Surgical treatment of brainstem cavernomas using diffusion tensor imaging and diffusion tensor tractography.

INTRODUCTION: The aims of this study were to assess the prognosis of patients after a single haemorrhage from the cavernoma, and also in the case of rehaemorrhage, and to determine the indications for surgical treatment of brainstem cavernomas. MATERIAL AND METHODS: The study included a group of 35 patients with brainstem cavernomas, 23 women and 12 men aged 27 to 57 years (mean age 38.4). Up to 2005, MRI perfusion-weighted imaging/diffusion-weighted imaging had been carried out in 13 surgically treated patients. From 2005 onwards, the other 22 patients also underwent MRI diffusion tensor imaging and diffusion tensor tractography (DTI/DTT). DTI/DTT assessed the course of long fibre tracts. The course of the corticospinal tract, medial lemniscus and transverse pontine tracts was entered into the neuronavigation system. The surgical approach and the safe entry zone were determined based on the DTI/DTT. RESULTS: Our study showed that rehaemorrhage from a cavernoma depends on its size and volume. However, it is not related to its location. Based on the modified Rankin scale, the results of treatment of our patients after the first haemorrhage were better compared to the assessment after another haemorrhage. Complete resection was performed in 32 cases (91%) and partial resection in the remaining three (9%). Two patients underwent another surgery after several years due to partial resection. One patient presented with another haemorrhage after three years. New deficits developed postoperatively. Already existing deficits were exacerbated, but gradually resolved. Symptoms of cerebellar dysfunction and cranial nerve injury (including respiratory disorders) were the most difficult to resolve. CONCLUSIONS: Patients with brainstem cavernomas should undergo surgical treatment after their first haemorrhage, especially in the case of a large cavernoma. DTI/DTT should be used to determine the trajectory to the cavernoma, particularly to the deep cavernoma, and to determine the safe entry zone. Total resection of the cavernoma should be performed even where this means that reoperation is required.

Wall shear stress gradient is independently associated with middle cerebral artery aneurysm development: a case-control CFD patient-specific study based on 77 patients.

BACKGROUND: Previously published computational fluid dynamics (CFD) studies regarding intracranial aneurysm (IA) formation present conflicting results. Our study analysed the involvement of the combination of high wall shear stress (WSS) and a positive WSS gradient (WSSG) in IA formation. METHODS: We designed a case-control study with a selection of 38 patients with an unruptured middle cerebral artery (MCA) aneurysm and 39 non-aneurysmal controls to determine the involvement of WSS, oscillatory shear index (OSI), the WSSG and its absolute value (absWSSG) in aneurysm formation based on patient-specific CFD simulations using velocity profiles obtained from transcranial colour-coded sonography. RESULTS: Among the analysed parameters, only the WSSG had significantly higher values compared to the controls (11.05 vs - 14.76 [Pa/mm], P = 0.020). The WSS, absWSSG and OSI values were not significantly different between the analysed groups. Logistic regression analysis identified WSS and WSSG as significant co-predictors for MCA aneurysm formation, but only the WSSG turned out to be a significant independent prognosticator (OR: 1.009; 95% CI: 1.001-1.017; P = 0.025). Significantly more patients (23/38) in the case group had haemodynamic regions of high WSS combined with a positive WSSG near the bifurcation apex, while in the control group, high WSS was usually accompanied by a negative WSSG (14/39). From the analysis of the ROC curve for WSSG, the area under the curve (AUC) was 0.654, with the optimal cut-off value -0.37 Pa/mm. The largest AUC was recognised for combined WSS and WSSG (AUC = 0.671). Our data confirmed that aneurysms tend to form near the bifurcation apices in regions of high WSS values accompanied by positive WSSG. CONCLUSIONS: The development of IAs is determined by an independent effect of haemodynamic factors. High WSS impacts MCA aneurysm formation, while a positive WSSG mainly promotes this process.

BEST Life-"Bringing ECMO Simulation To Life"-How Medical Simulation Improved a Regional ECMO Program.

