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We investigated the electrophysiological relationships in the cortico-basal ganglia network on a sub-centimeter scale to increase our understanding of neural functional relationships in Parkinson's disease (PD).Data was intraoperatively recorded from 2 sources in the human brain-a microelectrode in the subthalamic nucleus (STN) and a micro-electrocorticography grid on the motor association cortex-during bilateral deep brain stimulation (DBS) electrode placement. STN neurons and local field potential (LFP) were defined as functionally connected when the 99.7% confidence intervals of the action potential (AP)-aligned average LFP and control did not overlap.APs from STN neurons were functionally connected to the STN LFP for 18/46 STN neurons. This functional connection was observed between STN neuron APs and cortical LFP for 25/46 STN neurons. The cortical patterns of electrophysiological functional connectivity differed for each neuron.A subset of single neurons in the STN exhibited functional connectivity with electrophysiological activity in the STN and at a distance with the motor association cortex surveyed on a sub-centimeter spatial scale. These connections show a per neuron differential topography on the cortex.The cortico-basal ganglia circuit is organized on a sub-centimeter scale, and plays an important role in the mechanisms of PD and DBS.

Introducción. Las energías renovables pretenden ser el camino a la descontaminación del planeta, muchas han sido las décadas de contaminación a la que se ha expuesto la tierra, uno de los grandes problemas es la gran dependencia a los combustibles fósiles, esto ha ocasionado grandes espacios del planeta contaminados, enfermedades a los seres humanos, extinción de especies y muchas otras consecuencias graves que aún falta por ver. Objetivo. La presente investigación pretende realizar una exposición de los posibles escenarios en cuanto al planteamiento del uso del aire como materia para generar recursos energéticos al Ecuador. Metodología. Por medio de una investigación del tipo bibliográfica documental, en la cual se revisan las diferentes fuentes de información al respecto como publicaciones científicas, tesis de grado, u otras que contribuyan a la construcción de la investigación. Resultados. Como resultados se destaca el hecho de que el Ecuador posee todas las características para poder realizar una transición al uso de energías renovables como la eólica, que incluso ya se cuenta con este tipo de proyectos; sin embargo, los altos costos y la falta de visión han mermado la capacidad y apuesta por un cambio amigable con el medio ambiente, por otro lado, se hace notoria el impacto positivo que tendría para las comunidades rurales que se cuente con este tipo de energías. Conclusión. Las características geográficas en las que se encuentra al país, en el cual se presenta una calma ecuatorial, no permite que en todos los espacios geográficos del país pueda aprovecharse la energía eólica. Esto no quiere decir que no sea posible, solo que se deben ubicar espacios en donde se pueda aprovechar al máximo el potencial eólico y de esta manera impactar positivamente a dichas zonas rurales.

OBJECTIVES To determine change in restless legs syndrome (RLS) symptoms in essential tremor (ET) patients undergoing bilateral thalamic ventral intermedius (VIM) deep brain stimulation (DBS) surgery. MATERIALS AND METHODS We retrospectively reviewed our database of ET patients with RLS who had undergone VIM DBS for tremor from 2012 to 2020. We reviewed the patients with available International Restless Leg Syndrome Study Group RLS scale scores before and after DBS. Percentage of responders, defined as proportion of patients experiencing three or more point improvement of RLS scores post-DBS, was calculated. We performed two-tailed t-test of pre-DBS and post-DBS RLS scores. RESULTS We identified 13 patients with ET and RLS who had undergone bilateral VIM DBS, of whom nine (69%) were responders post-DBS. Five of 13 patients (38%) had complete resolution of RLS post-DBS. For all patients, mean pre-DBS RLS score was 15.8 ± 7.9 which improved by 46% post-DBS to a mean of 8.5 ± 8.8 (p = 0.007). Four patients rated their RLS scale one night with the stimulator OFF and another night with the stimulator ON. The mean RLS score with stimulator ON was 15.5 ± 7.6 which improved by 53% to a mean of 6.25 ± 7.8 (p = 0.008), with two having complete resolution of RLS with stimulator ON. Of the nine responders, six preferred to keep their stimulator ON at night due to relief of RLS and better subjective quality of sleep. CONCLUSIONS We report for the first time improvement of RLS in patients with ET after bilateral thalamic DBS. Although many ET patients with nonrechargeable DBS systems switch off their stimulator at night to conserve battery life, those with RLS may potentially benefit from keeping their stimulator ON at night to relieve their RLS.

