomography of the head revealed multifocal intraventricular and intracisternal fat deposits, which were confirmed by magnetic resonance imaging (MRI) of the neuroaxis; in addition, a ruptured multiloculated cyst was identified within the sacral canal with proteinaceous/hemorrhagic debris, most consistent with a sacral dermoid cyst with rupture into the cerebrospinal fluid (CSF) space. An unruptured sacral cyst was later noted on numerous previous MRI scans. In our systematic review, we identified 20 similar cases, most of which favored surgical treatment. LESSONS: Rupture of an intraspinal dermoid cyst must be considered when intracranial fat deposits are found in the context of cauda equina syndrome, meningism, or hydrocephalus. Complete tumor removal with close postoperative follow-up is recommended to decrease the risk of complications. CSF diversion must be prioritized if life-threatening hydrocephalus is present.

12.
Br J Neurosurg ; 35(3): 301-305, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32648480

RESUMO

BACKGROUND: Deep brain stimulation (DBS) lead revision due to suboptimal therapy is common but there is no standardised protocol. We describe a novel technique using iMRI to perform concurrent new Globus Pallidus Internus (GPi) DBS lead implantation and old lead removal in a dystonia patient.Case-description: A 60-year-old woman with medication and neurotoxin-refractory isolated cervical dystonia underwent awake bilateral GPi DBS surgery with MER-guided lead implantation. She initially had a favourable response but later reported suboptimal benefit despite reprogramming. MRI demonstrated suboptimal lead placement and MRI-guided revision surgery under general anesthesia was planned. The goal was to place new leads superior and medial to the existing leads. Using a 1.5 T iMRI and the ClearPoint® NeuroNavigation system, new leads were placed through the existing burr holes, into the new targets with radial errors < 0.08mm bilaterally without crossing the old leads. The old leads were then removed and the new leads connected to the existing pulse generator. The patient tolerated the procedure well and had improved side-effect profile at all contacts at 1-month follow-up. CONCLUSIONS: Non-staged iMRI-guided DBS revision surgery under general anesthesia is technically feasible and is an alternative strategy to a staged iMRI-guided revision surgery or an awake MER-guided revision surgery in select patients.


Assuntos
Estimulação Encefálica Profunda , Distonia , Feminino , Globo Pálido/cirurgia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Front Neurosci ; 14: 558967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132822

RESUMO

Deep brain stimulation (DBS) is an effective surgical therapy for Parkinson's disease (PD). However, limitations of the DBS systems have led to great interest in adaptive neuromodulation systems that can dynamically adjust stimulation parameters to meet concurrent therapeutic demand. Constant high-frequency motor cortex stimulation has not been remarkably efficacious, which has led to greater focus on modulation of subcortical targets. Understanding of the importance of timing in both cortical and subcortical stimulation has generated an interest in developing more refined, parsimonious stimulation techniques based on critical oscillatory activities of the brain. Concurrently, much effort has been put into identifying biomarkers of both parkinsonian and physiological patterns of neuronal activities to drive next generation of adaptive brain stimulation systems. One such biomarker is beta-gamma phase amplitude coupling (PAC) that is detected in the motor cortex. PAC is strongly correlated with parkinsonian specific motor signs and symptoms and respond to therapies in a dose-dependent manner. PAC may represent the overall state of the parkinsonian motor network and have less instantaneously dynamic fluctuation during movement. These findings raise the possibility of novel neuromodulation paradigms that are potentially less invasiveness than DBS. Successful application of PAC in neuromodulation may necessitate phase-dependent stimulation technique, which aims to deliver precisely timed stimulation pulses to a specific phase to predictably modulate to selectively modulate pathological network activities and behavior in real time. Overcoming current technical challenges can lead to deeper understanding of the parkinsonian pathophysiology and development of novel neuromodulatory therapies with potentially less side-effects and higher therapeutic efficacy.

