Lumbosacral DREZotomy for oncologic pain treatment: a case-based review.

PURPOSE: To present 3 cases of oncologic pain treated by DREZotomy in the pediatric population and to review the literature published about this procedure. METHODS: The permanent literature about oncologic pain treatment in children and the applicability of DREZotomy was reviewed. Three cases treated at our institution were reviewed and presented. RESULTS: In the pediatric population, the DREZotomy has been extensively applied for the treatment of spasticity and spasticity-related pain. Currently, there are no reports of oncologic pain treated by means of a DREZotomy in children. We presented 3 cases coursing the terminal stage of illness, presenting predominantly neuropathic, oncologic pain that were successfully managed after a DREZotomy was performed. CONCLUSION: In well-selected patients, with a good general condition and life expectancy to withstand an open neurosurgical procedure, DREZotomy is an excellent tool to treat neuropathic oncologic pain.

Timing of treatment in osteosarcoma: challenges and perspectives - a scoping review.

BACKGROUND: The timing of events in the management of osteosarcoma may be critical for patient survivorship; however, the prognostic value of factors such as onset of symptoms or initiation of therapy in these patients has not been studied. This study sought to review the literature reporting treatment of osteosarcoma to determine the utility of event timing as a prognostic indicator. Due to significant heterogeneity in the literature, this study was conducted as a scoping review to assess the current state of the literature, identify strengths and weaknesses in current reporting practices, and to propose avenues for future improvement. MAIN BODY: This review screened 312 peer-reviewed studies of osteosarcoma in any anatomic location published in an English journal for reporting of an event timing metric of any kind in a population of 6 or more. Thirty-seven studies met inclusion/exclusion criteria and were assessed for level of evidence, quality, and event timing metric. Reviewers also collated: publication year, population size, population age, tumor site, tumor type, surgical treatment, and adjuvant medical treatment. Extracted event timing data were further characterized using nine standardized categories to enable systematic analysis. The reporting of event timing in the treatment of osteosarcoma was incomplete and heterogenous. Only 37 of 312 (11.9%) screened studies reported event timing in any capacity. The period between patient-reported symptom initiation and definitive diagnosis was the most reported (17/37, 45.9%). Symptom duration was the second most reported period (10/37, 27.0%). Event timing was typically reported incidentally and was never rigorously incorporated into data analysis or discussion. No studies considered the impact of event timing on a primary outcome. The six largest studies were assessed in detail to identify pearls for future researchers. Notable shortcomings included the inadequate reporting of the definition of an event timing period and the pooling of patients into poorly defined timing groups. CONCLUSIONS: Inconsistent reporting of event timing in osteosarcoma treatment prevents the development of clinically useful conclusions despite evidence to suggest event timing is a useful prognostic indicator. Consensus guidelines are necessary to improve uniformity and utility in the reporting of event timing.

Low-Intensity Pulsed Ultrasound Augments Tendon, Ligament, and Bone-Soft Tissue Healing in Preclinical Animal Models: A Systematic Review.

PURPOSE: To appraise the available animal and human studies investigating low-intensity pulsed ultrasound stimulation (LIPUS) on tendon, ligament, and bone-soft tissue (B-ST) junction healing. METHODS: A systematic review of PUBMED, EMBASE, and the Cochrane Library was performed for animal and human studies investigating the effects of LIPUS on tendon, ligament, and B-ST junction healing. The systematic search was performed using the key term "low intensity pulsed ultrasound" and any of the following: "tendon," "ligament," "tendon-bone," and "bone-tendon." Inclusion criteria consisted of (1) randomized controlled trials assessing the effect of LIPUS on bone, tendon, and soft tissue in animals or humans and (2) English-language articles. RESULTS: A total of 28 animal and 2 human studies met inclusion criteria. Animal studies utilized various models, including Achilles and patellar tendon transections, medial collateral ligament transections, and surgical repair of patellar tendon, rotator cuff tendon, and anterior cruciate ligament, to evaluate the effects of LIPUS. Animal studies demonstrated significantly improved collagen content and organization, bone formation, fibrocartilage remodeling, and mechanical strength with LIPUS treatment compared with controls. In human trials, LIPUS treatment of chronic tendinopathies did not improve clinical outcomes. CONCLUSIONS: In acute injury animal models, LIPUS augmented healing of acute tendon, ligament, and B-ST junction injuries through increased collagen content and organization; increased anti-inflammatory cellular signaling; and increased angiogenesis. However, in 2 human studies investigating chronic tendinopathy, LIPUS did not lead to superior outcomes compared with controls. CLINICAL RELEVANCE: Animal models suggest that LIPUS may be a promising noninvasive treatment modality for accelerating patient recovery after acute tendon and ligament injuries, as well as after surgical repair of B-ST junction injuries, but this has not been demonstrated in human studies. Randomized clinical trials evaluating LIPUS for acute tendon and ligament injuries are warranted.

