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BACKGROUND: Current evidence is inconsistent on the benefits of aerobic exercise training for preventing or attenuating age-related cognitive decline in older adults. OBJECTIVE: To investigate the effects of a 1-year progressive, moderate-to-high intensity aerobic exercise intervention on cognitive function, brain volume, and cortical thickness in sedentary but otherwise healthy older adults. METHODS: We randomized 73 older adults to a 1-year aerobic exercise or stretching-and-toning (active control) program. The primary outcome was a cognitive composite score calculated from eight neuropsychological tests encompassing inductive reasoning, long-term and working memory, executive function, and processing speed. Secondary outcomes were brain volume and cortical thickness assessed by MRI, and cardiorespiratory fitness measured by peak oxygen uptake (VO2 ). RESULTS: One-year aerobic exercise increased peak VO2 by â¼10% (p < 0.001) while it did not change with stretching (p = 0.241). Cognitive composite scores increased in both the aerobic and stretching groups (p < 0.001 for time effect), although no group difference was observed. Total brain volume (p < 0.001) and mean cortical thickness (p = 0.001) decreased in both groups over time, while the reduction in hippocampal volume was smaller in the stretching group compared with the aerobic group (p = 0.040 for interaction). Across all participants, improvement in peak VO2 was positively correlated with increases in cognitive composite score (r = 0.282, p = 0.042) and regional cortical thickness at the inferior parietal lobe (p = 0.016). CONCLUSIONS: One-year aerobic exercise and stretching interventions improved cognitive performance but did not prevent age-related brain volume loss in sedentary healthy older adults. Cardiorespiratory fitness gain was positively correlated with cognitive performance and regional cortical thickness.
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Disfunção Cognitiva , Exercício Físico , Idoso , Cognição , Disfunção Cognitiva/psicologia , Terapia por Exercício , Humanos , Testes Neuropsicológicos , OxigênioRESUMO
This manuscript introduces the latest generation of a patient-mounted platform designed for segmental injections of therapeutics direct into the spinal cord parenchyma. It emphasizes its importance and it presents the rationale for developing this delivery methodology. It compares the newest with the previous generations, detailing how the modifications can streamline transportation, assembly, sterilization, and utilization of the platform by different surgeons. Finally, the illustrations depict the main alterations, as well as a cadaveric assessment of the device prototype in the cervical and thoracolumbar regions.
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Medula Espinal , Humanos , Injeções Espinhais , Medula Espinal/cirurgiaRESUMO
BACKGROUND: The aim of this project was to analyse whether a CT influences surgical planning in ankle fracture involving the posterior malleolus. METHODS: Twenty consecutive patients with fractures involving the posterior malleolus were retrospectively selected and had their plain radiographs and CT scan anonymised. Initially, radiographs alone were presented to nine trauma surgeons to formulate a surgical plan individually. After a minimum of 6 weeks, the same process was repeated with CT scans available. RESULTS: The surgical approach for ankle fracture fixation changed in 32.7% of cases following CT scan review. A CT scan altered the decision to stabilise the posterior malleolus in 25.6% and the decision of whether to stabilise the syndesmosis in 16.6% of cases. CONCLUSIONS: This study demonstrates that a pre-operative CT scan changes the surgical approach in 32.7% of cases and therefore we recommend use of CT scanning in this subset of ankle injuries.