The implemented "ECMO for Greater Poland" program takes full advantage of the ECMO (extracorporeal membrane oxygenation) perfusion therapy to promote health for 3.5 million inhabitants in the region. The predominant subjects of implementation are patients with hypothermia, with severe reversible respiratory failure (RRF), and treatment of other critical states leading to heart failure such as sudden cardiac arrest, cardiogenic shock or acute intoxication. Finally, it promotes donation after circulatory death (DCD) strategy in selected organ donor cases. ECMO enables recovery of organs' function after unsuccessful lifesaving treatment. Because this organizational model is complex and expensive, we use advanced high-fidelity medical simulation to prepare for real-life implementation. During the first four months, we performed scenarios mimicking "ECMO for DCD," "ECMO for ECPR (extended cardiopulmonary resuscitation)," "ECMO for RRF" and "ECMO in hypothermia." It helped to create algorithms for aforementioned program arms. In the following months, three ECMO courses for five departments in Poznan (capitol city of Greater Poland) were organized and standardized operating procedures for road ECMO transportation within Medical Emergency System were created. Soon after simulation program, 38 procedures with ECMO perfusion therapy including five road transportations on ECMO were performed. The Maastricht category II DCD procedures were done four times on real patients and in two cases double successful kidney transplantations were carried out for the first time in Poland. ECMO was applied in two patients with hypothermia, nine adult patients with heart failure, and five with RRF, for the first time in the region. In the pediatric group, ECMO was applied in four patients with RRF and 14 with heart failure after cardiac surgery procedures. Additionally, one child was treated successfully following 200 km-long road transport on ECMO. We achieved good and promising results especially in VV ECMO therapy. Simulation-based training enabled us to build a successful procedural chain, and to eliminate errors at the stage of identification, notification, transportation, and providing ECMO perfusion therapy. We discovered the important role of medical simulation, not only to test the medical professional's skills, but also to promote ECMO therapy in patients with critical/life-threatening states. Moreover, it also resulted in increase of the potential organ pool from DCD in the Greater Poland region.

Surgical treatment of adult patients with thalamic tumors with the aid of tractography, fMRI, transcranial electrical stimulation and direct electrical stimulation of the subcortical white matter.

The aim of investigation was to assess treatment outcomes in adult patients with thalamic tumors, operated on with the aid of tractography (DTI) and monitoring of motor evoked potentials (MEPs) generated due to transcranial electrical stimulation (TES) and direct electrical stimulation (DES) of the subcortical white matter. 38 subsequent patients with thalamic tumors were operated on using tractography (DTI)-integrated neuronavigation, transcranial electrical stimulation (TES) and direct electrical stimulation (DES). The volumetric method was used to calculate pre- and postoperative tumor volume. Total tumor resection (100%) was performed in 18 (47%) patients, subtotal in 9 (24%) (mean extent of resection -89.4%) and partial in 11 (29%) patients (mean extent of resection -77.18%). The mean extent of resection for all surgical patients was 86.5%. Two (5.2%) patients died postoperatively. Preoperative hemiparesis was present in 18 (47%) patients. Postoperative hemiparesis was observed in 11 (29%) patients of whom only in 5 (13%) new paresis was noted due to surgical intervention. In patients with hemiparesis significantly more frequently larger tumor volume was detected preoperatively. Low mean normal fractional anisotropy (nFA) values in the internal capsule were observed statistically significantly more frequently in patients with preoperative hemiparesis as compared to the internal capsule of the unaffected hemisphere. Transcranial electrical stimulation helps to predict postoperative paresis of extremities. Direct electrical stimulation is an effective tool for intraoperative localization of the internal capsule thus helping to avoid postoperative deficit. In patients with tumor grade I and II the median time to tumor progression was 36 months. In the case of patients with grades III and IV it was 14 months. The median survival time in patients with grades I and II it was 60 months. In patients with grades III and IV it was 18 months. Basing on our results, patients with glioma grade I/II according to WHO classification are the best candidates for surgical treatment of thalamic tumors. In this group of the patients more often resection is radical, median time to progression and survival time are longer than in patients with gliomas grade III and IV. Within a 7-year follow-up none of the patients with GI/GII grade glioma died.

Surgical treatment and prognosis of adult patients with brainstem gliomas.

