Neurosurgical Institute Research Articles

Comorbid emotional disturbances in drug-resistant epilepsy in neurosurgical patients during the preoperative and postoperative periods

Background. Pharmacoresistant epilepsy, i.e. failure to achieve adequate seizure control with antiepileptic drugs develops in 30–40 % of patients. The surgical treatment for these patients are of particular importance. The relevance of studying the emotional sphere of neurosurgical patients with drug-resistant epilepsy stems from the high incidence of this pathology and its impact on patients’ quality of life.Objective. To investigate comorbidity indicators: depression and anxiety in neurosurgical patients with drug-resistant epilepsy during the preoperative and postoperative periods of epilepsy treatment.Design and methods. In 2019–2020, Polenov Neurosurgical Institute studied comorbid affective pathology in 46 neurosurgical patients with drug-resistant epilepsy in 2 groups: Group 1 — preoperative and Group 2 — postoperative patients, using HADS for screening.Results. The study included 46 patients in 2 groups. Group1 — 56.5 %, Group2 — 43.5 %. The mean age of the participants in the study was 30.8 ± 1.1 years. The sex ratio in the cohort was 1.7 males to 1 female. In the cohort, no anxiety was observed in 71.7 % and depression in 84.8 %, severe anxiety in 13 % and depression in 8.7 %.Conclusion. Among the neurosurgical patients with drug-resistant epilepsy, patients without symptoms of anxiety and depression predominated. There is a need to expand the sample and investigate further.

Seven bypasses simulation set: description and validity assessment of novel models for microneurosurgical training.

Microsurgical training remains indispensable to master cerebrovascular bypass procedures, but simulation models for training that accurately replicate microanastomosis in narrow, deep-operating corridors are lacking. Seven simulation bypass scenarios were developed that included head models in various surgical positions with premade approaches, simulating the restrictions of the surgical corridors and hand positions for microvascular bypass training. This study describes these models and assesses their validity. Simulation models were created using 3D printing of the skull with a designed craniotomy. Brain and external soft tissues were cast using a silicone molding technique from the clay-sculptured prototypes. The 7 simulation scenarios included: 1) temporal craniotomy for a superficial temporal artery (STA)-middle cerebral artery (MCA) bypass using the M4 branch of the MCA; 2) pterional craniotomy and transsylvian approach for STA-M2 bypass; 3) bifrontal craniotomy and interhemispheric approach for side-to-side bypass using the A3 branches of the anterior cerebral artery; 4) far lateral craniotomy and transcerebellomedullary approach for a posterior inferior cerebellar artery (PICA)-PICA bypass or 5) PICA reanastomosis; 6) orbitozygomatic craniotomy and transsylvian-subtemporal approach for a posterior cerebral artery bypass; and 7) extended retrosigmoid craniotomy and transcerebellopontine approach for an occipital artery-anterior inferior cerebellar artery bypass. Experienced neurosurgeons evaluated each model by practicing the aforementioned bypasses on the models. Face and content validities were assessed using the bypass participant survey. A workflow for model production was developed, and these models were used during microsurgical courses at 2 neurosurgical institutions. Each model is accompanied by a corresponding prototypical case and surgical video, creating a simulation scenario. Seven experienced cerebrovascular neurosurgeons practiced microvascular anastomoses on each of the models and completed surveys. They reported that actual anastomosis within a specific approach was well replicated by the models, and difficulty was comparable to that for real surgery, which confirms the face validity of the models. All experts stated that practice using these models may improve bypass technique, instrument handling, and surgical technique when applied to patients, confirming the content validity of the models. The 7 bypasses simulation set includes novel models that effectively simulate surgical scenarios of a bypass within distinct deep anatomical corridors, as well as hand and operator positions. These models use artificial materials, are reusable, and can be implemented for personal training and during microsurgical courses.

Is surgical resection predict overall survival in frail patients with glioblastoma, IDH-wildtype?