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Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Tomada de Decisão Clínica , Cuidados Pré-Operatórios , Cirurgiões , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Fraturas do Tornozelo/classificação , Feminino , Fixação de Fratura , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Radiografia , Estudos Retrospectivos , Adulto JovemRESUMO
Study Design: Observational study using insurance claims. Objective: To quantify opioid usage leading up to spinal cord stimulation (SCS) and the potential impact on outcomes of SCS. Setting: SCS is an interventional therapy that often follows opioid usage in the care continuum for chronic pain. Methods: This study identified SCS patients using the Truven Health MarketScan databases from January 2010 to December 2014. The index event was the first occurrence of a permanent SCS implant. Indicators of opioid usage at implant were daily morphine equivalent dose (MED), number of unique pain drug classes, and diagnosis code for opioid abuse. System explant was used as a measure of ineffective SCS therapy. Multivariate logistic regression was used to analyze the effect of pre-implant medications on explants. Results: A total of 5,476 patients (56 ± 14 years; 60% female) were included. SCS system removal occurred in 390 patients (7.1%) in the year after implant. Number of drug classes (odds ratio [OR] = 1.11, P = 0.007) and MED level (5-90 vs < 5 mg/d: OR = 1.32, P = 0.043; ≥90 vs < 5 mg/d: OR = 1.57, P = 0.005) were independently predictive of system explant. Over the year before implant, MED increased in 54% (stayed the same in 21%, decreased in 25%) of patients who continued with SCS and increased in 53% (stayed the same in 20%, decreased in 27%) of explant patients (P = 0.772). Over the year after implant, significantly more patients with continued SCS had an MED decrease (47%) or stayed the same (23%) than before (P < 0.001). Conclusions: Chronic pain patients receive escalating opioid dosage prior to SCS implant, and high-dose opioid usage is associated with an increased risk of explant. Neuromodulation can stabilize or decrease opioid usage. Earlier consideration of SCS before escalated opioid usage has the potential to improve outcomes in complex chronic pain.
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Analgésicos Opioides/uso terapêutico , Dor Crônica/terapia , Estimulação da Medula Espinal , Resultado do Tratamento , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Brain changes in response to nerve damage or cochlear trauma can generate pathological neural activity that is believed to be responsible for many types of chronic pain and tinnitus. Several studies have reported that the severity of chronic pain and tinnitus is correlated with the degree of map reorganization in somatosensory and auditory cortex, respectively. Direct electrical or transcranial magnetic stimulation of sensory cortex can temporarily disrupt these phantom sensations. However, there is as yet no direct evidence for a causal role of plasticity in the generation of pain or tinnitus. Here we report evidence that reversing the brain changes responsible can eliminate the perceptual impairment in an animal model of noise-induced tinnitus. Exposure to intense noise degrades the frequency tuning of auditory cortex neurons and increases cortical synchronization. Repeatedly pairing tones with brief pulses of vagus nerve stimulation completely eliminated the physiological and behavioural correlates of tinnitus in noise-exposed rats. These improvements persisted for weeks after the end of therapy. This method for restoring neural activity to normal may be applicable to a variety of neurological disorders.
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Plasticidade Neuronal/fisiologia , Zumbido/fisiopatologia , Zumbido/terapia , Estimulação Acústica , Animais , Percepção Auditiva/fisiologia , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Estimulação Elétrica , Feminino , Modelos Neurológicos , Ruído/efeitos adversos , Ratos , Ratos Sprague-Dawley , Zumbido/etiologia , Zumbido/patologia , Nervo Vago/fisiologiaRESUMO
Surgical intervention is of proven benefit in an appropriately selected subset of patients with medically refractory temporal lobe epilepsy. In these patients, a surgical cure both provides the quality of life improvement that comes from seizure freedom as well as a survival benefit. However, patients who undergo open surgical intervention may have a worsening in neurobehavioral outcomes. Laser interstitial thermal therapy (LITT) represents a minimally invasive surgical intervention that has shown promise in improving post-operative neurobehavioral outcomes. Further, the minimally invasive nature of this procedure holds the possibility to shift the significant under-penetration of surgical intervention that exists for eligible medically refractory patients. Herein, we review open surgical resection-based techniques and the clinical data to date for LITT.
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Encéfalo/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Procedimentos Neurocirúrgicos , Convulsões/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Procedimentos Neurocirúrgicos/métodos , Convulsões/diagnóstico , Resultado do TratamentoRESUMO
Cerebral hypoperfusion elevates the risk of brain white matter (WM) lesions and cognitive impairment. Central artery stiffness impairs baroreflex, which controls systemic arterial perfusion, and may deteriorate neuronal fiber integrity of brain WM. The purpose of this study was to examine the associations among brain WM neuronal fiber integrity, baroreflex sensitivity (BRS), and central artery stiffness in older adults. Fifty-four adults (65 ± 6 years) with normal cognitive function or mild cognitive impairment (MCI) were tested. The neuronal fiber integrity of brain WM was assessed from diffusion metrics acquired by diffusion tensor imaging. BRS was measured in response to acute changes in blood pressure induced by bolus injections of vasoactive drugs. Central artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). The WM diffusion metrics including fractional anisotropy (FA) and radial (RD) and axial (AD) diffusivities, BRS, and cfPWV were not different between the control and MCI groups. Thus, the data from both groups were combined for subsequent analyses. Across WM, fiber tracts with decreased FA and increased RD were associated with lower BRS and higher cfPWV, with many of the areas presenting spatial overlap. In particular, the BRS assessed during hypotension was strongly correlated with FA and RD when compared with hypertension. Executive function performance was associated with FA and RD in the areas that correlated with cfPWV and BRS. These findings suggest that baroreflex-mediated control of systemic arterial perfusion, especially during hypotension, may play a crucial role in maintaining neuronal fiber integrity of brain WM in older adults.