Surgical anatomy of the axillary artery: clinical implications for open shoulder surgery.

BACKGROUND: Axillary artery injury is a devastating complication related to anterior shoulder surgery and can result in significant morbidity and/or mortality. The purpose of our study was to evaluate the course of the axillary artery in relation to bony landmarks of the shoulder and identify variations in artery position with humeral external rotation. MATERIALS AND METHODS: Dissection of 18 shoulders (9 fresh whole-body cadavers) with simulated vessel perfusion using radiopaque dye was performed. The axillary artery position was measured from multiple points including 2 points on the coracoid base (C1 and C2), 3 points on the coracoid tip (C3-C5), 4 points on the glenoid: superior, middle, and inferior glenoid (D1-D4), and 2 points on the lesser tuberosity (L1 and L2). Fluoroscopic measurements were taken and compared at 0° and 90° of external rotation (F1 vs. F1' and F2 vs. F2'). Manual and fluoroscopic measurements were compared with one another using Kendall's τb correlation. RESULTS: There were 6 male and 3 female cadavers with an average age of 67.2 ± 9.3 years (range: 49-77 years). The mean distance from the axillary artery to the coracoid base (C1 and C2) measured 21.1 ± 7.3 and 22.3 ± 7.4 mm, respectively, whereas the mean distance to the coracoid tip (C3, C4, and C5) measured 30.7 ± 9.3, 52.1 ± 20.2, and 46.5 ± 14.3 mm, respectively. Measurements relative to the glenoid face (D1, D2, and D3) showed a progressive decrease in mean distance from superior to inferior, measuring 31.6 ± 10.3, 16.5 ± 7.5, and 10.3 ± 7.3 mm, respectively, whereas D4 (inferior glenoid to axillary artery) measured 17.8 ± 10.7 mm. The minimum distance from the axillary artery to any point on the glenoid was as close as 4.1 mm (D3). There was a statistically significant difference in F1 (0° external rotation) vs. F1' (90° external rotation) (18.5 vs. 13.4 mm, P = .03). Kendall's τb correlation showed a strong, positive correlation between manual and fluoroscopic measurements (D4: 16.0 ± 12.5 mm vs. F1: 18.5 ± 10.7 mm) (τb = 0.556, P = .037). CONCLUSION: The axillary artery travels an average of 1-1.8 cm from the inferior glenoid margin, which puts the artery at significant risk. In addition, the artery is significantly closer to the inferior glenoid with humeral external rotation. Surgeons performing anterior shoulder surgery should have a thorough understanding of the axillary artery course and understand changes in the position of the artery with external rotation of the humerus.

Pyrobaculum igneiluti sp. nov., a novel anaerobic hyperthermophilic archaeon that reduces thiosulfate and ferric iron.

A novel anaerobic, hyperthermophilic archaeon was isolated from a mud volcano in the Salton Sea geothermal system in southern California, USA. The isolate, named strain 521T, grew optimally at 90 °C, at pH 5.5-7.3 and with 0-2.0 % (w/v) NaCl, with a generation time of 10 h under optimal conditions. Cells were rod-shaped and non-motile, ranging from 2 to 7 µm in length. Strain 521T grew only in the presence of thiosulfate and/or Fe(III) (ferrihydrite) as terminal electron acceptors under strictly anaerobic conditions, and preferred protein-rich compounds as energy sources, although the isolate was capable of chemolithoautotrophic growth. 16S rRNA gene sequence analysis places this isolate within the crenarchaeal genus Pyrobaculum. To our knowledge, this is the first Pyrobaculum strain to be isolated from an anaerobic mud volcano and to reduce only either thiosulfate or ferric iron. An in silico genome-to-genome distance calculator reported <25 % DNA-DNA hybridization between strain 521T and eight other Pyrobaculum species. Due to its genotypic and phenotypic differences, we conclude that strain 521T represents a novel species, for which the name Pyrobaculum igneiluti sp. nov. is proposed. The type strain is 521T (=DSM 103086T=ATCC TSD-56T).