Este libro presenta el diseño de vivienda de interés social realizado en la comuna Joa, su análisis está basado en el presupuesto mínimo para la construcción de una vivienda social. Dentro de la ingeniería y la arquitectura no solo se enfoca en la construcción de viviendas con grandes costos, sino que busca solucionar los problemas de vivienda para personas de bajos recursos económicos logrando brindarle espacios adecuados y funcionales a la familia, y además cuidando al medio ambiente. Para el diseño de esta vivienda se utilizó las normas sismo-resistentes. Tenemos en cuenta que para la construcción se utilizó métodos con bases fundamentales estas provienen de las normas para todo tipo de edificaciones, dentro del uso de los materiales alternativos nos dicen que es el método más antiguo y adecuado para las familias de escasos recursos económicos. Dentro de estos materiales implementamos plancha de EMMEDUE (espuma de polietileno con mallas metálica), teniendo un acabado de mortero para brindar una mejor culminación y fachada, en ella utilizamos perfiles para la implementación del techo con hojas de zinc. El factor fundamental del diseño de la vivienda es mejorar la calidad de vida de muchos familiares de bajos recursos en la comuna Joa del Cantón Jipijapa, provincia Manabí.

Deep brain stimulation (DBS) to the fornix is an investigational treatment option for patients with mild Alzheimer’s Disease. Outcomes from randomized clinical trials have shown that cognitive function improved in some patients but deteriorated in others. One reason could be variance in electrode placement leading to differential engagement of neural circuits. To investigate this, we analyzed a multi-center cohort of 46 patients with DBS to the fornix. Using normative structural and functional connectivity data, we demonstrate that stimulation of the circuit of Papez and stria terminalis robustly associated with cognitive improvement (R = 0.45, p = 0.031). On a local level, the optimal stimulation site resided at the direct interface between these structures (R = 0.33, p = 0.016). Finally, modulating specific distributed brain networks related to memory accounted for optimal outcomes (R = 0.38, p = 0.006). Findings were robust to multiple cross-validation designs and may now define an optimal network target which could subsequently guide refinement of DBS surgery and programming.

OBJECTIVE Electrophysiologic mapping (EM) has been instrumental in advancing neuroscience and ensuring accurate lead placement for deep brain stimulation. However, EM is associated with increased operative time, expense, and potential risk. Intraoperative imaging to verify lead placement provides an opportunity to reassess the clinical role of EM. We investigated whether EM 1) provides new information that corrects suboptimal preoperative target selection by the physician or 2) simply corrects intraoperative stereotactic error, which can instead be quickly corrected with intraoperative imaging. METHODS Deep brain stimulation lead location errors were evaluated by measuring whether repositioning leads based on EM directed the final lead placement 1) away from or 2) toward the original target. We retrospectively identified 50 patients with 61 leads that required repositioning directed by EM. The stereotactic coordinates of each lead were determined with intraoperative computed tomography. RESULTS In 45 of 61 leads (74%), the electrophysiologically directed repositioning moved the lead toward the initial target. The mean radial errors between the preoperative plan and targeted contact coordinates before and after repositioning were 2.2 and 1.5 mm, respectively (P < 0.001). Microelectrode recording was more likely than test stimulation to direct leads toward the initial target (88% vs. 63%; P = 0.03). The nucleus targeted was associated with the likelihood of moving toward the initial target. CONCLUSIONS Electrophysiologic mapping corrected primarily for errors in lead placement rather than providing new information regarding errors in target selection. Thus, intraoperative imaging and improvements in stereotactic techniques may reduce or even eliminate dependence on EM.

The movement towards evidence-based medicine has been highly successful (Fregni, 2019). Clinicians understand the need to practice based on solid and unbiased evidence. However, the pathway towards full use of evidence-based medicine (EBM) has not been completed. There is still a long way to go. One of the main obstacles to the better use of EBM in clinical practice is the lack of research methodology training. It is clear that there is not enough time in the curriculum of medical students to cover the complex field of research methodology (Fregni, 2019). Also, the current methods of teaching have been far from optimal, and therefore, students usually tend to dislike statistics and epidemiology early on, which provides them fewer tools to use EBM in their clinical profession effectively. In this editorial, we convened a group of clinicians and educators (from the Teaching, Learning and Innovation Initiative) from several countries to briefly discuss some of the main challenges we see in medical students' current education that applies to EBM teaching.

Abstarct Because of its involvement in a wide variety of cardiovascular, metabolic and behavioural functions, the hypothalamus constitutes a potential target for neuromodulation in a number of treatment-refractory conditions. The precise neural substrates and circuitry subserving these responses, however, are poorly characterized to date. We sought to retrospectively explore the acute sequelae of hypothalamic region deep brain stimulation and characterize their neuroanatomical correlates. To this end we studied—at multiple international centres—58 patients (mean age: 68.5 ± 7.9 years, 26 females) suffering from mild Alzheimer’s disease who underwent stimulation of the fornix region between 2007 and 2019. We catalogued the diverse spectrum of acutely induced clinical responses during electrical stimulation and interrogated their neural substrates using volume of tissue activated modelling, voxel-wise mapping, and supervised machine learning techniques. In total 627 acute clinical responses to stimulation—including tachycardia, hypertension, flushing, sweating, warmth, coldness, nausea, phosphenes, and fear—were recorded and catalogued across patients using standard descriptive methods. The most common manifestations during hypothalamic region stimulation were tachycardia (30.9%) and warmth (24.6%) followed by flushing (9.1%) and hypertension (6.9%). Voxel-wise mapping identified distinct, locally separable clusters for all sequelae that could be mapped to specific hypothalamic and extrahypothalamic grey and white matter structures. K-nearest neighbour classification further validated the clinico-anatomical correlates emphasizing the functional importance of identified neural substrates with area under the receiving operating characteristic curves between 0.67 and 0.91. Overall, we were able to localize acute effects of hypothalamic region stimulation to distinct tracts and nuclei within the hypothalamus and the wider diencephalon providing clinico-anatomical insights that may help to guide future neuromodulation work.