PurposeWe assessed the impact of frailty on surgical outcomes, survival, and functional dependency in elderly patients harboring a glioblastoma, isocitrate dehydrogenase (IDH)-wildtype. MethodsWe retrospectively reviewed records of old and frail patients surgical treated at a single neurosurgical institution between January 2018 to May 2021. Inclusion criteria were: (1) neuropathological diagnosis of glioblastoma, IDH-wildtype; (2) patient≥65years at the time of surgery; (3) available data to assess the frailty index according to the 5-modified Frailty Index (5-mFI). ResultsA total of 47 patients were included. The 5-mFI was at 0 in 11 cases (23.4%), at 1 in 30 cases (63.8%), at 2 in two cases (4.2%), at 3 in two cases (4.2%), and at 4 in two cases (4.2%). A gross total resection was performed in 26 patients (55.3%), a subtotal resection was performed in 13 patients (27.6%), and a biopsy was performed in 8 patients (17.1%). The rate of 30-day postoperative complications was higher in the biopsy subgroup and in the 5-mFI=4 subgroup. Gross total resection and age≤70years were independent predictors of a longer overall survival. Sex, 5-mFI, postoperative complications, and preoperative Karnofsky Performance Status score did not influence overall survival and functional dependency. ConclusionIn patients≥65years harboring a glioblastoma, IDH-wildtype, gross total resection remains an independent predictor of longer survival and good postoperative functional recovery. The frailty, assessed by the 5-mFI score, does not influence surgery and outcomes in this dataset. Further confirmatory analyses are required.

Role and mechanism of autophagy in the occurrence and development of meningothelial meningioma

This paper aims to investigate the role and mechanism of autophagy in meningioma. A total of 182 meningiomas which diagnosed in the ultrastructural pathology department of Beijing Neurosurgical Institute, Beijing Tiantan Hospital from 1993 to 2021. Light microscope, electron microscope, western blotting and immunohistochemical staining were used. 182 meningiomas, 104 males and 78 females. There were 174 WHO grade 1 benign meningiomas, including 62 meningothelial types, 39 fibrous type, 58 transitional types, 15 angiomatous types, 6 WHO grade 2 cases, including 4 clear cell types and 2 atypical types, 2 WHO grade 3 anaplastic types. Transmission electron microscopy (TEM) showed that the incidence of autophagosomes as a high expression in 27 cases, most of which were meningothelial meningiomas. Immunohistochemical markers EMA, PR, Vimentin, SSTR-2, Ki67, and CD34 were positively expressed in most of the tumors, GFAP, S-100, desmin, C-erbB-2 expression were negative. Western blotting was used to detect the up-regulated proteins of LC3, Beclin1, and down-regulated proteins of Bax, Caspase3, mTOR, PI3K, Akt, S6 and 4EBP1in meningothelial meningiomas compared with the none –meningothelial control group.Autophagy is induced by down-regulating PI3K/Akt/mTOR signaling pathway molecules in meningothelial meningiomas, which can inhibit tumor apoptosis and promote tumorigenesis.

Modern Neurosurgery — the Multidisciplinary Integration of Competences an Technologies

Modern neurosurgery is based on the complex integration of basic and applied neurosciences and technologies. A significant number of different diagnostic and therapeutic approaches are used to prolong a patients life and preserve its quality to the maximum. At the same time, neurosurgery is the only clinical discipline providing direct access to the living human brain. A large body of information on the nervous system state and pathology, routinely generated in neurosurgery, attract specialists from the related medical and biological sciences. Such close cooperation of physicians, biologists, chemists, physicists, mathematicians, engineers, and other specialists ensures rapid and continuous improvement of neurosurgical treatment. This article highlights the spectrum of technologies in modern neurosurgery, the research tasks facing this specialty, and briefly the activities of the National Medical Research Center for Neurosurgery named after academician N.N. Burdenko the leading neurosurgical institution of the Russian Federation in priority clinical and scientific areas.