Spatial Anatomy of the Radial Nerve in the Extended Deltopectoral Approach.

The goal of this study was to define safe zones to prevent radial nerve injury in an extended deltopectoral approach. Relative distances of the upper margin (UMRN) and lower margin (LMRN) of the radial nerve to the proximal and distal borders of the pectoralis major and deltoid insertions were measured in 20 cadaveric arms. Four proximal humeral zones were identified (zone I, proximal border of the pectoralis major tendon to the proximal border of the deltoid tendon; zone II, proximal border of the deltoid tendon to the distal border of the pectoralis major tendon; zone III, distal border of the pectoralis major tendon to the distal border of the deltoid tendon; and zone IV, distal to the distal border of the deltoid tendon). On fluoroscopic measurement, mean distances between the UMRN and the proximal border of the pectoralis major tendon and the proximal border of the deltoid tendon were 71.6±2.1 mm and 26.2±2.5 mm, respectively. The incidence of the radial nerve in the spiral groove within each defined zone was as follows: zone I, 0%; zone II, 50%; zones III and IV, 100%. There was a significant association between anatomic zone and radial nerve entry into the spiral groove, χ2(3, N=88)=64.53, P<.001. The proximal border of the pectoralis major tendon to the proximal border of the deltoid tendon (zone I) is a safe location to avoid injury to the radial nerve. We recommend placing cerclage wires proximal to zone I from lateral to medial to avoid entrapment of the radial nerve. [Orthopedics. 2023;46(1):e31-e37.].

Total joint replacement surgeon choice: A qualitative analysis in a medicare population.

INTRODUCTION: Previous research has shown that patients from historically marginalized groups in the United States tend to have poorer outcomes after joint replacement surgery and that they are less likely to receive joint replacement surgery at high-volume hospitals. However, little is known regarding how this group of patients chooses their joint replacement surgeon. The purpose of this study was to understand the factors influencing the choice of joint replacement surgeon amongst a diverse group of patients. METHODS: Semi-structured interviews were conducted with Medicare patients who underwent a hip or knee replacement within the last 24 months (N = 38) at an academic and community hospital. Interviews were audio recorded, transcribed and verified for accuracy. Transcripts were reviewed using iterative content analysis to extract key themes related to how respondents chose their joint replacement surgeon. RESULTS AND DISCUSSION: MD referral/recommendation appears to be the strongest factor influencing joint replacement surgeon choice. Other key considerations are hospital reputation and surgeon attributes-including operative experience, communication skills, and participation in shared decision-making. Gender/ethnicity of a surgeon, industry payments to surgeons, number of publications and cost did not play a large role in surgeon choice. CONCLUSION AND CLINICAL RELEVANCE: The process of choosing a joint replacement surgeon is a complex decision-making process with several factors at play. Despite growing availability of information regarding surgeons, patients largely relied on referrals for choosing their joint replacement surgeon regardless of ethnicity. Referring physicians need to ensure that patients are able to access hospital and surgeon outcomes, operative volume, and industry-payment information to learn more about their orthopedic surgeons in order to make an informed choice.

Approach to the Superior Ophthalmic Vein for Endovascular Treatment of Cavernous Dural Fistula.