Background: Hangman’s fractures comprise approximately 20% of C2 fractures and often require surgery to correct significant angulation and/or subluxation. Recently, anchored anterior cervical cages (ACCs) have been used to fuse C2-3 as they reduce the risks of soft-tissue dissection, bone drilling, operative time, and postoperative dysphagia. Methods: This single-center and retrospective study (2012–2019) included 12 patients (3 type I, 6 type II, and 3 type IIa fractures) undergoing C2-3 ACCs (zero profile, half plate, full plate). Preoperative and postoperative radiographic and clinical data were analyzed. Results: The 12 patients demonstrated the following findings: a mean operative time of 106 ± 21 min, blood loss averaging 67 ± 58 mL, and mean length of stay of 9.8 ± 7.7 days (6.4 ± 5.5 days in intensive care). The mean differences in preoperative versus postoperative radiographs showed an increase in disc angle (9.0° ± 9.4° vs. 14.0° ± 7.2°), reduction of subluxation (18.5% ± 13.6% vs. 2.6% ± 6.2%), and maintenance of C2-7 lordosis (14.3° ± 9.5° vs. 14.4° ± 9.5°). All patients demonstrated fusion on dynamic films obtained >6 months postoperatively. In addition, only one patient had Grade 0 subsidence, three had transient postoperative dysphagia, whereas none had either intraoperative complications or 90-day readmissions. Conclusion: ACCs proved to be a viable alternative to traditional anterior cervical discectomy/fusion to treat 12 patients with C2-3 hangman’s fractures in this preliminary study.

BACKGROUND: The COVID-19 pandemic has significantly affected patient care across specialties. Ramifications for neurosurgery include substantial disruptions to surgical training and changes in nonurgent patient presentations to the emergency department. This study quantifies the effects of the COVID-19 pandemic on the number of emergency department patients who were referred to the neurosurgery department for further consultation and treatment and identifies and describes trends in the characteristics of these visits. METHODS: A retrospective review was performed of neurosurgical consultations at a single high-volume institution for 28 call-day periods before and after the official announcement of the pandemic. Primary outcomes included consultations per call-day, patient presentation category, and patient admission. RESULTS: The neurosurgical service was consulted regarding 629 patients (367 male patients) during the study period, with 471 (75%) and 158 (25%) patients presenting before and after the announcement of the COVID-19 pandemic, respectively. The mean number of neurosurgical consultations per call-day was significantly lower in the COVID-19 period (5.6 consultations) compared with the pre-COVID-19 period (16.8 consultations) (P < 0.001). After adjusting for patient demographics, the rate of presentation for general nonurgent concerns, such as back pain, headaches, and other general weaknesses, significantly decreased (odds ratio [95% confidence interval], 0.60 [0.47-0.77], P < 0.001). CONCLUSIONS: Neurosurgical consultations significantly decreased after the onset of the COVID-19 pandemic, with a substantially lower overall number of consultations necessitating operative interventions. Furthermore, the relative number of patients with nonemergent neurological conditions significantly decreased during the pandemic.

espanolSe analiza el cuento “Opus 123”, de la escritora mexicana Ines Arredondo siguiendo parte de la metodologia del semiologo ruso Iuri Lotman. En el texto se aborda, de acuerdo con las categorias de Lotman, la disidencia sexual y en los dos personajes principales masculinos del cuento; ademas de la memoria transgeneracional en los actantes del texto. EnglishThe story "Opus 123" by the Mexican writer Ines Arredondo is analyzed following part of the methodology of the Russian semiologist Iuri Lotman. The text addresses, according to the categories of Lotman, the sexual dissidence and the two main male characters of the story; besides the transgenerational memory in the actants of the text.