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Barorreflexo/fisiologia , Artérias Cerebrais/fisiologia , Fibras Nervosas Mielinizadas/fisiologia , Rigidez Vascular/fisiologia , Substância Branca/fisiologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/anatomia & histologia , Imagem de Tensor de Difusão , Feminino , Hemodinâmica , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Substância Branca/citologiaRESUMO
PURPOSE OF REVIEW: New minimally invasive techniques are becoming available to treat focal-onset epilepsy. The open surgical treatment of mesial temporal lobe epilepsy (MTLE), although associated with high rates of seizure freedom, is confounded by adverse impacts on neurocognitive function. This review covers new techniques being explored for surgical treatment of MTLE that in early studies have been achieving high seizure-free rates with preservation of memory and other functions referable to the mesial and lateral temporal regions. RECENT FINDINGS: Multiple subpial transections of the hippocampus, and stereotactic approaches including radiofrequency ablation and laser interstitial thermal therapy have achieved rates of seizure freedom comparable to open resection but with fewer neurocognitive adverse effects. Electrical neuromodulation approaches, including responsive neurostimulation, direct hippocampal stimulation, and thalamic deep brain stimulation preserve cognitive function and achieve significant seizure suppression, but have not yet achieved high seizure-free rates. SUMMARY: With the recent success in minimally invasive approaches with respect to seizure freedom and preservation of neurocognitive functions, it is predicted that fewer patients will be receiving 'classic' open resections for MTLE such as temporal lobectomy. These new approaches also promise to decrease discomfort, time away from work, and healthcare utilization.
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Cognição/fisiologia , Epilepsia do Lobo Temporal/cirurgia , Memória/fisiologia , Lobo Temporal/cirurgia , Animais , Epilepsia do Lobo Temporal/diagnóstico , Humanos , Procedimentos Neurocirúrgicos/métodos , Lobo Temporal/fisiopatologia , Resultado do TratamentoRESUMO
BACKGROUND: IL-4 and signal transducer and activator of transcription 6 (STAT6) play an important role in the progression of allergic airway disease (AAD) or asthma. IL-4 and STAT6 mediate T(H)2 responses in T cells and immunoglobulin class-switching to IgE in B cells. Both T(H)2 responses and IgE promote the asthmatic condition. We have previously demonstrated that poly (ADP-ribose) polymerase (PARP) 14, a member of the PARP family of proteins, regulates the transcription function of STAT6. However, the role of PARP-14 in AAD is not known. OBJECTIVE: Here we investigate the role of PARP-14 and the enzyme activity associated with it in a model of AAD dependent on airway hyperresponsiveness and lung inflammation. We also elucidate the mechanism by which PARP-14 regulates AAD. METHODS: The role of PARP-14 and its enzyme activity in AAD and T(H)2 differentiation were examined by using a murine model of AAD and in vitro T(H) cell differentiation. RESULTS: PARP-14-deficient animals show reduced lung pathology and IgE levels when compared with control animals. Treating mice with a pharmacologic inhibitor for PARP activity reduced the severity of airway hyperresponsiveness and lung inflammation. Mechanistically, our data indicate that PARP-14 and its enzyme activity aid in the differentiation of T cells toward a T(H)2 phenotype by regulating the binding of STAT6 to the Gata3 promoter. CONCLUSION: PARP-14 and the catalytic activity associated with it promote T(H)2 differentiation and AAD in a murine model, and targeting PARP-14 might be a potential new therapy for allergic asthma.