The cavernous sinus area is the second most common location for intracranial dural fistulas. Although these spontaneous dural cavernous fistulas are self-limited, a sizeable number of patients will develop progressive vision loss, diplopia, or intractable glaucoma, which warrant interventional therapy.1,2 We present the case of a 54-year-old male with hypertension and type 2 diabetes, who presented with a red right eye associated with progressive exophthalmos, ophthalmoparesis, and deterioration of visual acuity. The angiotomography showed the exophthalmos with an ingurgitated superior ophthalmic vein, with early filling in the arterial phase. A digital angiography was made, and a diagnosis of dural cavernous fistula, Barrow type D was made.3 Considering several transvenous approaches, alternatives included inferior petrosal sinus, access through the superior ophthalmic vein, and an open approach.4 In this particular case the inferior petrosal sinus was not present, so we tried to catheterize through the facial vein and also puncture the ophthalmic vein. Both procedures were unsuccessful. We decided to perform, then, an open approach with the oculoplastic surgery team (Video 1). Through an eyelid dissection, we localized the superior ophthalmic vein and then canalized it by direct visualization.5 With this approach, we were able to perform the cavernous sinus packing with coils and achieved a complete occlusion of the fistula. We reproduced the direct approach to the superior ophthalmic vein in a cadaveric specimen and schematized it step by step with 3-dimensional photographs.6.

A Novel Low-Cost Exoscopy Station for Training Neurosurgeons and Neurosurgery Trainees.

BACKGROUND: The loss of stereopsis and the need for markedly enhanced hand-eye coordination are obstacles to overcome when performing exoscopic procedures, but both should improve with training. Our objectives were to describe an exoscopy training station and to compare time and performance of a given microsurgical technique among neurosurgery residents and junior neurosurgeons. METHODS: We designed a low-cost exoscopy training station featuring a notebook computer, a webcam, and a light-emitting diode source. Surgeons and surgical trainees with no experience in exoscopy were enrolled and divided into 2 groups (trainees and controls). Performance and time in suture placement were evaluated by a skilled observer in both groups at baseline and 3 days later. Between evaluations, trainees completed an exoscopy training module. RESULTS: There were 22 participants divided equally into 2 groups. At baseline, trainees had a greater percentage of proper sutures than controls (58% vs. 35%), but they were also slower (32 minutes vs. 25 minutes). On final evaluation, not only were trainees approximately 14 minutes faster than at baseline (P = 0,03), but also their successful suture rate had increased by 18% (final rate 76%, P = 0.02). Moreover, controls were faster compared with baseline by 6 minutes (P = 0.003), but their percentage of successful sutures did not increase (final rate 38%, P = 0.49). The change from baseline to final evaluation favored trainees for both outcomes (P = 0.03 and P = 0.02). CONCLUSIONS: Using the exoscopy training station, the trainees were able to improve their time and performance of exoscopy compared with the controls.

Blood transfusion rates and predictors following geriatric hip fracture surgery.

BACKGROUND: Postoperative blood product transfusions in elderly hip fracture patients cause concern for morbidity and mortality. The purpose of this study was to identify predictors and short-term sequelae of postoperative transfusion following geriatric hip fracture surgery. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) to identify geriatric (⩾65 years) patients who sustained operative femoral neck, intertrochanteric, and subtrochanteric hip fractures in 2016. Multivariate regression was used to determine risk-adjusted odds ratios (OR) of associated perioperative risk factors and sequelae of postoperative transfusion. RESULTS: In total, 8416 geriatric hip fracture patients were identified of whom 28.3% had documented postoperative transfusion. In multivariate analysis, age (OR 1.03 [1.02-1.04], p < 0.001), preoperative anaemia (OR 4.69 [3.99-5.52], p = 0.001), female sex (OR 1.61 [1.39-1.87], p < 0.001), lower BMI (OR 0.97 [0.96-0.98], p < 0.001), American Society of Anesthesiologists (ASA) classification (OR 1.14 [1.01-1.27], p = 0.031), COPD (OR 1.30 [1.06-1.59], p = 0.011), hypertension (OR 1.17 [1.01-1.35], p = 0.038), increased OR time (OR 1.02 [1.01-1.03], p < 0.001), and intertrochanteric (OR 2.99 [2.57-3.49], p < 0.001) and subtrochanteric femur fractures (OR 5.07 [3.84-6.69], p < 0.001) were independent risk factors for receiving postoperative blood transfusion. Patients with postoperative transfusion had a significantly higher risk-adjusted 30-day mortality (8.4% vs. 6.4%, OR 1.29 [1.02-1.64], p = 0.035), hospital readmission rate (9.4% vs. 7.7%, OR 1.27 [1.04-1.55], p = 0.018), and total hospital LOS (7.3 vs. 6.3 days, p < 0.001). CONCLUSIONS: Postoperative transfusion is a common occurrence in geriatric fragility hip fractures with multiple risk factors. Careful preoperative planning and multidisciplinary management efforts are warranted to reduce use of postoperative transfusions.