The cell division cycle 25A (CDC25A) phosphatase is a key regulator of cell cycle progression that acts on the phosphorylation status of Cyclin-Cyclin-dependent kinase complexes, with an emergent role in the DNA damage response and cell survival control. The regulation of CDC25A activity and its protein level is essential to control the cell cycle and maintain genomic integrity. Here we describe a novel ubiquitin/proteasome-mediated pathway negatively regulating CDC25A stability, dependent on its phosphorylation by the serine/threonine kinase DYRK2. DYRK2 phosphorylates CDC25A on at least 7 residues, resulting in its degradation independent of the known CDC25A E3 ubiquitin ligases. CDC25A in turn is able to control the phosphorylation of DYRK2 at several residues outside from its activation loop, thus affecting DYRK2 localization and activity. An inverse correlation between DYRK2 and CDC25A protein amounts was observed during cell cycle progression and in response to DNA damage, with CDC25A accumulation responding to the manipulation of DYRK2 levels or activity in either physiological scenario. Functional data show that the pro-survival activity of CDC25A and the pro-apoptotic activity of DYRK2 could be partly explained by the mutual regulation between both proteins. Moreover, DYRK2 modulation of CDC25A expression and/or activity contributes to the DYRK2 role in cell cycle regulation. Altogether, we provide evidence suggesting that DYRK2 and CDC25A mutually control their activity and stability by a feedback regulatory loop, with a relevant effect on the genotoxic stress pathway, apoptosis, and cell cycle regulation. This work was funded by Ministerio de Ciencia e Innovación (SAF2016-75228-R to MAC and BFU2016-76141-P to SdlL) and by Cancer Research UK (C52419/A22869) to LdlV. MLC and ACS were supported by a FPU fellowship (FPU13/03393 and FPU18/00845, respectively) from the Ministerio de Educación y Formación Profesional.

Deep brain stimulation (DBS) to the fornix is an investigational treatment for patients with mild Alzheimer’s Disease. Outcomes from randomized clinical trials have shown that cognitive function improved in some patients but deteriorated in others. This could be explained by variance in electrode placement leading to differential engagement of neural circuits. To investigate this, we performed a post-hoc analysis on a multi-center cohort of 46 patients with DBS to the fornix (NCT00658125, NCT01608061). Using normative structural and functional connectivity data, we found that stimulation of the circuit of Papez and stria terminalis robustly associated with cognitive improvement (R = 0.53, p R = 0.48, p R = 0.48, p

En los últimos años, la mejora de las técnicas de criopreservación y la diferencia de legislación entre distintos países en materia de reproducción asistida, ha propiciado que se produzca un importante flujo e intercambio de pacientes y de material biológico reproductivo entre clínicas nacionales e internacionales. España es uno de los países mejor legislados en materia de obtención, manejo, almacenaje y distribución de células y tejidos con carácter reproductivo, aunque estén bajo el paraguas de las normativas marcadas por la Unión Europea, de rango superior a las nacionales. Estas leyes, junto con las recomendaciones de las distintas sociedades científicas regulan el traslado de prembriones humanos, ovocitos o semen. Se establecen así, las condiciones técnicas para estos traslados y la documentación que cada parte del proceso (pacientes, clínica de origen, clínica de destino y empresa de transporte) está obligada a aportar con el fin de garantizar la correcta viabilidad de las muestras y, muy importante, la trazabilidad de estas desde su obtención hasta el laboratorio de destino.

Objective Postoperative peri-lead edema (PLE) is a poorly understood complication of deep brain stimulation (DBS), which has been described sporadically in patients presenting with profound and often delayed symptoms. We performed a prospective evaluation of patients undergoing DBS to determine the frequency of and identify risk factors for PLE. Methods Patients underwent DBS electrode placement by a single physician. Postoperative magnetic resonance imaging (MRI) was performed approximately 6 weeks after the operation in asymptomatic subjects and analyzed for presence of PLE. All symptomatic subjects underwent MRI at the time of presentation. Data regarding index disease, preoperative medical issues, operative technique, and intraoperative variables were collected and statistically analyzed. Results A total of 191 leads were placed in 102 subjects; 15 patients (14.7%) demonstrated PLE. Seven patients (6.9%) presented with symptoms related to PLE, most often altered mental status or neurologic deficit. Many of the MRI findings were profound, with PLE sometimes several centimeters in diameter. No statistically significant difference was found between PLE-positive and normal subjects when analyzing multiple variables, including presence of vascular disease, hypertension, anticoagulant/antiplatelet use, electrode target, index disease, unilateral versus bilateral lead placement, number of brain penetrations, and presence or absence of microelectrode recording. Conclusions Patients with postoperative PLE can present with severe symptoms or can be asymptomatic and go undiagnosed. Because of the delayed-onset potential, PLE may be more common than previously reported. No clear risk factors have been identified; therefore, further studies and increased clinical vigilance are paramount for improving comprehension and possible prevention of PLE.

Deep Brain Stimulation (DBS) is a stimulating therapy currently used to treat the motor disabilities that occur as a result of Parkinson's disease (PD). The mechanism of how DBS treats PD is poorly understood. Currently, there is a paucity of data from in-vivo human studies on the electromagnetic field (EMF) generated within neural tissue by DBS. In this study, the EMF generated by DBS was analyzed at different distances from the stimulating electrodes. Our goal was to examine how the EMF strength changed with distance in the human brain. The resulting analysis demonstrated differences of several orders of magnitude across the distances measured. With further study, we aim to connect the EMF effect on neural structures to the efficacy of DBS treatment.