Factors Affecting Long-Term Surgical Outcomes of Spinal Extramedullary Ependymomas: A Retrospective Study

Spinal intradural-extramedullary ependymomas (IEEs) most commonly affect the lumbosacral spine. Because of their neural axis dissemination and adherence to neural structures, managing IEEs is still a controversial neurosurgical challenge. The study aimed to investigate the potential prognostic factors that influence long-term surgical outcomes by evaluating consecutively operated patients with IEEs. During the study period, medical records of all diagnosed patients with spinal tumors were reviewed retrospectively. This study included all patients with consecutive IEEs who underwent surgical intervention in 3 neurosurgical institutions in different periods (February 2004 to December 2020). In 3 neurosurgical institutions, 64 (28 women, 36 men) patients were operated upon for IEE. The mean age of the patients at diagnosis was 38.9years. The mean preoperative symptom duration was 17.8months. Radicular pain was the most common symptom, observed in 53 patients. Gross total resection was applied to 48 patients. 54 patients had good clinical outcomes at their last follow-up after 106.9months on average. Myxopapillary ependymoma was the most common histopathological type (n= 43). The progression was observed in 5 patients. The presence of preoperative neurological deficits, IEEs extending >2 spinal levels, bone-eroded IEEs, surgical complication, capsule violation, and incomplete resection were associated with poor prognosis. Several clinical and surgical factors can affect the functional outcomes of the surgical treatment of IEEs. Some radiological features can make neurosurgeons aware of the prognosis of IEEs. In such cases, the neurosurgeons should plan to remove tumors without violating their integrities (capsules) to obtain satisfactory functional outcomes.

Variation of Superficial Temporal Artery-Middle Cerebral Artery(STA-MCA)Bypass

Superficial temporal artery-middle cerebral artery(STA-MCA)bypass surgery is a common operation in neurosurgery. There are several variations of this surgical method. We conducted a questionnaire survey on the details of surgical procedures in 171 neurosurgical institutes in Japan. Contrary to expectations, wide variations emerged in some surgical procedures, including the shape of skin and muscle incisions, the site of the temporary clip at the donor artery(STA), and the cutting method of the donor end. Western Japan institutions tended to vary more in terms of skin incision methods and donor cutting methods. It will likely be useful in the future to be aware of the numerous variations in surgical methods.

Historical accuracy: determination of the foundation date of the Institute – National Center for Neurosurgery

Study of the documents from 1928–2015 allowed to determine historically accurate date of foundation of the National Center for Neurosurgery. On this date, due to the initiative from N. N. Burdenko and V. V. Kramer and according to the Decree of the Small Council of the Peoples’ Commissars of the RSFSR, the first Moscow neurosurgical clinic under the State Roentgen Institute opened its doors. Note in the preserved operation journal of the clinic states that the first patient was operated on by N. N. Burdenko on February 15th, 1929. In the context of surgical facilities, the date of first surgery is considered the date of their opening.In 1932, the Scientific Research Neurosurgical Institute was established at the first neurosurgical clinic which in 2015 in accordance with the Decree of the Government of the Russian Federation was transformed into the N. N. Burdenko National Medical Research Center for Neurosurgery.

Efficacy of endovascular superselective chemoembolization with HepaSphere 50–100 μm microspheres saturated with cytostatic in stopping nosebleeds in patients with nasopharyngeal cancer