Regional Gene Therapy with Transduced Human Cells: The Influence of "Cell Dose" on Bone Repair.

Regional gene therapy using a lentiviral vector containing the BMP-2 complementary DNA (cDNA) has been shown to heal critical-sized bone defects in rodent models. An appropriate "cellular dose" needs to be defined for eventual translation into human trials. The purpose of this study was to evaluate bone defect healing potential and quality using three different doses of transduced human bone marrow cells (HBMCs). HBMCs were transduced with a lentiviral vector containing either BMP-2 or green fluorescent protein (GFP). All cells were loaded onto compression-resistant matrices and implanted in the bone defect of athymic rats. Treatment groups included femoral defects that were treated with a low-dose (1 × 106 cells), standard-dose (5 × 106 cells), and high-dose (1.5 × 107 cells) HBMCs transduced with lentiviral vector containing BMP-2 cDNA. The three control groups were bone defects treated with HBMCs that were either nontransduced or transduced with vector containing GFP. All animals were sacrificed at 12 weeks. The bone formed in each defect was evaluated with plain radiographs, microcomputed tomography (microCT), histomorphometric analysis, and biomechanical testing. Bone defects treated with higher doses of BMP-2-producing cells were more likely to have healed (6/14 of the low-dose group; 12/14 of the standard-dose group; 14/14 of the high-dose group; χ2(2) = 15.501, p < 0.001). None of the bone defects in the control groups had healed. Bone defects treated with high dose and standard dose of BMP-2-producing cells consistently outperformed those treated with a low dose in terms of bone formation, as assessed by microCT and histomorphometry, and biomechanical parameters. However, statistical significance was only seen between defects treated with high dose and low dose. Larger doses of BMP-2-producing cells were associated with a higher likelihood of forming heterotopic ossification. Femurs treated with a standard- and high-dose BMP-2-producing cells demonstrated similar healing and biomechanical properties. Increased doses of BMP-2 delivered through higher cell doses have the potential to heal large bone defects. Adapting regional gene therapy for use in humans will require a balance between promoting bone repair and limiting heterotopic ossification. Impact statement Critical bone loss may result from complex traumatic bone injury (i.e., open fracture or blast injury), revision total joint arthroplasty, and spine pseudoarthrosis. This is a challenging clinical problem to treat and regional gene therapy is an innovative means of addressing it. This study provides information regarding the quantity of cells or "cell dose" of transduced cells needed to treat a critical-sized bone defect in a rat model. This information may be extrapolated for use in humans in future trials.

Postacute Care Utilization in Postsurgical Orthogeriatric Hip Fracture Care.

INTRODUCTION: Among surgical patients, utilization of institutional-based postacute care (PAC) presents a notable financial burden and is associated with increased risk of complications and mortality rates when compared with discharge home. The purpose of this study was to identify predictors of postdischarge disposition to PAC in geriatric patients after surgical fixation of native hip fractures. METHODS: We have done a query of the American College of Surgeons National Surgical Quality Improvement Program to identify geriatric (≥65 years) patients who sustained surgical femoral neck, intertrochanteric, and subtrochanteric hip fractures in 2016. Multivariate regression was used to compute risk factors for discharge to and prolonged stay (>30 days) in PAC. RESULTS: Eight thousand one hundred thirty-three geriatric hip fracture patients with sufficient follow-up data were identified. Of these, 6,670 patients (82.0%) were initially discharged to PAC after their hip fracture episode of care, and 2,986 patients (36.7%) remained in PAC for >30 days. Age (odds ratio [OR] 1.06 [1.05 to 1.08], P < 0.001), partial (OR 2.41 [1.57 to 3.71], P < 0.001) or total dependence (OR 3.03 [1.92 to 4.46], P < 0.001) for activities of daily living, dementia (OR 1.62 [1.33 to 1.96], P < 0.001), diabetes (OR 1.46 [1.14 to 1.85], P = 0.002), hypertension (OR 1.32 [1.10 to 1.58], P = 0.002), and total hospital length of stay (OR 1.04 [1.01 to 1.08], P = 0.006) were independent risk factors for discharge to PAC. Age (OR 1.05 [1.04 to 1.06], P < 0.001), partial (OR 2.86 [1.93 to 3.79], P < 0.001) or total dependence (OR 3.12 [1.45 to 4.79], P < 0.001) for activities of daily living, American Society of Anesthesiologist's classification (OR 1.27 [1.13 to 1.43], P < 0.001), dementia (OR 1.49 [1.28 to 1.74], P < 0.001), and total hospital length of stay (OR 1.10 [1.08 to 1.13], P < 0.001) were independent risk factors for prolonged PAC stay >30 days. DISCUSSION: Discharge to PAC is the norm among patients undergoing hip fracture surgery. Provider foreknowledge of risk factors may help improve hip fracture outcomes and decrease healthcare costs.