La meta principal ha sido conceptualizar antropológicamente la cultura ballenera y sus múltiples etapas de desarrollo en península de Baja California, mostrando la importancia socioeconómica que tienen los cetáceos en los sistemas culturales regionales. Como arqueólogos, recabamos datos materiales necesarios que nos permiten iluminar la historia y la importancia histórica sociocultural y económica de la cultura ballenera regional de Baja California Sur y los modos de vida asociados, por medio de recorridos de superficie que nos permitieron identificar las áreas de actividad asociadas. Posteriormente, registramos los relatos etnográficos que nos ayudan a comprender los cambios y las adaptaciones dadas en la cultura ballenera, teniendo como objeto de estudio los modos de interacción H-C histórica, poniendo en perspectiva las expresiones contemporáneas de esta cultura en Baja California Sur.

OBJECTIVE Spinal cord stimulation (SCS) has been shown to be a safe and effective therapy for patients with chronic pain. However, some patients do not obtain or maintain adequate pain relief after SCS. The goal of this study was to identify factors that affect patient outcome with regard to SCS. MATERIALS AND METHODS A retrospective analysis of electronic medical records at a single site was performed. Records for 181 patients who received SCS implants from 2014 through 2016 were collected with follow-up data captured up to August 2019. Patient outcome was measured by device explantation and patient benefit from the SCS. Study parameters included demographic characteristics, history of pain, SCS implant characteristics, and postimplantation events. RESULTS An earlier diagnosis of radiculopathy was associated with an increased risk of poor benefit (relative risk [RR], 1.81; 95% CI, 1.19-2.74; p = 0.008). Postimplantation falls were associated with an increased risk of poor benefit (RR, 2.17; 95% CI, 1.48-3.17; p = 0.009). Device manufacturer was associated with both patient benefit and explantation. Device 2 was associated with a reduced risk of poor benefit (RR, 0.52; 95% CI, 0.32-0.85; p = 0.009). Device 4 was associated with an increased risk of poor benefit (RR, 1.71; 95% CI, 1.14-2.55; p = 0.02) and increased risk of device explantation (RR, 2.69; 95% CI, 1.2-6.02; p = 0.03). CONCLUSIONS Patient outcome was associated with diagnosis, postimplantation falls, and device manufacturer. Further investigation is recommended to confirm associations through prospective studies that can more accurately quantify patient outcome over longer periods.

Background: To date, there are only six published reports of adductor spasmodic dysphonia (SD) responding to awake thalamic deep brain stimulation (DBS). Methods: We retrospectively reviewed cases of Essential Tremor (ET) with SD that were seen in our center from 2012 to 2020. We further identified those that have undergone thalamic DBS, and had a blinded laryngologist rate first the audio voice recordings before and after DBS using the Unified Spasmodic Dysphonia Rating Scale (USDRS), and the video recordings last to rate the related movements and facial grimacing. Results: We identified three cases of adductor SD with ET that had undergone bilateral ventralis intermedius (VIM) DBS under general anesthesia. All patients noted improvement of their limb and voice tremor, as well as their SD post-DBS. Although improvement of tremor was observed even with initial programming in all three, improvement of SD was noted only upon reaching higher amplitudes or wider pulse widths. Blinded voice assessments showed improvement of USDRS scores post-DBS compared to pre-DBS, and with stimulator on compared to stimulator off. Discussion: We report the first three cases of SD responding favorably to bilateral VIM asleep DBS and summarize the nine cases so far of SD who have undergone thalamic DBS.

Background: To date, there have been no reports of tardive blepharospasm being treated with deep brain stimulation (DBS), though there have been two reports of focal blepharospasm responding favorably to bilateral pallidal DBS. Case: A 34 year old man with tardive blepharospasm that was refractory to oral medications as well as botulinum toxin types A and B underwent bilateral pallidal DBS under general anesthesia. He had significant improvement of his severe blepharospasm by one and half months post-DBS which was sustained at last follow-up 30 months post-DBS. The best programming parameters included pulse widths of 90–100 μsec, frequencies of 140–150 Hz, and stimulating the ventral contacts in each side. Conclusion: Our case represents the first report of medically refractory tardive blepharospasm responding favorably to bilateral pallidal DBS.

