| 1. |
- Axelson, Hans, et al.
(författare)
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Continuous subcortical language mapping in awake glioma surgery
- 2022
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Ingår i: Frontiers in Oncology. - : Frontiers Media S.A.. - 2234-943X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Repetitive monopolar short-train stimulation (STS) delivered from a suction probe enables continuous mapping and distance assessment of corticospinal tracts during asleep glioma resection. In this study, we explored this stimulation technique in awake glioma surgery. Fourteen patients with glioma involving language-related tracts were prospectively included. Continuous (3-Hz) cathodal monopolar STS (five pulses, 250 Hz) was delivered via the tip of a suction probe throughout tumor resection while testing language performance. At 70 subcortical locations, surgery was paused to deliver STS in a steady suction probe position. Monopolar STS influence on language performance at different subcortical locations was separated into three groups. Group 1 represented locations where STS did not produce language disturbance. Groups 2 and 3 represented subcortical locations where STS produced language interference at different threshold intensities (>= 7.5 and <= 5 mA, respectively). For validation, bipolar Penfield stimulation (PS; 60 Hz for 3 s) was used as a "gold standard" comparison method to detect close proximity to language-related tracts and classified as positive or negative regarding language interference. There was no language interference from STS in 28 locations (Group 1), and PS was negative for all sites. In Group 2 (STS threshold >= 7.5 mA; median, 10 mA), there was language interference at 18 locations, and PS (median, 4 mA) was positive in only one location. In Group 3 (STS threshold <= 5 mA; median, 5 mA), there was language interference at 24 locations, and positive PS (median 4 mA) was significantly (p < 0.01) more common (15 out of 24 locations) compared with Groups 1 and 2. Despite the continuous stimulation throughout tumor resection, there were no seizures in any of the patients. In five patients, temporary current spread to the facial nerve was observed. We conclude that continuous subcortical STS is feasibly also in awake glioma surgery and that no language interference from STS or interference at >= 7.5 mA seems to indicate safe distance to language tracts as judged by PS comparisons. STS language interference at STS <= 5 mA was not consistently confirmed by PS, which needs to be addressed.
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| 2. |
- Basma, Jaafar, et al.
(författare)
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Minimizing Collateral Brain Injury Using a Protective Layer of Fibrin Glue : Technical Note
- 2015
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Ingår i: World Neurosurgery. - : Elsevier BV. - 1878-8750 .- 1878-8769. ; 84:6, s. 2030-2036
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Neurosurgical procedures expose the brain surface to a constant risk of collateral injury. We describe a technique where the brain surface is covered with a protective layer of fibrin glue and discuss its advantages. METHODS: A thin layer of fibrin glue was applied on the brain surface after its exposure in 34 patients who underwent different craniotomies for tumoral and vascular lesions. Data of 35 more patients who underwent standard microsurgical technique were collected as a control group. Cortical and pial injuries were evaluated using an intra-operative visual scale. Eventual abnormal signals at the early postoperative T2-weighted fluid-attenuated inversion recovery (T2FLAIR) magnetic resonance imaging (MRI) sequences were evaluated in oncological patients. RESULTS: Total pial injury was noted in 63% of cases where fibrin glue was not used. In cases where fibrin glue was applied, a significantly lower percentage of 26% (P < 0.01) had pial injuries. Only 9% had injuries in areas covered with fibrin glue (P < 0.0001). Early postoperative T2FLAIR MRI confirmed the differences of altered signal around the surgical field in the two populations. CONCLUSION: We propose beside an appropriate and careful microsurgical technique the possible use of fibrin glue as alternative, safe, and helpful protection during complex microsurgical dissections. Its intrinsic features allow the neurosurgeon to minimize the cortical manipulation preventing minor collateral brain injury.
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| 3. |
- Basma, Jaafar, et al.
(författare)
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Mobilization of the Transcavernous Oculomotor Nerve During Basilar Aneurysm Surgery : Biomechanical Bases for Better Outcome
- 2014
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Ingår i: Neurosurgery. - 0148-396X .- 1524-4040. ; 10:1, s. 106-114
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The transcavernous approach adds a significant exposure advantage in basilar aneurysm surgery. However, one of its frequently reported side effects is postoperative oculomotor nerve palsy. OBJECTIVE: To present the technique of mobilizing the oculomotor nerve throughout its intracranial course and to analyze its consequences on the nerve tension and clinical outcome. METHODS: The oculomotor nerve is mobilized from its mesencephalic origin to the superior orbital fissure. Its degree of mobility, related to the imposed pulling force, was measured in 11 cadaveric nerves. Tension was mathematically deduced and compared before and after mobilizing of the cavernous segment. One hundred four patients treated for basilar aneurysms with the orbitozygomatic pretemporal transcavernous approach were followed up for a 1-year period and evaluated for postoperative oculomotor nerve palsy. RESULTS: Releasing the transcavernous segment compared to cisternal mobilization alone resulted in a significant increase in freedom of mobility from 4 to 7.9 mm (P < .001) and in a significant decrease in tension from 0.8 to 0.5 N (P = .006). Ninety-nine percent of aneurysms treated with this technique were amenable to neck clipping, and a total of 84% of patients had a good postoperative outcome (modified Rankin Scale score, 0-2). All patients showed direct postoperative palsy; however, 97% had a complete recovery by 9 months. Only 3 patients had a persistent diplopia on medial gaze, which was corrected with prism glasses. CONCLUSION: Mobilization of the transcavernous oculomotor nerve results in better maneuverability and less tension on the nerve, which lead to successful surgical treatment and favorable oculomotor outcome.