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Hiper-Reatividade Brônquica/patologia , Hipersensibilidade/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Doenças Respiratórias/patologia , Células Th2/enzimologia , Células Th2/patologia , Animais , Asma/genética , Asma/metabolismo , Asma/patologia , Hiper-Reatividade Brônquica/enzimologia , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/metabolismo , Diferenciação Celular/imunologia , Células Cultivadas , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Hipersensibilidade/genética , Hipersensibilidade/metabolismo , Imunoglobulina E/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/imunologia , Regiões Promotoras Genéticas/genética , Doenças Respiratórias/enzimologia , Doenças Respiratórias/genética , Doenças Respiratórias/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , Células Th2/metabolismoRESUMO
Hearing loss can lead to long-lasting effects on the central nervous system, and current therapies, such as auditory training and rehabilitation, show mixed success in improving perception and speech comprehension. Vagus nerve stimulation (VNS) is an adjunctive therapy that can be paired with rehabilitation to facilitate behavioral recovery after neural injury. However, VNS for auditory recovery has not been tested after severe hearing loss or significant damage to peripheral receptors. This study investigated the utility of pairing VNS with passive or active auditory rehabilitation in a rat model of noise-induced hearing loss. Although auditory rehabilitation helped rats improve their frequency discrimination, learn novel speech discrimination tasks, and achieve speech-in-noise performance similar to normal hearing controls, VNS did not enhance recovery of speech sound perception. These results highlight the limitations of VNS as an adjunctive therapy for hearing loss rehabilitation and suggest that optimal benefits from neuromodulation may require restored peripheral signaling.
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Learning new skills requires neuroplasticity. Vagus nerve stimulation (VNS) during sensory and motor events can increase neuroplasticity in networks related to these events and might therefore serve to facilitate learning on sensory and motor tasks. We tested if VNS could broadly improve learning on a wide variety of tasks across different skill domains in healthy, female adult rats. VNS was paired with presentation of stimuli or on successful trials during training, strategies known to facilitate plasticity and improve recovery in models of neurological disorders. VNS failed to improve either rate of learning or performance for any of the tested tasks, which included skilled forelimb motor control, speech sound discrimination, and paired-associates learning. These results contrast recent findings from multiple labs which found VNS pairing during training produced learning enhancements across motor, auditory, and cognitive domains. We speculate that these contrasting results may be explained by key differences in task designs, training timelines and animal handling approaches, and that while VNS may be able to facilitate rapid and early learning processes in healthy subjects, it does not broadly enhance learning for difficult tasks.
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Aprendizagem , Estimulação do Nervo Vago , Animais , Estimulação do Nervo Vago/métodos , Ratos , Feminino , Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Ratos Sprague-Dawley , Destreza Motora/fisiologiaRESUMO
OBJECTIVES: The aim of this study was to report experience of a major trauma center utilizing circular frames as definitive fixation in patients sustaining Gustilo-Anderson 3B open tibial fractures. DESIGN: A prospectively maintained database was retrospectively interrogated. SETTING: Single major trauma center in the United Kingdom. PATIENT SELECTION CRITERIA: All patients over the age of 16 sustaining an open tibial fracture with initial debridement performed at the study center. All patients also received orthoplastic care for a soft tissue defect (via skeletal deformation or a soft tissue cover procedure) and subsequent definitive management using an Ilizarov ring fixator. Patients who received primary debridement at another center, had preexisting infection, sustained a periarticular fracture, or those who did not afford a minimum of 12-month follow-up were excluded. Case notes and radiographs were reviewed to collate patient demographics and injury factors. OUTCOME MEASURES AND COMPARISONS: The primary outcome of interest was deep infection rate with secondary outcomes including time to union and secondary interventions. RESULTS: Two hundred twenty-five patients met inclusion criteria. Mean age was 43.2 year old, with 72% males, 34% smokers, and 3% diabetics. Total duration of frame management averaged 6.4 months (SD 7.7). Eight (3.5%) patients developed a deep infection and 41 (20%) exhibited signs of a pin site infection. Seventy-nine (35.1%) patients had a secondary intervention, of which 8 comprised debridement of deep infection, 29 bony procedures, 8 soft tissue operations, 30 frame adjustments, and 4 patients requiring a combination of soft tissue and bony procedures. Bony union was achieved in 221 cases (98.2%), 195 (86.7%) achieved union in a single frame without the need for secondary intervention, 26 required frame adjustments to achieve union. Autologous bone grafts were used in 10 cases. CONCLUSIONS: Orthoplastic care including circular frame fixation for Gustilo-Anderson-3B fractures of the tibia resulted in a low rate of deep infection (3.5%) and achieved excellent union rates (98.2%). LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