OBJECTIVE The ventral intermediate nucleus of the thalamus (VIM) is an effective target for deep brain stimulation (DBS) to control symptoms related to essential tremor. The VIM is typically targeted using indirect methods, although studies have reported visualization of the VIM on proton density–weighted MRI. This study compares the outcomes between patients who underwent VIM DBS with direct and indirect targeting. METHODS Between August 2013 and December 2019, 230 patients underwent VIM DBS at the senior author’s institution. Of these patients, 92 had direct targeting (direct visualization on proton density 3-T MRI). The remaining 138 patients had indirect targeting (relative to the third ventricle and anterior commissure–posterior commissure line). RESULTS Coordinates of electrodes placed with direct targeting were significantly more lateral (p < 0.001) and anterior (p < 0.001) than those placed with indirect targeting. The optimal stimulation amplitude for devices measured in voltage was lower for those who underwent direct targeting than for those who underwent indirect targeting (p < 0.001). Patients undergoing direct targeting had a greater improvement only in their Quality of Life in Essential Tremor Questionnaire hobby score versus those undergoing indirect targeting (p = 0.04). The direct targeting group had substantially more symptomatic hemorrhages than the indirect targeting group (p = 0.04). All patients who experienced a postoperative hemorrhage after DBS recovered without intervention. CONCLUSIONS Patients who underwent direct VIM targeting for DBS treatment of essential tremor had similar clinical outcomes to those who underwent indirect targeting. Direct VIM targeting is safe and effective.

Background Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) is a severe headache disorder characterized by clustered episodes of extreme pain. Refractory to most interventions, ipsilateral unilateral ventral tegmental area (VTA) deep brain stimulation (DBS) has been previously reported to be efficacious in 14 cases. Methods and results Herein, we report the first case of an individual with medically refractory SUNCT who underwent bilateral VTA DBS. The patient experienced better improvement of his headaches with bilateral stimulation compared to unilateral stimulation. He also had a return of severe headaches within a few hours after his stimulator was switched off during sleep, with rebound worsening of his headaches over several days. The main side effects were double vision and difficulty focusing while reading, which were observed primarily with unipolar stimulation that required high voltages, high frequencies, and multiple negative contacts to control the headaches. The side effects were minimized with bipolar and interleaving stimulation with comparable control of his headaches. Conclusion Bilateral VTA DBS may be effective in alleviating medical refractory SUNCT.

OBJECTIVEDeep brain stimulation (DBS) is an elective procedure that can dramatically enhance quality of life. Because DBS is not considered lifesaving, it is important that providers produce consistently good outcomes, and one factor they usually consider is patient age. While older age may be a relative contraindication for some elective surgeries, the progressive nature of movement disorders treated with DBS may suggest that older patients stand to benefit substantially from surgery. To better understand the risks of treating patients of advanced age with DBS, this study compares perioperative complication rates in patients ≥ 75 to those < 75 years old.METHODSPatients undergoing DBS surgery for various indications by a single surgeon (May 2013–July 2019) were stratified into elderly (age ≥ 75 years) and younger (age < 75 years) cohorts. The risks of common perioperative complications and various outcome measures were compared between the two age groups using risk ratios (RRs) and 95% confidence intervals (CIs).RESULTSA total of 861 patients were available for analysis: 179 (21%) were ≥ 75 years old and 682 (79%) were < 75 years old (p < 0.001). Patients ≥ 75 years old, compared with those < 75 years old, did not have significantly different RRs (95% CIs) of seizure (RR 0.4, 95% CI 0.1–3.3), cerebrovascular accident (RR 1.9, 95% CI 0.4–10.3), readmission within 90 days of discharge (RR 1.22, 95% CI 0.8–1.8), explantation due to infection (RR 2.5, 95% CI 0.4–15.1), or surgical revision (for lead, RR 2.5, 95% CI 0.4–15.1; for internal pulse generator, RR 3.8, 95% CI 0.2–61.7). Although the risk of postoperative intracranial bleeding was higher in the elderly group (6.1%) than in the younger group (3.1%), this difference was not statistically significant (p = 0.06). However, patients ≥ 75 years old did have significantly increased risk of altered mental status (RR 2.5, 95% CI 1.6–4.0), experiencing more than a 1-night stay (RR 1.7, 95% CI 1.4–2.0), and urinary retention (RR 2.3, 95% CI 1.2–4.2; p = 0.009).CONCLUSIONSAlthough elderly patients had higher risks of certain outcome measures than younger patients, this study showed that elderly patients undergoing DBS for movement disorders did not have an increased risk of more serious complications, such as intracranial hemorrhage, infection, or readmission. Advanced age alone should not be considered a contraindication for DBS.