Newborn Sequencing in Genomic Medicine and Public Health.

The rapid development of genomic sequencing technologies has decreased the cost of genetic analysis to the extent that it seems plausible that genome-scale sequencing could have widespread availability in pediatric care. Genomic sequencing provides a powerful diagnostic modality for patients who manifest symptoms of monogenic disease and an opportunity to detect health conditions before their development. However, many technical, clinical, ethical, and societal challenges should be addressed before such technology is widely deployed in pediatric practice. This article provides an overview of the Newborn Sequencing in Genomic Medicine and Public Health Consortium, which is investigating the application of genome-scale sequencing in newborns for both diagnosis and screening.

¿Cuál fue el impacto de la pandemia por COVID-19 en neurocirugía? Análisis retrospectivo de 434 casos / What was the impact of the COVID-19 pandemic on neurosurgery? Retrospective analysis of 434 cases

Introducción: En 2020 se implementó globalmente una reducción de procedimientos neuroquirúrgicos "electivos" con el objetivo de redirigir recursos para la atención del creciente influjo de pacientes con COVID-19. Existe actualmente poca evidencia respecto al impacto que el COVID-19 y las reestructuraciones en la práctica tuvieron sobre los resultados en los pacientes neuroquirúrgicos. Objetivo: Comparar los resultados relacionados con las complicaciones postoperatorias, estado funcional de egreso, tasa de mortalidad hospitalaria (TMH) y días de hospitalización, entre pacientes operados antes y después del "aislamiento social, preventivo y obligatorio" (ASPO) por la pandemia por COVID-19 en un servicio de neurocirugía. Materiales y Métodos: Se realizó un estudio observacional, analítico y retrospectivo en el Servicio de Neurocirugía de nuestra institución en el período de dos años. Las variables fueron comparadas entre dos grupos de pacientes, grupo "PREPANDEMIA" y grupo "PANDEMIA" Resultados: Existió una disminución del 43% en el total de cirugías en 2020 respecto al año previo. Se observó diferencias significativas entre ambos grupos en los antecedentes oncológicos (14,91% vs. 22,44%, p 0,049), obesidad (34,2% vs 38,5%, p 0,023) y tabaquismo (6,2% vs 25,3%, p<0,001) complicaciones clínicas postoperatorias (13,09% vs 32,29%, p<0,000), estadía hospitalaria (p 0,04) y TMH (5,26% vs 12,1% p 0,021). Conclusión: La comparación de los resultados quirúrgicos evidenció un aumento significativo de las complicaciones clínicas, de la tasa de mortalidad hospitalaria postoperatoria y de la cantidad de días de hospitalización, sin diferencias significativas en el estado funcional al alta hospitalaria en los pacientes tratados durante la pandemia, respecto al año previo