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Fraturas Expostas , Fraturas da Tíbia , Centros de Traumatologia , Humanos , Fraturas da Tíbia/cirurgia , Masculino , Fraturas Expostas/cirurgia , Feminino , Adulto , Resultado do Tratamento , Pessoa de Meia-Idade , Fixadores Externos , Reino Unido , Estudos Prospectivos , Adulto Jovem , Estudos Retrospectivos , Bases de Dados Factuais , Desbridamento , Adolescente , Consolidação da Fratura , Fixação de Fratura/métodos , Infecção da Ferida Cirúrgica/epidemiologiaRESUMO
The impact of aerobic exercise training (AET) on cerebral blood flow (CBF) regulation remains inconclusive. This study investigated the effects of one-year progressive, moderate-to-vigorous AET on CBF, central arterial stiffness, and cognitive performance in cognitively normal older adults. Seventy-three older adults were randomly assigned to AET or stretching-and-toning (SAT, active control) intervention. CBF was measured with 2D duplex ultrasonography. Central arterial stiffness, measured by carotid ß-stiffness index, was assessed with the ultrasonography and applanation tonometry. Cerebrovascular resistance (CVR) was calculated as mean arterial pressure divided by CBF. A cognitive battery was administered with a focus on memory and executive function. Cardiorespiratory fitness was measured by peak oxygen consumption (VËO2peak). One-year AET increased VËO2peak and CBF and decreased CVR and carotid ß-stiffness index. In the AET group, improved VËO2peak was correlated with increased CBF (r = 0.621, p = 0.001) and decreased CVR (r = -0.412, p = 0.037) and carotid ß-stiffness index (r = -0.478, p = 0.011). Further, increased Woodcock-Johnson recall score was associated with decreased CVR (r = -0.483, p = 0.012) and carotid ß-stiffness index (r = -0.498, p = 0.008) in AET group (not in SAT group). In conclusion, one-year progressive, moderate-to-vigorous aerobic exercise training increased CBF and decreased carotid arterial stiffness and CVR which were associated with improved memory function in cognitively normal older adults.
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Aptidão Cardiorrespiratória , Exercício Físico , Rigidez Vascular , Pressão Arterial , Artérias Carótidas/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Exercício Físico/fisiologia , Rigidez Vascular/fisiologia , Humanos , AdultoRESUMO
Introduction: Repeatedly pairing a tone with vagus nerve stimulation (VNS) alters frequency tuning across the auditory pathway. Pairing VNS with speech sounds selectively enhances the primary auditory cortex response to the paired sounds. It is not yet known how altering the speech sounds paired with VNS alters responses. In this study, we test the hypothesis that the sounds that are presented and paired with VNS will influence the neural plasticity observed following VNS-sound pairing. Methods: To explore the relationship between acoustic experience and neural plasticity, responses were recorded from primary auditory cortex (A1) after VNS was repeatedly paired with the speech sounds 'rad' and 'lad' or paired with only the speech sound 'rad' while 'lad' was an unpaired background sound. Results: Pairing both sounds with VNS increased the response strength and neural discriminability of the paired sounds in the primary auditory cortex. Surprisingly, pairing only 'rad' with VNS did not alter A1 responses. Discussion: These results suggest that the specific acoustic contrasts associated with VNS can powerfully shape neural activity in the auditory pathway. Methods to promote plasticity in the central auditory system represent a new therapeutic avenue to treat auditory processing disorders. Understanding how different sound contrasts and neural activity patterns shape plasticity could have important clinical implications.
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A subset of poly ADP-ribose polymerases (PARP) that also contain macro domains regulate transcription. One such macro PARP, PARP-14 alters interleukin 4 (IL-4) and Stat6-dependent transcription. Stat6, activated by IL-4 plays an important role in T helper cell immunity and B cell responses. Here we define the mechanism by which PARP-14 regulates Stat6-activated transcription. Under non-stimulating conditions, PARP-14 recruits HDAC 2 and 3 to IL-4 responsive promoters. In the presence of IL-4, PARP-14 promotes efficient binding of Stat6 to its target genes. Moreover, HDAC 2 and 3 are released from the promoter with an IL-4 signal, this is aided by the ADP-ribosylation of the HDACs by PARP-14. The HDACs and PARP-14 get replaced by coactivators containing HAT activity. Based on these observations we put forth a mechanism in which PARP-14 functions as a transcriptional switch for Stat6-dependent gene induction. Thus, in the absence of a signal PARP-14 acts as a transcriptional repressor by recruiting HDACs. In contrast, in the presence of IL-4 the catalytic activity of PARP-14 facilitates Stat6 binding to the promoter, and release of HDACs so as to activate transcription.