The OBJECTIVE was to show the effectiveness of a new method for stopping nosebleeds in patients with nasopharyngeal cancer using endovascular superselective chemoembolization of the tumor arterial bed with HepaSphere 50–100 μm microspheres saturated with the cytostatic doxorubicin.METHODS AND MATERIALS. The results of treatment of 94 patients who against the background of progressive growth of nasopharyngeal cancer and ongoing combined treatment in oncology centers experienced nosebleeds are presented. In all these patients, according to the results of examinations in cancer centers, no convincing source of nosebleeds was identified. In the conditions of Polenov Neurosurgical Institute, 94 patients underwent endovascular superselective chemoembolization of the vasculature of nasopharyngeal cancer. The embolizate was a mixture of HepaSphere 50–100 μm microspheres saturated with the cytostatic doxorubicin (50 mg). All patients were included in the study in the absence of contraindications and after signing a voluntary informed consent approved by the ethics committee. The selection of patients was carried out according to the following criteria: thorough morphological verification of the neoplasm; locally advanced process of III and IV stages (T2-4 N0-2M0); no history of other cancers; absence of individual hematogenous metastases; absence of competitive pathology in the stage of decompensation; age was over 18 years old. All patients underwent induction-simultaneous chemoradiotherapy (CRT) with the use of radiation therapy in the usual dose fractionation regimen.RESULTS. The hemostatic effect was achieved in all 94 patients due to sequential superselective chemoembolization of the vasculature of the tumor itself with embolizate, which was a mixture of HepaSphere 50–100 μm microspheres saturated with the cytostatic doxorubicin (50mg). In the future, nosebleeds in these patients did not occur. The main sources of nosebleeds were the following branches of the external carotid artery: in 46.2 % of cases – the maxillary artery, in 37.6 % – the ascending pharyngeal artery, in 8.6 % – the occipital artery, in 5.4 % – the artery of the carotid node, in 2.2 % – other branches of the external and internal carotid arteries on one side or on both sides.CONCLUSION. The method of endovascular superselective chemoembolization with doxorubicin of the vasculature of nasopharyngeal cancer complicated by nosebleeds developed and introduced into medical practice was the initial stage of the combined treatment of these neoplasms. A good hemostatic effect was achieved in all 94 patients.

Japanese Subarachnoid Aneurysm Trial of Neurosurgical Clipping versus Endovascular Coiling in 1863 Patients with Ruptured Intracranial Aneurysms.

This is a post hoc multivariate analysis of the modified World Federation of Neurosurgical Societies (WFNS) grading project, multicenter prospective observational study including 38 neurosurgical institutions across Japan. Japan Neurosurgical Society WFNS grading committee conducted a modified WFNS grading project as a nationwide prospective registry study. We investigate the clinical outcome of both surgical and endovascular interventions after aneurysmal subarachnoid hemorrhage (SAH) in Japan. A total of 792 patients received surgical intervention and 417 patients received endovascular treatment. Eight hundred patients were female, and 409 patients were male. The mean age was 61.5 ± 13.7 years. At 3 month follow-up, there was no statistically significant difference in good clinical outcome between surgical (68.2%) and endovascular (60.9%) group (odds ratio, 0.89; 95% confidence interval, 0.68-1.16; p = 0.381). Unfavorable outcome rate was 31.8% (238 patients) in the surgical group and 39.1% (154 patients) in the endovascular group. Male, elderly people, modified Rankin scale condition before onset, high-grade modified WFNS clinical grading scale, intracerebral hematoma, posttreatment normal pressure hydrocephalus, and neurological deficit due to symptomatic vasospasm were risk factors for the clinical outcome. Treatment modality was not a statistical factor for clinical outcomes. Surgical clipping has still a major role in the management of SAH in Japan. The present study was not a randomized controlled study, but clinical outcome is not influenced by treatment modalities.

Personalised treatment for epilepsy: gender-specific comorbid emotional disturbances in drug-resistant epilepsy in neurosurgical patients