The paper presents 47 adult patients who were surgically treated due to brainstem gliomas. Thirteen patients presented with contrast-enhancing Grades III and IV gliomas, according to the WHO classification, 13 patients with contrast-enhancing tumours originating from the glial cells (Grade I; WHO classification), 9 patients with diffuse gliomas, 5 patients with tectal brainstem gliomas and 7 patients with exophytic brainstem gliomas. During the surgical procedure, neuronavigation and the diffusion tensor tractography (DTI) of the corticospinal tract were used with the examination of motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs) with direct stimulation of the fundus of the fourth brain ventricle in order to define the localization of the nuclei of nerves VII, IX, X and XII. Cerebellar dysfunction, damage to cranial nerves and dysphagia were the most frequent postoperative sequelae which were also the most difficult to resolve. The Karnofsky score established preoperatively and the extent of tumour resection were the factors affecting the prognosis. The mean time of progression-free survival (14 months) and the mean survival time after surgery (20 months) were the shortest for malignant brainstem gliomas. In the group with tectal brainstem gliomas, no cases of progression were found and none of the patients died during the follow-up. Some patients were professionally active. Partial resection of diffuse brainstem gliomas did not prolong the mean survival above 5 years. However, some patients survived over 5 years in good condition.

Morphological, hemodynamic, and clinical independent risk factors for anterior communicating artery aneurysms.

BACKGROUND AND PURPOSE: The pathogenesis of cerebral aneurysms still raises some controversies. The aim of this study was to identify morphological, hemodynamic, and clinical independent risk factors for anterior communicating artery (ACoA) aneurysm development. METHODS: Computed tomography angiography and transcranial color-coded sonography were performed in 77 patients with a nonbleeding ACoA aneurysm and in 73 controls. Symmetry of A1 segments of the anterior cerebral arteries, angles between A1 and A2 segments, tortuosity, diameter, mean velocity (Vm), pulsatility index, and volume flow rate in both A1 segments were determined. Moreover, all study participants completed a survey on their medical history. Multivariate backward stepwise logistic regression analysis was performed to identify independent risk factors for ACoA aneurysm development. RESULTS: Smoking, hypertension, asymmetry of A1 segments, the angle between A1 and A2 segments, A1 segment diameter, Vm, pulsatility index, and volume flow rate turned out to be associated with the occurrence of ACoA aneurysms on univariate analysis. Multivariate analysis identified smoking (odds ratio, 2.036; 95% confidence interval, 1.277-3.245), asymmetry of A1 segments>40% (odds ratio, 2.524; 95% confidence interval, 1.275-4.996), pulsatility index (odds ratio, 0.004; 95% confidence interval, 0.000-0.124), and the angle between A1 and A2 segments≤100° (odds ratio, 4.665; 95% confidence interval, 2.247-9.687) as independent strong risk factors for ACoA aneurysm development. CONCLUSIONS: The risk of ACoA aneurysm formation is determined by several independent clinical, morphological, and hemodynamic factors. The strongest independent risk factors include smoking, asymmetry of A1 segments>40%, low blood flow pulsatility, and the angle between A1 and A2 segments≤100°.

The use of functional magnetic resonance imaging in reducing a risk of postoperative neurological deficits in the patients with brain tumour.

BACKGROUND AND PURPOSE: The purpose of the study was to compare the results of operative treatment of tumours located in the sensory-motor cortex guided with functional magnetic resonance imaging (fMRI) combined with the neuro-na-vigation system to the results of classical operative treatment. MATERIAL AND METHODS: The studied group comprised 28 pa-tients with a tumour located in the sensory-motor cortex area who underwent surgery guided with fMRI and the neuro-na-vigation system. A control group comprised 30 patients with the same clinical diagnosis, operated on without functional neuronavigation. RESULTS: The use of functional neuronavigation allowed for an 18% reduction in the intensity of neurological deficits after surgical treatment in patients from the studied group, compared to the subjects from the control group (p = 0.0001). In the patients with diagnosed high-grade glioma, improvement in the neurological condition in the studied group was 16% (p = 0.03). The initial neurological condition and the results of surgical treatment in patients with a tumour located less than 5 mm from the sensory-motor cortex, determined in fMRI examination, are worse than in patients with a tumour located more than 5 mm. CONCLUSIONS: In patients with a diagnosed brain tumour in the sensory-motor cortex who have neurological deficits, fMRI provides valuable imaging data on active areas. Tumour location of more than 5 mm from the fMRI active area of the sensory-motor cortex is connected with a considerably lower risk of postoperative neurological deficits. Removing a tumour in the sensory-motor cortex region, guided with fMRI and the neuronavigation system, considerably lowers the risk of postoperative development or exacerbation of neurological deficits.