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Poli(ADP-Ribose) Polimerases/metabolismo , Regiões Promotoras Genéticas/fisiologia , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT6/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Transcrição Gênica/fisiologia , Animais , Linhagem Celular , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Camundongos , Camundongos Knockout , Poli(ADP-Ribose) Polimerases/genética , Proteínas Repressoras/genética , Fator de Transcrição STAT6/genética , Linfócitos T Auxiliares-Indutores/citologiaRESUMO
Intense noise exposure is a leading cause of hearing loss, which results in degraded speech sound discrimination ability, particularly in noisy environments. The development of an animal model of speech discrimination deficits due to noise induced hearing loss (NIHL) would enable testing of potential therapies to improve speech sound processing. Rats can accurately detect and discriminate human speech sounds in the presence of quiet and background noise. Further, it is known that profound hearing loss results in functional deafness in rats. In this study, we generated rats with a range of impairments which model the large range of hearing impairments observed in patients with NIHL. One month after noise exposure, we stratified rats into three distinct deficit groups based on their auditory brainstem response (ABR) thresholds. These groups exhibited markedly different behavioral outcomes across a range of tasks. Rats with moderate hearing loss (30 dB shifts in ABR threshold) were not impaired in speech sound detection or discrimination. Rats with severe hearing loss (55 dB shifts) were impaired at discriminating speech sounds in the presence of background noise. Rats with profound hearing loss (70 dB shifts) were unable to detect and discriminate speech sounds above chance level performance. Across groups, ABR threshold accurately predicted behavioral performance on all tasks. This model of long-term impaired speech discrimination in noise, demonstrated by the severe group, mimics the most common clinical presentation of NIHL and represents a useful tool for developing and improving interventions to target restoration of hearing.
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Perda Auditiva Provocada por Ruído , Percepção da Fala , Animais , Limiar Auditivo , Potenciais Evocados Auditivos do Tronco Encefálico , Audição , Humanos , Ruído/efeitos adversos , RatosRESUMO
BACKGROUND: COVID-19 has had a significant impact on the economy, health care, and society as a whole. To prevent the spread of infection, local governments across the United States issued mandatory lockdowns and stay-at-home orders. In the surgical world, elective cases ceased to help "flatten the curve" and prevent the infection from spreading to hospital staff and patients. We explored the effect of the cancellation of these procedures on trainee operative experience at our high-volume, multihospital neurosurgical practice. METHODS: Our department cancelled all elective cases starting March 16, 2020, and resumed elective surgical and endovascular procedures on May 11, 2020. We retrospectively reviewed case volumes for 54 days prelockdown and 54 days postlockdown to evaluate the extent of the decrease in surgical volume at our institution. Procedure data were collected and then divided into cranial, spine, functional, peripheral nerve, pediatrics, and endovascular categories. RESULTS: Mean total cases per day in the prelockdown group were 12.26 ± 7.7, whereas in the postlockdown group, this dropped to 7.78 ± 5.5 (P = 0.01). In the spine category, mean cases per day in the prelockdown group were 3.13 ± 2.63; in the postlockdown group, this dropped to 0.96 ± 1.36 (P < 0.001). In the functional category, mean cases per day in the prelockdown group were 1.31 ± 1.51, whereas in the postlockdown group, this dropped to 0.11 ± 0.42 (P < 0.001). For cranial (P = 0.245), peripheral nerve (P = 0.16), pediatrics (P = 0.34), and endovascular (P = 0.48) cases, the volumes dropped but were not statistically significant decreases. CONCLUSION: The impact of this outbreak on operative training does appear to be significant based solely on statistics. Although the drop in case volumes during this time can be accounted for by the pandemic, it is important to understand that this is a multifactorial effect. Further studies are needed for these results to be generalizable and to fully understand the effect this pandemic has had on trainee operative experience.