Appropriate patient selection is critical for successful deep brain stimulation (DBS) for Parkinson disease (PD). Subcortical atrophy is a possible determinant of postoperative DBS outcomes in patients with idiopathic PD, but it has not been well evaluated for DBS of the globus pallidus interna (GPi). We investigated perioperative subcortical atrophy measures in patients with PD and their relationship to postoperative motor response in bilateral GPi-targeted DBS.A retrospective cohort study examined correlations among indices of subcortical volumetry, disease duration, and age with postoperative outcomes at 6 months (Unified Parkinson's Disease Rating Scale Part III motor score quotient, levodopa equivalent daily dosing, and 39-item Parkinson's Disease Questionnaire mobility subscore). Subcortical volumetry was assessed by bicaudate ratio, Evans index, and third ventricular width on perioperative imaging. Linear regression models established correlations between preoperative variables and postoperative outcomes.Data from 34 patients with PD who were treated with GPi-targeted DBS were evaluated. Age was found to exhibit statistically significant positive correlations with all 3 measures of subcortical atrophy (P ≤ 0.002). None of the measures correlated with disease duration. Only Evans index and third ventricular width correlated with preoperative medication response (P0.05). Age and all 3 measures of atrophy exhibited statistically significant correlations with Unified Parkinson's Disease Rating Scale Part III motor score quotient (P ≤ 0.01), but not with levodopa equivalent daily dosing or 39-item Parkinson's Disease Questionnaire motor subscores (P0.05).Perioperative age and subcortical atrophy as measured in this study correlated with motor responsiveness at 6 months postoperatively among patients receiving bilateral GPi-targeted DBS stimulation for PD.

The availability of intraoperative computed tomography (CT) and magnetic resonance imaging (MRI) in neurosurgery has steadily grown over the past 15 years. CT scanners are used routinely for the placement of spinal instrumentation, while intraoperative MRI is used in brain tumor surgery to assess degree of resection. These imaging platforms are increasingly being incorporated into deep brain stimulation (DBS) surgery. Common data points for determining final lead placement in DBS surgery are test stimulation of the lead—to determine clinical benefit and side effects—and microelectrode recording (MER). Intraoperative three-dimensional imaging allows the surgeon to quantify stereotactic accuracy at the time of surgery. While intraoperative CT and MRI can be used in conjunction with test stimulation and MER, there has been a growing interest in using stereotactic accuracy alone in determining target engagement. As this approach to DBS surgery evolves, the role of intraoperative CT and MRI in DBS surgery will become increasingly fundamental.

OBJECTIVEVentral intermediate nucleus deep brain stimulation (DBS) for essential tremor is traditionally performed with intraoperative test stimulation and conscious sedation, without general anesthesia (GA). Recently, the authors reported retrospective data on 17 patients undergoing DBS after induction of GA with standardized anatomical coordinates on T1-weighted MRI sequences used for indirect targeting. Here, they compare prospectively collected data from essential tremor patients undergoing DBS both with GA and without GA (non-GA).METHODSClinical outcomes were prospectively collected at baseline and 3-month follow-up for patients undergoing DBS surgery performed by a single surgeon. Stereotactic, euclidean, and radial errors of lead placement were calculated. Functional (activities of daily living), quality of life (Quality of Life in Essential Tremor [QUEST] questionnaire), and tremor severity outcomes were compared between groups.RESULTSFifty-six patients underwent surgery: 16 without GA (24 electrodes) and 40 with GA (66 electrodes). The mean baseline functional scores and QUEST summary indices were not different between groups (p = 0.91 and p = 0.59, respectively). Non-GA and GA groups did not differ significantly regarding mean postoperative percentages of functional improvement (non-GA, 47.9% vs GA, 48.1%; p = 0.96) or QUEST summary indices (non-GA, 79.9% vs GA, 74.8%; p = 0.50). Accuracy was comparable between groups (mean radial error 0.9 ± 0.3 mm for non-GA and 0.9 ± 0.4 mm for GA patients) (p = 0.75). The mean euclidean error was also similar between groups (non-GA, 1.1 ± 0.6 mm vs GA, 1.2 ± 0.5 mm; p = 0.92). No patient had an intraoperative complication, and the number of postoperative complications was not different between groups (non-GA, n = 1 vs GA, n = 10; p = 0.16).CONCLUSIONSDBS performed with the patient under GA to treat essential tremor is as safe and effective as traditional DBS surgery with intraoperative test stimulation while the patient is under conscious sedation without GA.

espanolEste trabajo estudia el caso de un texto de Rene Aviles Fabila que fue publicado en un medio politico y de ahi paso a formar parte de la historia de la literatura mexicana. En el estudio se revisan los fenomenos que permiten que un texto, sin modificar su contenido, pase de un genero a otro. La peculiar composicion del texto en cuestion motiva reflexiones respecto al ser de la literatura EnglishThis work studies the case of a text by Rene Aviles Fabila that was published in a political medium and from there it became part of the history of Mexican literature. The study reviews the phenomena that allow a text, without changing its content, to pass from one genre to another. The peculiar composition of the text in question motivates reflections on the being of literature