Introduction: In 2020, it has been recommended to reduce elective neurosurgeries, with the aim of redirecting healthcare resources to the crescent incoming of COVID patients. There is currently little evidence regarding the impact that COVID-19 and restructuring in practice had on outcomes in neurosurgical patients. Objective: To compare the outcomes related to postoperative complications, performance status at discharge, the hospital mortality rate (HMR), and length of hospital stay (LoS), among patients operated before and after "social, preventive and compulsory isolation" (ASPO) due to the COVID-19 pandemic in a neurosurgery department. Materials and Methods: An observational, analytical, and retrospective study was carried out in the Neurosurgery Department of our institution over a period of two years. The variables were compared between two groups of patients, the "PREPANDEMIA" group and the "PANDEMIC" group. Results: There was a 43% reduction in the total procedures in 2020 compared to the previous year. Significant differences were observed between both groups in oncological history (14.91% vs. 22.44%, p. 0.049), obesity (34.2% vs. 38.5%, p. 0.023), tabaquism (6.2% vs. 25.3%, p <0.001), postoperative clinical complications (13.09% vs 32.29%, p <0.000), LoS (p 0.04) and HMR (5.26% vs 12.1% p 0.021). Conclusion: The comparison of surgical outcomes showed a significant increase in clinical complications, in the HMR and the LoS, without significant differences in the performance status at hospital discharge, in patients treated during the pandemic compared to the previous year.

Callosotomía posterior: un nuevo abordaje en Cirugía de Epilepsia / Posterior callosotomy: a new approach in Epilepsy Surgery

Objetivo: describir la nueva técnica de callosotomía posterior utilizada en cirugía de epilepsia, junto a sus indicaciones, ventajas comparativas y sus resultados. Métodos: se muestran en secuencias de video dos casos de callosotomía posterior, en pacientes con epilepsia refractaria severa, con crisis tipo "drop attacks" (pérdida súbita del tono postural), presentando traumatismos a repetición, con potencial riesgo de vida. Ambos pacientes, una mujer de 35 años y un varón de 24 años de edad, presentaban una malformación congénita del desarrollo cortical denominada doble corteza. Un caso fue operado en posición semisentada, con abordaje parafalcino derecho, el segundo en decúbito ventral, con abordaje parafalcino izquierdo. Se realizó una incisión vertical parasagital de 7cm, a 2 cm de la línea media, con límite inferior en el inion y superior en la unión de la sutura sagital y lambdoidea. Se realizó una craneotomía de 5 x 5cm, exponiendo el seno longitudinal superior. La anatomía venosa de la región permite sin inconvenientes el desplazamiento lateral occipito-parietal. Se realizó una callosotomía que incluyó esplenio y cuerpo llegando anteriormente al sector que une ambas áreas motoras suplementarias. Resultados: no se presentaron complicaciones postoperatorias. El síndrome de desconexión apareció en un caso, desapareciendo en un periodo de 2 semanas. Se obtuvo una reducción del 90% de crisis, mejorando la calidad de vida y otorgando un mayor grado de independencia a ambos pacientes. Conclusión: la callosotomía posterior es un procedimiento seguro, poco invasivo y altamente efectivo contra las crisis de drop attacks en epilepsias refractarias

Objective: to describe the new technique of posterior callosotomy applied to epilepsy surgery, including its indication, comparative advantages and results. Methods: two surgical cases are presented on video sequences, including patients with refractory epilepsy, with "drop attack" type seizures (loss of postural tone), presenting with recurring trauma and a potential life risk. Both patients, a 35 years-old woman and a 24 years-old man suffered from a congenital malformation of cortical development known as double cortex. One of the cases was operated in a semi-sitting position, trough a right parafalcine approach, and the other one in a prone position trough a left parafalcine approach. A 7cm parasagittal vertical incision, 2cm lateral to midline was performed, considering its upper limit at the union of the lambdoid and parasagittal suture, and its lower limit at the inion. A craniotomy of 4 by 4cm was performed, exposing the superior sagittal sinus. The venous regional anatomy allows an easy parieto-occipital lateral retraction. The callosotomy included the splenium and the body reaching anteriorly up to the region where we find both supplementary motor areas. Results: no postoperative complications were found. One case presented with a disconnection syndrome, resolving in 2 weeks. A 90% reduction of the seizure frequency was achieved, improving the quality of life and the degree of Independence of the patients. Conclusions: posterior callosotomy is a safe, less invasive and highly effective procedure against drop attack type seizures in refractory Epilepsy

Stimulation of dopamine D4 receptors in the paraventricular nucleus of the hypothalamus of male rats induces hyperphagia: involvement of glutamate.