Reoperations of patients with low-grade gliomas in eloquent or near eloquent brain areas.

BACKGROUND AND PURPOSE: Reoperations of patients with recurrent low-grade gliomas (LGG) are not always recommended due to a higher risk of neurological deficits when compared to initial surgery. The purpose of the present study was to evaluate surgical outcomes of patients operated on for recurrent LGG. MATERIAL AND METHODS: Sixteen patients who had surgery for recurrent LGG out of 68 LGG patients who underwent surgery at the Department of Neurosurgery in Sosnowiec, Poland between 2005 and 2011 were enrolled in the study. RESULTS: A large tumour volume prior to the initial surgery was the most significant parameter influencing LGG progression (96.6 cm³ vs. 47.9 cm3, p = 0.01). Increased incidence of epileptic seizures and decreased mental ability according to Karnofsky score were the most common symptoms associated with tumour recurrence. In the group of patients with malignant transformation, the relative cerebral blood volume (rCBV) was considerably increased (1.21 vs. 2.41, p < 0.01). No statistically significant difference was found in terms of the extent of resection between initial surgery and reoperation. Similarly, no significant difference was found in the number of patients with a permanent neurological deficit after initial surgery and reoperation. CONCLUSIONS: Reoperations of the patients with recurrent LGG are not burdened with a higher risk of neurological sequelae when compared to initial surgery. The extent of resection during the surgery for LGG recurrence is comparable to initial surgery. The increase of rCBV seems to be a significant biomarker that indicates malignant transformation.

Polyspikes and Rhythmic Polyspikes During Volatile Induction of General Anesthesia With Sevoflurane Result in Bispectral Index Variations.

BACKGROUND: Although electroencephalography (EEG)-based indices may show artifactual values, raw EEG signal is seldom used to monitor the depth of volatile induction of general anesthesia (VIGA). The current analysis aimed to identify whether bispectral index (BIS) variations reliably reflect the actual depth of general anesthesia during presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anesthesia. METHODS: Sixty patients receiving either VIGA with sevoflurane using increasing concentrations (group VIMA) or vital capacity (group VCRII) technique or intravenous single dose of propofol (group PROP) were included. Monitoring included facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, BIS, standard EEG, and hemodynamic parameters. RESULTS: In the PROP group no EPs were observed. During different stages of VIGA with sevoflurane in the VIMA and VCRII groups, presence of polyspikes and rhythmic polyspikes in patients' EEGs resulted in artifactual BIS values indicating a false awareness/wakefulness from anesthesia, despite no concomitant change of FiAA, FeAA, and MAC of sevoflurane. Periodic epileptiform discharges did not result in aberrant BIS values. CONCLUSION: Our results suggest that raw EEG correlate it with values of BIS, FiAA, FeAA, and MAC of sevoflurane during VIGA. It seems that because artifactual BIS values indicating false awareness/wakefulness as a result of presence of polyspikes and rhythmic polyspikes in patients' EEGs may be misleading to an anesthesiologist, leading to unintentional administration of toxic concentration of sevoflurane in ventilation gas.

[Partial transcondylar approach - analysis of the surgical technique in cadaver simulation]. / Dostep przezklykciowy czesciowy - analiza techniki operacyjnej na podstawie symulacji na zwlokach.

The aim of the study was to present consecutive stages of the partial transcondylar approach. Six simulations of the partial transcondylar approach were performed on non-fixed human cadavers without any known pathologies in the head and neck. The consecutive stages of the procedure were documented with photographs and diagrams. The starting point for the partial transcondylar approach is a posterior repositioning of the suboccipital segment of the vertebral artery. The approach is achieved by partial removal of the occipital condyle and lateral mass of the atlas as well as by suboccipital craniectomy. Elevation of the cerebellar hemisphere presents an important supplement of the approach. The partial transcondylar approach is a reproducible technique, which provides surgical penetration of the anterior part of the cranio-cervical junction and related regions. This approach is particularly useful in the treatment of intradural tumours localized ventrally to the medulla.