14.
Curr Neurol Neurosci Rep ; 20(12): 65, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169232

RESUMO

PURPOSE OF REVIEW: Olfactory testing is a potentially safe, cost-effective, bedside evaluation tool for diagnosis, monitoring, and risk assessment for surgery in temporal lobe epilepsy (TLE) patients, but testing methods and relevant olfactory domains are not standardized. We conducted a systematic review to evaluate olfactory tests in TLE and summarize the results of the literature. RECENT FINDINGS: Olfactory tests varied significantly in odorant administration tools and devices, target odorants, evaluation timing, and grading scales. The Smell Threshold Test and University of Pennsylvania Smell Identification Test were the most validated single-domain tests for odor detection and odor identification, respectively. For multi-domain tests, Odor Memory/Discrimination Test and the Sniffin' Sticks test were the most validated. Results of olfactory tests in TLE are presented by domain. Rigorous validation, standardization, and comparative analysis of existing olfactory tests by domain is urgently needed to establish the utility and efficacy of olfactory testing in TLE.


Assuntos
Epilepsia do Lobo Temporal , Transtornos do Olfato , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico , Humanos , Memória , Odorantes , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/etiologia , Olfato
15.
J Clin Neurosci ; 81: 158-160, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33222907

RESUMO

Psychotropic medications have modulatory effects on spinal cord stimulator (SCS) therapy and may play an important role in determining treatment success in chronic pain management. However, it remains unknown how SCS affects psychotropic use and whether the medications affect outcome. We performed a retrospective study to determine the prevalence of psychotropic medication (i.e. anxiolytic, antidepressant, and anticonvulsant) use among new SCS patients immediately before implantation and characterized the dosage changes at 1-year. We also sought to understand whether pre-operative medication status affects outcome, defined as device explantation due to treatment failure. In an analysis of 45 patients, 31%, 51% and 71% were actively taking anxiolytics, antidepressants, and anticonvulsants, respectively, before surgery. In the majority of cases, daily dosages remained the same for all three classes of medication at 1-year. Patients who were on two or more classes of medications pre-operatively had significantly lower explantation rate compared to those with one or none (12% vs. 43%, p = 0.041) and had 5.25 times less likelihood of explanation in the future (OR 5.25, 95%CI 1.18-23.2, p = 0.029). Our study suggest that peri-operative multimodality medical treatment may enhance the therapeutic efficacy and durability of SCS in carefully selected chronic pain patients.


Assuntos
Psicotrópicos/uso terapêutico , Estimulação da Medula Espinal/estatística & dados numéricos , Adulto , Antidepressivos , Dor Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Medula Espinal , Resultado do Tratamento
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3590-3593, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018779

RESUMO

Phase-amplitude coupling (PAC), in which the amplitude of a faster neural oscillation couples to the phase of a slower rhythm, is one of the most common representations of complex neuronal rhythmic activities. In a healthy brain, PAC accompanies cognitive function, and abnormal patterns of PAC have been linked to several neurological disorders. Among the various brain neuromodulation techniques, phase-dependent stimulation has a strong potential to modulate PAC levels. In this study, we utilize a computational model in the NEURON environment based on a detailed mathematical model of neuronal populations, consisting of networks with both excitatory and inhibitory neurons, to simulate PAC generation. The model was then used to investigate the modulatory effects of phase-dependent stimulation on the generated PAC. Simulated data from the model shows that stimulation locked to the phase of slower rhythms increased PAC level during stimulation. These results demonstrate the capacity of phase-dependent stimulation to modulate PAC, which could allow for applications in the treatment of neurological disorders associated with abnormal PAC, such as Parkinson's disease.Clinical Relevance- Analyzing the origins of neuronal PAC and developing a brain stimulation technique for modulating the level of PAC can facilitate the development of novel treatment methods for neurological disorders associated with abnormal cross-frequency coupling.


Assuntos
Neurônios , Doença de Parkinson , Encéfalo , Cognição , Humanos , Doença de Parkinson/terapia
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3658-3661, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018794

RESUMO

Parkinson's Disease (PD) is a neurodegenerative disease characterized by its hallmark motor symptoms of bradykinesia and tremor. Numerous studies have suggested novel quantification methods of its symptoms. However, there lacks the means to accurately assess improvements in an intraoperative setting during deep brain stimulation (DBS) electrode implantation. This study introduces a methodology to quantify selected PD motor symptoms in such a restrictive environment using a wireless Leap Motion sensor. The result suggests that utilizing the Leap Motion sensor intraoperatively is feasible for quantifying motor parameters for bradykinesia and resting tremor of a PD patient.