Obesity is a serious worldwide health problem, affecting 20-40% of the population in several countries. According to animal models, obesity is related to changes in the expression of proteins that control energy homeostasis and in neurotransmission associated to regulation of food intake. For example, it has been reported that diet-induced obesity produces overexpression of dopamine D4 receptor (D4R) mRNA in the ventromedial hypothalamic nucleus (VMH) of mice. Neurons in the VMH send dense glutamatergic projections to other hypothalamic regions as the paraventricular nucleus (PVN), where multiple signals are integrated to finely regulate energy homeostasis and food intake. Although it is well established that dopaminergic transmission in the hypothalamus plays a key role in modulating feeding, the specific mechanisms involved in the activation of D4R in the PVN and its modulatory action on glutamate release and feeding behavior have remained unexplored. To fill this gap, we characterize the behavioral and neurochemical role of D4R in the PVN. In behavioral experiments, we examined the effects of activation of dopamine D4 receptors in the PVN on food intake and on the behavioral satiety sequence in rats exposed to a food-restricted feeding program. In vitro experiments were conducted to study the effects of activation of dopamine D4 receptors on [(3)H]glutamate release and on plasma corticosterone in explants of the PVN. We found that activation of D4R in the PVN induced inhibition of glutamate release and stimulated food intake by inhibiting satiety. Furthermore, activation of D4R in the PVN decreased plasma levels of corticosterone, and this effect was reverted by NMDA. According to our findings, D4R in the PVN may be a target for the pharmacotherapy for obesity as well as eating disorder patients who show restrictive patterns and overweight.

Sensitization of restraint-induced corticosterone secretion after chronic restraint in rats: involvement of 5-HT7 receptors.

Serotonin (5-HT) modulates the hypothalamic-pituitary-adrenal (HPA) axis response to stress. We examined the effect of chronic restraint stress (CRS; 20 min/day) as compared to control (CTRL) conditions for 14 days, on: 1) restraint-induced ACTH and corticosterone (CORT) secretion in rats pretreated with vehicle or SB-656104 (a 5-HT7 receptor antagonist); 2) 5-HT7 receptor-like immunoreactivity (5-HT7-LI) and protein in the hypothalamic paraventricular nucleus (PVN) and adrenal glands (AG); 3) baseline levels of 5-HT and 5-hydroxyindolacetic acid (5-HIAA), and 5-HIAA/5-HT ratio in PVN and AG; and 4) 5-HT-like immunoreactivity (5-HT-LI) in AG and tryptophan hydroxylase (TPH) protein in PVN and AG. On day 15, animals were subdivided into Treatment and No treatment groups. Treatment animals received an i.p. injection of vehicle or SB-656104; No Treatment animals received no injection. Sixty min later, Treatment animals were either decapitated with no further stress (0 min) or submitted to acute restraint (10, 30, 60 or 120 min); hormone serum levels were measured. No Treatment animals were employed for the rest of measurements. CRS decreased body weight gain and increased adrenal weight. In CTRL animals, acute restraint increased ACTH and CORT secretion in a time of restraint-dependent manner; both responses were inhibited by SB-656104. Exposure to CRS abolished ACTH but magnified CORT responses to restraint as compared to CTRL conditions; SB-656104 had no effect on ACTH levels but significantly inhibited sensitized CORT responses. In CTRL animals, 5-HT7-LI was detected in magnocellular and parvocellular subdivisions of PVN and sparsely in adrenal cortex. Exposure to CRS decreased 5-HT7-LI and protein in the PVN, but increased 5-HT7-LI in the adrenal cortex and protein in whole AG. Higher 5-HT and 5-HIAA levels were detected in PVN and AG from CRS animals but 5-HIAA/5-HT ratio increased in AG only. Finally, whereas 5-HT-LI was sparsely observed in the adrenal cortex of CTRL animals, it strongly increased in the adrenal cortex of CRS animals. No TPH protein was detected in AG from both animal groups. Results suggest that CRS promotes endocrine disruption involving decreased ACTH and sensitized CORT responses to acute restraint. This phenomenon may be associated with increased function and expression of 5-HT7 receptors as well as 5-HT turnover in AG.