Meningiomas of the anterior portion of the craniovertebral junction: immediate and late outcome following surgical removal using a partial transcondylar approach.

BACKGROUND AND PURPOSE: The partial transcondylar approach (PTA) is an alternative to the suboccipital approach in the surgical treatment of meningiomas of the anterior portion of the craniovertebral junction (APCVJ). The purpose of this study is to present our results of treatment of these meningiomas using PTA. MATERIAL AND METHODS: Fourteen patients (11 women, 3 men) with meningioma of the APCVJ were included in the study. Neurological status of the patients was assessed before and after surgery as well as at the conclusion of the treatment. The approximate volume of the operated tumour, its relation to large blood vessels, cranial nerves and brainstem, along with its consistency and vascularisation were assessed. RESULTS: The symptom duration ranged from 1 to 36 months (median: 11 months). In 79% of patients, motor deficits of the extremities were predominant symptoms. Less frequent symptoms included headache, cervical pain and sensory deficits of cervical nerves C2 to C5. Approximate volume of the tumours ranged from 2.5 mL to 22.1 mL (mean: 11.7 mL). Gross total or subtotal resection was achieved in 86% of patients. The postoperative performance status improved in 57%, did not change in 36% and deteriorated in 7% of the patients. CONCLUSIONS: The PTA is a useful technique for removal of meningiomas expanding intradurally of the APCVJ without significant compression of the medulla. The results of treatment were good in most patients.

Biology, Physics and Genetics of Intracranial Aneurysm Formation: A Review.

Intracranial aneurysms (IAs) are persistent, localised dilatations of the arterial wall that are found in approximately 3% of the general population. The most severe complication of IAs is rupture, which results in devastating consequences such as subarachnoid haemorrhage and brain damage with serious neurological sequelae. Numerous studies have characterised the mechanisms underlying IA development and growth and identified a number of environmental modifiable (smoking, hypertension) and nonmodifiable risk factors (related to the histology of cerebral arteries and genetic factors) in its pathogenesis. Haemodynamic stress also likely plays a crucial role in the formation of IAs and is conditioned by the geometry and morphology of the vessel tree, but its role in the natural history of unruptured IAs remains poorly understood; it is believed that changes in blood flow might generate the haemodynamic forces that are responsible for damage to the vascular wall and vessel remodelling that lead to IA formation. This review summarises the most relevant data on the current theories on the formation of IAs, with particular emphasis on the roles of special conditions resulting from the microscopic anatomy of intracranial arteries, haemodynamic factors, bifurcation morphometry, inflammatory pathways, and the genetic factors involved in IA formation.

Preservation of the Hypoxic Transcriptome in Glioblastoma Patient-Derived Cell Lines Maintained at Lowered Oxygen Tension.

Despite numerous efforts aiming to characterise glioblastoma pathology (GBM) and discover new therapeutic strategies, GBM remains one of the most challenging tumours to treat. Here we propose the optimisation of in vitro culturing of GBM patient-derived cells, namely the establishment of GBM-derived cultures and their maintenance at oxygen tension mimicking oxygenation conditions occurring within the tumour. To globally analyse cell states, we performed the transcriptome analysis of GBM patient-derived cells kept as spheroids in serum-free conditions at the reduced oxygen tension (5% O2), cells cultured at atmospheric oxygen (20% O2), and parental tumour. Immune cells present in the tumour were depleted, resulting in the decreased expression of the immune system and inflammation-related genes. The expression of genes promoting cell proliferation and DNA repair was higher in GBM cell cultures when compared to the relevant tumour sample. However, lowering oxygen tension to 5% did not affect the proliferation rate and expression of cell cycle and DNA repair genes in GBM cell cultures. Culturing GBM cells at 5% oxygen was sufficient to increase the expression of specific stemness markers, particularly the PROM1 gene, without affecting neural cell differentiation markers. GBM spheroids cultured at 5% oxygen expressed higher levels of hypoxia-inducible genes, including those encoding glycolytic enzymes and pro-angiogenic factors. The genes up-regulated in cells cultured at 5% oxygen had higher expression in parental GBMs compared to that observed in 20% cell cultures, suggesting the preservation of the hypoxic component of GBM transcriptome at 5% oxygen and its loss in standard culture conditions. Evaluation of expression of those genes in The Cancer Genome Atlas dataset comprising samples of normal brain tissue, lower-grade gliomas and GBMs indicated the expression pattern of the indicated genes was specific for GBM. Moreover, GBM cells cultured at 5% oxygen were more resistant to temozolomide, the chemotherapeutic used in GBM therapy. The presented comparison of GBM cultures maintained at high and low oxygen tension together with analysis of tumour transcriptome indicates that lowering oxygen tension during cell culture may more allegedly reproduce tumour cell behaviour within GBM than standard culture conditions (e.g., atmospheric oxygen tension). Low oxygen culture conditions should be considered as a more appropriate model for further studies on glioblastoma pathology and therapy.