Assuntos
Estimulação Encefálica Profunda , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Hipocinesia/diagnóstico , Doença de Parkinson/diagnóstico , Tremor/diagnóstico
18.
Epilepsia ; 61(9): 1949-1957, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32944948

RESUMO

OBJECTIVE: Olfactory dysfunction has been well documented in individuals with temporal lobe epilepsy, but its use in presurgical planning has yet to be examined. We assessed the role of preoperative odor identification in mesial onset seizure localization utilizing stereoelectroencephalography (S-EEG) and magnetic resonance-guided laser interstitial thermal therapy (MRgLiTT) outcome. METHODS: We identified 30 patients who had typical seizures captured during S-EEG monitoring or MRgLiTT of mesial temporal structures (n = 17 S-EEG, n = 13 MRgLiTT); seizure onset zone was classified as unilateral mesial seizure onset, or multifocal with unilateral mesial onset and nonmesial onset. Odor identification ability was assessed using the Sniffin' Sticks Odor Identification Test (SSOIT). Patients also completed measures of confrontation naming and auditory-verbal learning/memory using the Boston Naming Test and Hopkins Verbal Learning Test-Revised, respectively. RESULTS: Overall, patients with intractable focal epilepsy exhibited poor olfactory performance (median [M] = 10.4, interquartile range [IQR] = 9.4-11.8). Of 19 patients who underwent MRgLiTT, 10 patients (52.6%) were seizure-free at last follow-up (M = 13 months, IQR =10-18). Patients who were seizure-free after MRgLiTT (n = 10) had poorer odor identification scores (M = 9, IQR = 7-13) compared to patients with seizure reoccurrence (M = 13, IQR = 12.5-15). Odor identification score was inversely associated with seizure freedom, with odds ratio = 0.60 (95% confidence interval [CI] = 0.38-0.95, P = .03). Receiver operating characteristic analysis revealed that an SSOIT score of 12 was the ideal cutoff for predicting favorable seizure outcome (area under the curve = 0.84, 95% CI = 0.64-1.0). Sensitivity was 88.9% and specificity was 78.9%, with a likelihood ratio of 2.9 of seizure failure in patients who had an odor identification score ≥ 12. SIGNIFICANCE: Interictal olfactory dysfunction is commonly seen in patients with intractable focal epilepsy. Odor identification is a novel, noninvasive presurgical biomarker to distinguish who may or may not benefit from MRgLiTT of mesial temporal structures.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Terapia a Laser/métodos , Imageamento por Ressonância Magnética , Procedimentos Neurocirúrgicos/métodos , Transtornos do Olfato/fisiopatologia , Adulto , Epilepsia Resistente a Medicamentos/complicações , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/fisiopatologia , Eletroencefalografia , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Humanos , Testes de Linguagem , Masculino , Testes de Memória e Aprendizagem , Pessoa de Meia-Idade , Transtornos do Olfato/complicações , Prognóstico , Técnicas Estereotáxicas , Cirurgia Assistida por Computador/métodos , Resultado do Tratamento , Aprendizagem Verbal , Adulto Jovem
19.
Epilepsy Behav Rep ; 14: 100366, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32518903

RESUMO

Anterior temporal lobectomy and amygdalohippocampectomy (ATL) is the gold standard surgical treatment for drug resistant mesial temporal lobe epilepsy (mTLE). Nevertheless, seizure recurrence after ATL is not uncommon. Insufficient resection of the mesial temporal structures remains one of the most common reasons for ATL failure. Extending the resection leads to improved seizure outcome in a majority of patients. However, repeat craniotomy can be higher risk for the patient and also can be technically challenging due to scarring and altered anatomy. Laser interstitial thermal therapy (LITT) is a novel minimally invasive alternative to ATL, and it has been shown to be safe and effective. However, it is unclear if LITT has a role in managing post-ATL mTLE patients with recurrent seizures and residual epileptogenic structures. LITT is an attractive option for post-ATL patients with residual mesial structures because the surgery is minimally invasive, and it allows precise targeting and real time confirmation of tissue ablation under MRI guidance. We present a case of an mTLE patient with recurrent seizures after ATL who achieved long-term seizure-freedom after successfully undergoing LITT to ablate the residual hippocampus. This approach, if demonstrated to be safe, effective and durable, can benefit select post-ATL mTLE patients.

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