Background. Because of the apparent frequency and impact on patients’ quality of life, it is important to investigate the emotional domain of neurosurgical patients with drug-resistant epilepsy. The objective of this study was to investigate gender-specific signs of depression and anxiety in neurosurgical patients with drug-resistant epilepsy.Design and methods. In 2019–2020, Polenov Neurosurgical Institute studied comorbid emotional disturbances in 46 neurosurgical patients with drug-resistant epilepsy in two gender groups: Group 1 — male patients and Group 2 — female patients, using HADS, GAD-7, and Beck’s Depression Inventory in-depth screening.Results. The mean age of participants in the study was 30.8 ± 7.1 years. The male-to-female ratio was 1.5 to 1. The disease lasted an average of 19.2 years, with a mean age of onset of 11.7 years. HADS: normal in 74 % and 61 % of cases, subclinical anxious/depressed in 10 % and 17 % of cases, and clinical anxious/depressed in 16 % and 22 % of cases, respectively. On the GAD-7 scale, 57 % and 50 % were minimally anxious, 25 % and 11 % mildly anxious, 7 % and 33 % moderately anxious and 11 % and 6 % severely anxious. On the Beck’s Depression Inventory, 50 % and 37 % had no depressive symptoms, 32 % and 26 % had mild depression, 7 % and 23 % had moderate depression, 7 % and 5 % had severe depression, and 4 % and 9 % had clinical depression. Personalisation of treatment approaches for patients with affective disorders is driven by two key points: the inclusion of medications with antidepressant and antianxiety effects in addition to AEDs, and consideration of the effect of a given AED on the emotional domain.Conclusion. Among neurosurgical patients with drug-resistant epilepsy, patients without symptoms of anxiety and depression predominate in both male and female patients. In the long-term course of drug-resistant epilepsy, the gender differences in the emotional range of patients flatten out. There is a need to expand the sample and further investigate gender characteristics of neurosurgical patients in order to personalise the treatment of drug-resistant epilepsy.

COT-18 Trends in Primary Brain Tumors in Kumamoto Prefecture with Declining Birthrate and Aging Population - Kumamoto Prefecture Brain Tumor Epidemiological Survey

Backgrounds: The demographic characteristics of Kumamoto Prefecture are that there is little population movement and the total population remains constant at about 1.8 million, but in recent years the birthrate is declining and the population is aging. We have been conducting the Kumamoto Prefecture Brain Tumor Epidemiological Survey since 1989 in cooperation with neurosurgical institutions in the prefecture. In this study, we examined whether recent demographic changes have affected the incidence of primary brain tumors (BT). Methods: Patients with primary BT were collected annually from 44 institutions in Kumamoto Prefecture (as of 2020), and the number of incidences per 100,000 population was calculated for each BT for each year, excluding patients living outside the prefecture and duplicate cases. Results: The total number of primary BT was 11441 (top 3: meningioma 40%, pituitary adenoma 17%, glioma 17%). Of 4261 men with primary BT, the top 3 were meningioma (27%), glioma (23.7%), and pituitary adenoma (18.4%)), and 7180 women (top 3: meningioma (47.7%), pituitary adenoma (16.2%), and glioma (12.9%)). The number of primary BT increased every year, and the incidence increased significantly when comparing 1989–2004 and 2005–2020 (13.6 vs. 25.0/100,000, p<0.000001). Typical brain tumors (meningioma, pituitary adenoma, glioma, schwannoma, malignant lymphoma) also increased year by year, especially asymptomatic meningioma. The median age of asymptomatic meningiomas was significantly higher than that of symptomatic meningiomas (69 vs. 65 years, p<0.0001). Gliomas increased significantly in the later stages compared with the early stages in children (0–14 years) and the elderly (65 years and older). Conclusion: Our results suggest that an increase in the number of BT such as glioblastoma, which are more common in the elderly, as well as an increase in the number of opportunities for intracranial examinations in the aging of the population may be responsible for the increased incidence of primary BT.

ITVT-03. Use of Functional MRI and DTI for Surgical Planning of Maximal Extent of Resection of CNS Tumors - A Single Neurosurgical Center’s Experience

Abstract Use of functional neuroimaging capabilities such as fMRI, DTI, MRP, MRS, AS-PET-CT, SPECT, and TMS as noninvasive tools to visualize intrinsic brain and spine morphology in relation to function have developed over the past 30 years. Amongst these imaging modalities, functional magnetic resonance imaging (fMRI) is of particular interest since it follows the physiological coupling between neuronal electrical activity and metabolic structural (cellular) activity as it relates to tissue vascularity and perfusion states. As an adjunct to this modality, MRI-based diffusion tensor imaging (DTI) allows further detailed radiographic assessment of fiber tracts in the brain in relationship to the surgical lesion of interest. In addition, combination of other imaging modalities including MR perfusion and intraoperative tools such as neuronavigation and direct cortical stimulation can help guide the extent of maximal safe resection. Herein we present a case series from our neurosurgical institution of primary intra-axial, extra-axial, supratentorial, and brainstem tumors resected using fMRI and DTI for presurgical planning allowing for maximal safe extent of resection and outcomes.