Mucocoele and mucopyocoele of the frontal sinus penetrating to the cranial cavity and the orbit.

BACKGROUND AND PURPOSE: Mucocoele of the paranasal sinuses falls within the scope of interest for neurosurgery when erosion of the sinus wall and the osseous structures of the skull base develops and the lesion extends towards the cranial cavity, the orbit, the cavernous sinus or the sella turcica. The pa-per aims to present the method of treatment of extensive mucocoele which is used in our clinic. MATERIAL AND METHODS: We treated 7 patients (2 women and 5 men; age range: 27-68 years). Mucopyocoele was diagnosed in two cases, and mucocoele in the other five. In 5 cases, extension of the mucocoele to the cranial cavity and the orbit or to the ethmoid sinus and the orbit was observed. In the remaining 2 cases, mucopyocoele extended to the ethmoid sinus, the sphenoid and maxillary sinuses, cranial cavity and the orbit. The purpose of surgery was to remove the mucocoele or the mucopyocoele and to prevent recurrence. RESULTS: The postoperative course in all 7 patients was uneventful. All symptoms gradually receded. No relapse was observed in any patient during a follow-up period that varied from 10 months to 8 years; nor did incidents of inflammation of collateral sinuses occur. CONCLUSIONS: The treatment of mucocoele or mucopyocoele of the frontal sinus penetrating to the cranial cavity and the orbit consists of the following stages: cranialization of the frontal sinus, complete resection of the mucosa, tight closing of the frontal-nasal duct, and separating the air space of the opened collateral nasal sinuses from the cranial cavity with a large pedicled periosteal flap.

[Approach to the jugular foramen and related structures - an analysis of the surgical technique based on cadaver simulation]. / Dostep do otworu szyjnego i jego otoczenia - analiza techniki operacyjnej w oparciu o symulacje na zwlokach.

This study presents consecutive stages of the approach to the jugular foramen and related structures. Eleven simulations of the approach were performed on non-fixed human cadavers without any known pathologies in the head and neck. The consecutive stages of the procedure were documented with photographs and schematic diagrams. The starting point for the discussed approach is removal of the mastoid and petrosal parts of the temporal bone, as well as the jugular process and the jugular tuberculum. It allows penetration of the jugular foramen from the back. Widening of the approach enables penetration of the jugular foramen from above and the front. Approach to the jugular foramen is a reproducible technique, which provides surgical penetration of this foramen and related structures. This approach is particularly useful in the surgical treatment of tumours expanding in the petrous pyramid, surroundings of the petrosal part of the internal carotid artery, cerebellopontine angle, subtemporal fossa and nervous-vascular bundle of the neck.

Early and long-term results of the treatment of jugular paragangliomas using different ranges of surgical approach.

BACKGROUND AND PURPOSE: The applied approach to the jugular foramen is a combination of the juxtacondylar approach with the subtemporal fossa approach type A. The purpose of this study is to present our results of treatment of jugular paragangliomas using the aforementioned approach. MATERIAL AND METHODS: Twenty-one patients (15 women, 6 men) with jugular paragangliomas were included in the study. The neurological status of the patients was assessed before and after surgery as well as at the conclusion of treatment. The approximate volume of the tumour, its relation to large blood vessels, cranial nerves and brainstem, as well as consistency and vascularity were also assessed. RESULTS: The duration of symptoms ranged from 3 to 74 months. In 86% of patients hearing loss was the predominant symptom. The less frequent symptoms included pulsatile tinnitus in the head, dysphagia and dizziness. Approximate volume of the tumours ranged from 2 to 109 cm3. A gross total resection was achieved in 71.5% of patients. The postoperative performance status improved in 38% of patients, did not change in 38% and deteriorated in 24% of patients. CONCLUSIONS: A proper selection of the range of the approach to jugular foramen paragangliomas based on their topography and volume reduces perioperative injury without negative consequences for the radicality of the resection.