OBJECTIVERecent studies have shown similar clinical outcomes between Parkinson disease (PD) patients treated with deep brain stimulation (DBS) under general anesthesia without microelectrode recording (MER), so-called “asleep” DBS, and historical cohorts undergoing “awake” DBS with MER guidance. However, few studies include internal controls. This study aims to compare clinical outcomes after globus pallidus internus (GPi) and subthalamic nucleus (STN) DBS using awake and asleep techniques at a single institution.METHODSPD patients undergoing awake or asleep bilateral GPi or STN DBS were prospectively monitored. The primary outcome measure was stimulation-induced change in motor function off medication 6 months postoperatively, measured using the Unified Parkinson’s Disease Rating Scale part III (UPDRS-III). Secondary outcomes included change in quality of life, measured by the 39-item Parkinson’s Disease Questionnaire (PDQ-39), change in levodopa equivalent daily dosage (LEDD), stereotactic accuracy, stimulation parameters, and adverse events.RESULTSSix-month outcome data were available for 133 patients treated over 45 months (78 GPi [16 awake, 62 asleep] and 55 STN [14 awake, 41 asleep]). UPDRS-III score improvement with stimulation did not differ between awake and asleep groups for GPi (awake, 20.8 points [38.5%]; asleep, 18.8 points [37.5%]; p = 0.45) or STN (awake, 21.6 points [40.3%]; asleep, 26.1 points [48.8%]; p = 0.20) targets. The percentage improvement in PDQ-39 and LEDD was similar for awake and asleep groups for both GPi (p = 0.80 and p = 0.54, respectively) and STN cohorts (p = 0.85 and p = 0.49, respectively).CONCLUSIONSIn PD patients, bilateral GPi and STN DBS using the asleep method resulted in motor, quality-of-life, and medication reduction outcomes that were comparable to those of the awake method.

OBJECTIVEAs the number of deep brain stimulation (DBS) procedures performed under general anesthesia (“asleep” DBS) increases, it is more important to assess the rates of adverse events, inpatient lengths of stay (LOS), and 30-day readmission rates in patients undergoing these procedures compared with those in patients undergoing traditional “awake” DBS without general anesthesia.METHODSAll patients in an institutional database who had undergone awake or asleep DBS procedures performed by a single surgeon between August 2011 and August 2014 were reviewed. Adverse events, inpatient LOS, and 30-day readmissions were analyzed.RESULTSA total of 490 electrodes were placed in 284 patients, of whom 126 (44.4%) underwent awake surgery and 158 (55.6%) underwent asleep surgery. The most frequent overall complication for the cohort was postoperative mental status change (13 patients [4.6%]), followed by hemorrhage (4 patients [1.4%]), seizure (4 patients [1.4%]), and hardware-related infection (3 patients [1.1%]). Mean LOS for all 284 patients was 1.19 ± 1.29 days (awake: 1.06 ± 0.46 days; asleep: 1.30 ± 1.67 days; p = 0.08). Overall, the 30-day readmission rate was 1.4% (1 awake patient, 3 asleep patients). There were no significant differences in complications, LOS, and 30-day readmissions between awake and asleep groups.CONCLUSIONSBoth awake and asleep DBS can be performed safely with low complication rates. The authors found no significant differences between the 2 procedure groups in adverse events, inpatient LOS, and 30-day readmission rates.

Background Bibliometric analyses based on total citation count come with many limitations, which investigators in other fields have overcome using the average number of citations per year since publication. Method The following study is presented in 2 parts. In this first part, the 100 most relevant articles in neurosurgical journals were identified and ranked by total citations per year since publication. We queried the Web of Science database for the 1000 most-cited articles in neurosurgical journals. The number of citations per year was calculated for these 1000 articles, and the top 100 were identified. Results Among the top 100 most relevant articles, 63 were from the Journal of Neurosurgery, 26 from Neurosurgery, 7 from the Journal of Neurology, Neurosurgery, and Psychiatry, 3 from Acta Neurochirurgica, and 1 from Surgical Neurology. The average year of publication for the 100 most relevant articles is 1995, compared with 1984 for the list of most-cited articles published by Ponce and Lozano in 2010 (P Conclusion These results suggest that ranking articles based on relevancy rather than historical popularity results in a list of more recently published articles and includes more studies addressing topics of surgical management and outcomes. The ability to appraise the literature in this fashion is worthwhile to those seeking a better understanding of the science underlying modern clinical practice and is thus a highly valuable tool for neurosurgical residents, program directors, and neuroscientists as they acquire an understanding of modern neurosurgery and its scientific foundation.

High-frequency deep brain stimulation (DBS) was introduced in the late 1980s for the treatment of movement disorders. This reversible, adjustable, and non-ablative therapy has been used to treat more than 100,000 people worldwide. The surgical procedure used to implant the DBS system, as well as the effects of chronic electrical stimulation, have been shown to be safe and effective through many clinical trials. Given the ability to therapeutically modulate the motor circuits of the brain in this manner, clinicians have considered using DBS for other neurodegenerative and neuropsychiatric disorders involving non-motor circuits, including appetite, mood, and cognition. This article highlights several recent studies exploring the feasibility of using DBS to modulate memory, specifically in the context of memory disorders such as Alzheimer disease.