Static permeability assessment method to distinguish brain tumour recurrence from pseudoprogression

Abstract Aims It is common to have adjuvant chemo-radiotherapy after primary brain tumour resection. It is a known side effect that enhancing lesion could be seen in radiation territory after treatment, termed as pseudoprogression. It has been a difficult task to distinguish brain between tumour recurrence from pseudoprogression after radiotherapy. Timing of occurrence of these can overlap. It is important to distinguish the two as management is completely different. Early intervention in recurrence could improve survival time while pseudoprogression could be self-limiting. Surgical resection of pseudoprogression could be counter-productive. The radiological approach has been relying on multimodality investigation and close follow up. It has come to our institution notice that there is a new technique which could distinguish the two conditions efficiently. That's static permeability assessment method, also known as treatment response assessment maps (TRAMs). Our experience with it so far has been beneficial. Method This is a retrospective case series review of primary brain tumour treatment in our neurosurgical institution in 2020. Two high resolution 3D T1-weighted brain MRI images were acquired after a standard dose of gadolinium based contrast agent was injected. The first acquisition began five minutes after injection, and the second began 60 – 105 minutes post contrast injection. The TRAMs technique is based on image subtraction that is post processed after acquisition. The resultant subtracted image set was mapped to grey scale values, where voxels showing contrast clearance were light grey/white, and those showing contrast accumulation were dark grey/black. The zero value (i.e. no clearance or accumulation) was therefore mid-grey. Those with contrast clearance is associated with tumour recurrence. TRAMs images were compared to serial follow up imaging and histopathology results to determine the diagnostic accuracy of the technique. Results We have identified 21 patients in this period who had concern of either of pseudoprogression or tumour recurrence/progression. There were 6 females and 15 males, mean age 51. There were 14 glioblastoma multiforme (GBM), 5 astrocytoma, 1 oligodendroglioma and 1 post radiotherapy arteriovenous malformation. 17 cases were found to have clear cut recurrence, pseudoprogression or mixture of both in TRAMS. These findings are backed up by histology or repeated follow up scan. 4 cases were considered as equivocal. In retrospect, these cases have challenging interpretation due to poor case selection. TRAMs could distinguish high grade transformation as well as detecting recurrence. In some difficult cases, it is found that both pseudoprogression and recurrence could happen together. Conclusion TRAMs is a useful adjunct to the multimodalities of diagnostic techniques in tricky situation. This has provided an efficient and easy to use tool for radiologists to come up with the answer. We are the first independent centre to report on this technique. This is still early days and fine-tuning of its use is still undergoing. It is clear this has saved precious resources and has given patients more suitable care. We think it would be beneficial for us to share our experience with others and hope to get future collaboration with other centres.

Surgical treatment of facet syndrome in segmental instability of the lumbar spine

A clinical example shows a rare case of surgical treatment of facet syndrome, which is formed against the background of instability of the spinal motion segment of the spine at the L IV -L V level using the method of laser vaporization and denervation of the facet joints. The aim of the work is to consider the clinical and diagnostic indicators of facet syndrome and to assess the role of imaging research methods in the diagnosis of this syndrome. At the outpatient stage, with long-term persistent pain syndrome in the lumbar spine, non-stop conservative methods of treatment, the patient underwent survey radiography and MRI examination of this area in order to exclude a specific process (oncopathology, pathological fracture against the background of osteoporosis, spondylitis, etc.) Chronic pain syndrome with its ineffective conservative treatment leads to maladjustment of the psychoemotional and professional-labor state of the patient. Determining the source of pain impulses in the lumbar spine can be difficult, since pain can cause degenerative and pathological changes in various anatomical structures of the spine (intervertebral disc, facet joints, ligaments, muscles, etc.), which can form a clinical picture of pain syndrome with its various manifestations and symptoms, which do not always clearly determine the level and structure of the affected spine. In this connection, for the timely and correct determination of the diagnosis of all patients with chronic pain syndrome in the lumbar spine, it is necessary to be sent to specialized neurosurgical institutions, in which patients undergo a set of necessary medical and diagnostic procedures to determine the further management tactics and treatment algorithm for this category of patients.