Surgical treatment of insular tumours with tractography, functional magnetic resonance imaging, transcranial electrical stimulation and direct subcortical stimulation support.

BACKGROUND AND PURPOSE: Surgical treatment of insular tumours carries significant risks of limb paresis or speech disturbances due to their localization. The development of intraoperative neuromonitoring techniques that involve evoked motor potentials induced via both direct and transcranial cortical electrical stimulation as well as direct subcortical white matter stimulation, intraoperative application of preoperative tractography and functional magnetic resonance imaging (fMRI) in conjunction with neuronavigation resulted in significant reduction of postoperative disabilities that enabled widening of indications for surgical treatment. The aim of this study was to present the authors' own experience with surgical treatment of insular gliomas. MATERIAL AND METHODS: Our cohort comprises 30 patients with insular gliomas treated at the Department of Neurosurgery in Sosnowiec. Clinical symptoms included sensorimotor partial seizures in 86.6%; generalized seizures in 23.3%; persistent headaches in 16.6% and hemiparesis in 6.6%. All the patients were operated on with intraoperative neuromonitoring that included transcranial cortical stimulation, direct subcortical white matter stimulation as well as tractography and fMRI concurrently with neuronavigation. The analysis in-cluded postoperative neurological evaluation along with the assessment of the radicalism of resection evaluated based on postoperative MRI. RESULTS: Postoperatively, four patients had permanent hemiparesis (13.3%); importantly, two out of those patients had preoperative deficits (6.6%). Persistent speech disturbances were present in four patients (13.3%). Partial sensorimotor seizures were noted in two patients (6.6%). Seizures in the other patients receded. Intraoperative transcranial electrical stimulation as well as direct subcortical white matter stimulation along with tractography (DTI) and fMRI facilitated gross total resection of insular gliomas in 53.5%, subtotal in 13.3% and partial resection in 33.1%. CONCLUSIONS: Implementation of TES, direct subcortical white master stimulation, DTI and fMRI into the management protocol of the surgical treatment of insular tumours resulted in total and subtotal resections in 66% of cases with permanent motor disability in 6.6% of patients. Poor prognosis for independent living after surgery mainly affects patients with WHO grade III or IV.

Prophylactic use of dural tenting sutures in elective craniotomies in adults-is it necessary? A study protocol for a multicentre, investigator- and participant-blinded randomised, parallel-group, non-inferiority trial.

BACKGROUND: In the early days of neurosurgery, extradural haemorrhages (EDHs) contributed to a high mortality rate after craniotomies. Almost a century ago, Walter Dandy reported dural tenting sutures as an effective way to prevent postoperative EDH. Over time, his technique gained in popularity and significance to finally become a neurosurgical standard. Yet, several retrospective reports and one prospective report have questioned the ongoing need for dural tenting sutures. Dandy's explanation that the haemostasis observed under hypotensive conditions is deceiving and eventually causes EDH may be obsolete. Today, proper intra- and postoperative care, including maintenance of normovolemia and normotension and the use of modern haemostatic agents, may be sufficient for effective haemostasis. Thus, there is a fundamental need to evaluate the necessity of dural tenting sutures in a solid, unbiased, evidence-based manner. METHODS: This study is designed as a randomised, multicentre, double-blinded, controlled interventional trial with 1:1 allocation. About one half of the participants will undergo craniotomy without dural tenting sutures and will be considered an intervention group. The other half will undergo craniotomy with these sutures. Both groups will be followed clinically and radiologically. The primary outcome is reoperation due to extradural haematoma. Secondary outcomes aim to evaluate the impact of dural tenting sutures on mortality, readmission risk, postoperative headaches, size of extradural collection, cerebrospinal fluid leak risk and the presence of any new neurological deficit. The study protocol follows the SPIRIT 2013 statement. DISCUSSION: It is possible that many neurosurgeons around the globe are tenting the dura in elective craniotomies which brings no benefit and only extends the operation. Unfortunately, there is not enough data to support or reject this technique in modern neurosurgery. This is the first study that may produce strong, evidence-based recommendations on using dural tenting sutures. TRIAL REGISTRATION, ETHICS AND DISSEMINATION: The Bioethics Committee of the Medical University of Warsaw approved the study protocol (KB/106/2018). The trial is registered at http://www.clinicaltrials.gov ( NCT03658941 ) on September 6, 2018. The findings of this trial will be submitted to a peer-reviewed neurosurgical journal. Abstracts will be submitted to relevant national and international conferences. TRIAL STATUS: Protocol version and date: version 1.5, 14.01.2020 First recruitment: September 7, 2018 Estimated recruitment completion: September 1, 2021.