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Deep brain stimulation is the most advanced and effective neuromodulation therapy for Parkinson disease, essential tremor, and generalized dystonia. This article discusses how imaging improves surgical techniques and outcomes and widens possibilities in translational neuroscience in Parkinson disease, essential tremor, generalized dystonia, and epilepsy. In movement disorders diffusion tensor imaging allows anatomic segment of cortical areas and different functional subregions within deep-seated targets to understand the side effects of stimulation and gain more data to describe the therapeutic mechanism of action. The introduction of visualization of white matter tracks increases the safety of neurosurgical techniques in functional neurosurgery and neuro-oncology.
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Estimulação Encefálica Profunda/métodos , Transtornos dos Movimentos/diagnóstico por imagem , Transtornos dos Movimentos/terapia , Neuroimagem/métodos , Técnicas Estereotáxicas , Imagem de Tensor de Difusão/métodos , Distonia/diagnóstico por imagem , Distonia/terapia , Epilepsia/diagnóstico por imagem , Epilepsia/terapia , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/terapia , Humanos , Procedimentos Neurocirúrgicos/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapiaRESUMO
Age is the strongest risk factor for cerebrovascular disease; however, age-related changes in cerebrovascular function are still not well understood. The objective of this study was to measure cerebral vasomotor reactivity (CVMR) during hypo- and hypercapnia across the adult lifespan. One hundred fifty-three healthy participants (21-80 years) underwent measurements of cerebral blood flow velocity (CBFV) via transcranial Doppler, mean arterial pressure (MAP) via plethysmograph, and end-tidal CO2 (EtCO2) via capnography during hyperventilation (hypocapnia) and a modified rebreathing protocol (hypercapnia). Cerebrovascular conductance (CVCi) and resistance (CVRi) indices were calculated from the ratios of CBFV and MAP. CVMRs were assessed by the slopes of CBFV and CVCi in response to changes in EtCO2. The baseline CBFV and CVCi decreased and CVRi increased with age. Advanced age was associated with progressive declines in CVMR during hypocapnia indicating reduced cerebral vasoconstriction, but increases in CVMR during hypercapnia indicating increased vasodilation. A negative correlation between hypo- and hypercapnic CVMRs was observed across all subjects (CBFV%/ EtCO2: r = -0.419, CVCi%/ EtCO2: r = -0.442, P < 0.0001). Collectively, these findings suggest that aging is associated with decreases in CBFV, increases in cerebrovascular resistance, reduced vasoconstriction during hypocapnia, but increased vasodilatory responsiveness during hypercapnia.
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Envelhecimento , Pressão Sanguínea , Circulação Cerebrovascular , Hipercapnia , Hipocapnia , Ultrassonografia Doppler Transcraniana , Resistência Vascular , Vasoconstrição , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipercapnia/diagnóstico por imagem , Hipercapnia/fisiopatologia , Hipocapnia/diagnóstico por imagem , Hipocapnia/fisiopatologia , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) or globus pallidus internus (GPi) is the surgical method of choice to treat the canonical symptoms of Parkinson disease, occasionally surgical sites become infected or the hardware erodes, necessitating explantation. Usual practice is to remove and reimplant replacement leads after tissue healing, leaving patients without the clinical benefits of DBS for several months, and at risk for DBS withdrawal in some, and some patients are no longer good surgical candidates for reimplantation. Radiofrequency ablation through the DBS lead is an option for these patients. METHODS: We performed a retrospective chart review of all patients who underwent radiofrequency ablation of the STN or GPi through indwelling DBS leads performed before hardware removal at our institution. We generated patient-specific anatomic models to determine lesion locations and volumes. RESULTS: Six patients underwent radiofrequency ablation of the STN (n = 4) and GPi (n = 2) through indwelling DBS leads. All 6 of these patients initially showed comparable motor symptom relief to that experienced with DBS before lesioning, with 4 patients sustaining meaningful long-term (≥2 years) improvement. Better outcomes were achieved in those patients with a higher percentage of the planned target lesioned. CONCLUSIONS: Radiofrequency ablation through indwelling DBS leads before explantation could be considered a viable alternative to subsequent reimplantation or stereotactic lesion in patients with Parkinson disease in whom hardware explantation is necessary, if the patient achieved substantive symptom relief with DBS. This approach avoids symptom exacerbation while awaiting revision surgery.