Intraoperative seizures occurrence in cortical mapping of eloquent areas

The effect of structural epilepsy on the frequency of intraoperative convulsive seizures is assessed when mapping functionally significant areas of the cerebral cortex during resection of intracerebral neoplasms. The work is based on the analysis of the results of intraoperative neurophysiological studies at the Polenov Neurosurgical Institute. For the period 20192020 87 intraoperative mappings of eloquent cortex were carried out during resections of intracerebral neoplasms: 79 mappings of the motor cortex and 16 mappings of auditory-speech areas during operations with awakening. When mapping the motor zones of the cortex, the frequency of seizures was 5.1%, while mapping the auditory-speech zones with awakening 18.75%. The division of cases of intraoperative convulsive seizures into two groups: seizures arising from motor mapping and seizures associated with the mapping of auditory zones reflects differences in factors that affect the excitability of the cerebral cortex. In motor mapping, stimulation occurs against the background of general anesthesia, unlike waking operations. The intensity of stimulation in auditory mapping is higher than in motor mapping in motor mapping. Formally, the current used in motor mapping is significantly higher than in mapping auditory zones. In general, with the development of intraoperative convulsive seizures, the current intensity of cortical stimulation does not exceed the average values required to stimulate functionally significant cortical zones. The presence of epileptic syndrome in patients with intracerebral tumors cannot be considered as a predictor of intraoperative seizure development when performing motor mapping under general anesthesia as well as during surgery with awakening for mapping of motor or auditory verbal zones.

Genome-wide interrogation of transfer RNA-derived small RNAs in a mouse model of traumatic brain injury.

Transfer RNA (tRNA)-derived small RNAs (tsRNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that tsRNAs are involved in neurological disorders and play a role in the pathogenesis of neurodegenerative disease. However, whether tsRNAs are involved in traumatic brain injury-induced secondary injury remains poorly understood. In this study, a mouse controlled cortical impact model of traumatic brain injury was established, and integrated tsRNA and messenger RNA (mRNA) transcriptome sequencing were used. The results revealed that 103 tsRNAs were differentially expressed in the mouse model of traumatic brain injury at 72 hours, of which 56 tsRNAs were upregulated and 47 tsRNAs were downregulated. Based on microRNA-like seed matching and Pearson correlation analysis, 57 differentially expressed tsRNA-mRNA interaction pairs were identified, including 29 tsRNAs and 26 mRNAs. Moreover, Gene Ontology annotation of target genes revealed that the significantly enriched terms were primarily associated with inflammation and synaptic function. Collectively, our findings suggest that tsRNAs may be associated with traumatic brain injury-induced secondary brain injury, and are thus a potential therapeutic target for traumatic brain injury. The study was approved by the Beijing Neurosurgical Institute Animal Care and Use Committee (approval No. 20190411) on April 11, 2019.