Comprehensive assessment of a nationwide simulation-based course for artificial life support.

BACKGROUND: Successful implementation of medical technologies applied in life-threatening conditions, including extracorporeal membrane oxygenation (ECMO) requires appropriate preparation and training of medical personnel. The pandemic has accelerated the creation of new ECMO centers and has highlighted continuous training in adapting to new pandemic standards. To reach high standards of patients' care, we created the first of its kind, National Education Centre for Artificial Life Support (NEC-ALS) in 40 million inhabitants' country in the Central and Eastern Europe (CEE). The role of the Center is to test and promote the novel or commonly used procedures as well as to develop staff skills on management of patients needing ECMO. METHOD: In 2020, nine approved and endorsed by ELSO courses of "Artificial Life Support with ECMO" were organized. Physicians participated in the three-day high-fidelity simulation-based training that was adapted to abide by the social distancing norms of the COVID-19 pandemic. Knowledge as well as crucial cognitive, behavioral and technical aspects (on a 5-point Likert scale) of management on ECMO were assessed before and after course completion. Moreover, the results of training in mechanical chest compression were also evaluated. RESULTS: There were 115 participants (60% men) predominantly in the age of 30-40 years. Majority of them (63%) were anesthesiologists or intensivists with more than 5-year clinical experience, but 54% had no previous ECMO experience. There was significant improvement after the course in all cognitive, behavioral, and technical self-assessments. Among aspects of management with ECMO that all increased significantly following the course, the most pronounced was related to the technical one (from approximately 1.0 to more 4.0 points). Knowledge scores significantly increased post-course from 11.4 ± SD to 13 ± SD (out of 15 points). The quality of manual chest compression relatively poor before course improved significantly after training. CONCLUSIONS: Our course confirmed that simulation as an educational approach is invaluable not only in training and testing of novel or commonly used procedures, skills upgrading, but also in practicing very rare cases. The implementation of the education program during COVID-19 pandemic may be helpful in founding specialized Advanced Life Support centers and teams including mobile ones. The dedicated R&D Innovation Ecosystem established in the "ECMO for Greater Poland" program, with developed National Education Center can play a crucial role in the knowledge and know-how transfer but future research is needed.

[Extended subtemporal approach to the subtemporal fossa and related structures - analysis of the surgical technique based on cadaver simulation]. / Dostep podskroniowy rozszerzony do dolu podskroniowego i jego otoczenia - analiza techniki operacyjnej na podstawie symulacji na zwlokach.

The aim of the study was to present consecutive stages of the extended subtemporal approach (ESA). Seven simulations of ESA were performed on non-fixed human cadavers without any known pathologies in the head and neck. The consecutive stages of the procedure were documented with photographs and schemes. The starting point for ESA is osteotomy of the zygomatic arch and craniectomy including the greater wing of the sphenoid bone. Dislocation or removal of subtemporal fossa contents allows one to penetrate its inside and related structures. Additional widening of inspection allows osteotomy of the condyloid process of the mandible. ESA is a reproducible technique which provides surgical penetration of the subtemporal fossa and related structures. This approach is particularly useful in the surgical treatment of tumours expanding in the orbit, maxillary sinus, pterygopalatine fossa, nasopharynx, sphenoid sinus, cavernous sinus, parapharyngeal space, retromandibular fossa and surroundings of the petrosal part of the internal carotid artery.