Neurophysiological phenotypes of pharmacoresistant temporal lobe epilepsy

Patients with a drug-resistant form of epilepsy can be treated by neurosurgery through the destruction or separation of the epileptic focus. If the results of clinical, neuro-imaging and neurophysiological methods are discordant, then the localization of the epileptogenic zone is performed based on the results of long-term invasive monitoring of the bioelectrical activity of the cortex and deep structures of the brain. The aim of this work was the retrospective analysis of the results of invasive monitoring of the bioelectrical activity of the brain to clarify the mechanisms of the formation of patterns of interictal and ictal activity in structural epilepsy. The study included 35 patients (18 men, 17 women) with drug-resistant temporal lobe epilepsy, who were treated at the Polenov Neurosurgical Institute. The examination included video-EEG monitoring, long-term invasive monitoring of bioelectrical activity of the cortex, and deep brain structures. The patients were divided into two groups according to the type of surgical treatment: 1) micro-surgical resection of the epileptic focus, including the zone of structural changes (24 patients); 2) stereotactic destruction of the amygdala-hippocampal complex (6 patients). The follow-up of the outcomes of the surgical treatment took place over 2-3 years. Depending on the results of the surgical treatment, the patients were divided into two groups: 1) patients with a favorable outcome (Engel 1–2) — 15 patients and 2) patients with no positive dynamics and a relatively poor outcome (Engel 3–4) — 15 patients. The results obtained showed that the patterns of interictal and ictal activity in their totality determine the neurophysiology, i.e the phenotype of temporal lobe epilepsy, reflecting the interference of pathogenetic and sanogenetic mechanisms. The localization of the epileptogenic zone should be based on the cumulative assessment of interictal and ictal activity. The presence of more than one focus of interictal activity, the secondary spread of epileptiform activity from the primary focus, are prognostically unfavorable factors.

Awake surgery for lesions near eloquent brain under scalp block and clinical monitoring: experience of single center with limited resources

BackgroundSurgery of the brain tumors near eloquent areas carries the risk of either disabling neurological deficit or inadequate resection with bad prognosis in both situations. Awake surgery is the gold standard procedure for such lesions. However, it requires certain anesthetic drugs, advanced techniques, and trained teams that are not available in every neurosurgical institute. This work aims to evaluate safety, feasibility, and outcome of operating on patients with space occupying lesions near eloquent areas under scalp block being continuously examined by a neurologist through retrospective study of 20 cases with supratentorial lesions related to language or sensorimotor cortex.ResultsThere were 12 males and 8 females with mean age 36.8 years. Forty percent of patients were presented by motor weakness. Tumors were related to motor cortex in 11 patients and to language areas in 9 patients. Mean operative time was 210 min. Gross or near total resection was achieved in 15cases, four cases had subtotal resection and biopsy only was done in 1 case. Two patients suffered from intraoperative seizures and conversion to general anesthesia was required in one patient.ConclusionOperating on tumors near eloquent brain areas under scalp block and continuous neurological examination during tumor resection proved to be effective in early detection and prevention of permanent major deficits especially in the developing countries with limited resources.

Severe traumatic brain injury management in Tanzania: analysis of a prospective cohort.

Given the high burden of neurotrauma in low- and middle-income countries (LMICs), in this observational study, the authors evaluated the treatment and outcomes of patients with severe traumatic brain injury (TBI) accessing care at the national neurosurgical institute in Tanzania. A neurotrauma registry was established at Muhimbili Orthopaedic Institute, Dar-es-Salaam, and patients with severe TBI admitted within 24 hours of injury were included. Detailed emergency department and subsequent medical and surgical management of patients was recorded. Two-week mortality was measured and compared with estimates of predicted mortality computed with admission clinical variables using the Corticoid Randomisation After Significant Head Injury (CRASH) core model. In total, 462 patients (mean age 33.9 years) with severe TBI were enrolled over 4.5 years; 89% of patients were male. The mean time to arrival to the hospital after injury was 8 hours; 48.7% of patients had advanced airway management in the emergency department, 55% underwent cranial CT scanning, and 19.9% underwent surgical intervention. Tiered medical therapies for intracranial hypertension were used in less than 50% of patients. The observed 2-week mortality was 67%, which was 24% higher than expected based on the CRASH core model. The 2-week mortality from severe TBI at a tertiary referral center in Tanzania was 67%, which was significantly higher than the predicted estimates. The higher mortality was related to gaps in the continuum of care of patients with severe TBI, including cardiorespiratory monitoring, resuscitation, neuroimaging, and surgical rates, along with lower rates of utilization of available medical therapies. In ongoing work, the authors are attempting to identify reasons associated with the gaps in care to implement programmatic improvements. Capacity building by twinning provides an avenue for acquiring data to accurately estimate local needs and direct programmatic education and interventions to reduce excess in-hospital mortality from TBI.