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| 4. |
- Borota, Ljubisa, et al.
(författare)
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Complete functional recovery in a child after endovascular treatment of basilar artery occlusion caused by spontaneous dissection : a case report
- 2022
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Ingår i: Child's Nervous System. - : Springer Nature. - 0256-7040 .- 1433-0350. ; 38:8, s. 1605-1612
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Tidskriftsartikel (refereegranskat)abstract
- Stroke caused by dissection of arteries of the vertebrobasilar system in children is still poorly investigated in terms of etiology, means of treatment, course of disease, and prognosis. The aim of this report was to describe the unusual course of a spontaneous dissection of the basilar artery (BA) in a child treated with endovascular techniques and to point out that the plasticity of the brain stem can fully compensate for structural damage caused by stroke. We report the case of a 15-year-old boy who suffered a wake-up stroke with BA occlusion caused by spontaneous dissection. A blood clot was aspirated from the false lumen and the true lumen re-opened, but the patient deteriorated a few hours later, and repeated angiography revealed that the intimal flap was detached, occluding the BA again. The lumen of BA was then reconstructed by a stent. Despite a large pons infarction, the patient was completely recovered 11 months after the onset. The case was analyzed with angiograms and magnetic resonance imaging, macroscopic and microscopic pathological analysis, computed tomographic angiography, magnetic resonance-based angiography, and diffusion tensor imaging. This case illustrates that applied endovascular techniques and intensive care measures can alter the course of potentially fatal brain stem infarction. Our multimodal analysis gives new insight into the anatomical basis for the plasticity mechanism of the brain stem.
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| 5. |
- Engström, Maria, et al.
(författare)
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Neuroimaging in the Kleine-Levin Syndrome
- 2018
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Ingår i: Current Neurology and Neuroscience Reports. - Philadelphia, United States : Springer Science and Business Media LLC. - 1528-4042 .- 1534-6293. ; 18:9
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Forskningsöversikt (refereegranskat)abstract
- PURPOSE OF REVIEW: The purpose was to review the most recent literature on neuroimaging in the Kleine-Levin syndrome (KLS). We aimed to investigate if frontotemporal and thalamic dysfunction are key KLS signatures, and if recent research indicates other brain networks of interest that elucidate KLS symptomatology and aetiology.RECENT FINDINGS: In a comprehensive literature search, we found 12 original articles published 2013-2018. Most studies report deviations related to cerebral perfusion, glucose metabolism, or blood-oxygen-level-dependent responses in frontotemporal areas and/or the thalamus. Studies also report dysfunction in the temporoparietal junction and the oculomotor network that also were related to clinical parameters. We discuss these findings based on recent research on thalamocortical networks and brain stem white matter tracts. The hypothesis of frontotemporal and thalamic involvement in KLS was confirmed, and additional findings in the temporoparietal junction and the oculomotor system suggest a broader network involvement, which can be investigated by future high-resolution and multimodal imaging.
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| 6. |
- Fahlström, Markus, et al.
(författare)
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Qualitative and Visual Along-Tract Analysis of Diffusion-Based Parameters in Patients with Diffuse Gliomas
- 2024
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Ingår i: Brain Sciences. - : MDPI. - 2076-3425. ; 14:3
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Tidskriftsartikel (refereegranskat)abstract
- Background: Grade 2-3 diffuse gliomas (DGs) show extensive infiltration through white matter (WM) tracts. Along-tract analysis of WM tracts based on diffusion tensor tractography (DTI) can been performed to assess the microstructural integrity of WM tracts. The clinical implication of these DTI-related findings is still under debate, especially in tumor patients. The aim of this study was to analyze and compare diffusion-based parameters along WM tracts and variables specific to WM -tumor interactions in DGs and correlate them with preoperative neuropsychological assessment.Methods: Fourteen patients with IDH-mutated grade 2-3 DGs were included. Tumor volumes were manually segmented on 3D-FLAIR images after spatial normalisation to MNI space. DTI was acquired using a single-shot echo-planar sequence on a 3T with 48 sampling directions. DTI data were reconstructed within the MNI space using q-space diffeomorphic reconstruction (QSDR) in DSI studio. Five bilateral sets of WM tracts were reconstructed based on the HCP-1065 template. All WM tracts were stretched to the same length of 100 indices, and for each index diffusion-based parameters fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD), mean diffusivity (MD) and quantitative anisotropy (QA) were sampled. Tumor-related parameters (TRP); tumor volume (Tv), maximum tumor presence (MTP) and the number of sequential indices in which a tumor is present (Te) were derived based on the along-tract analysis. Normal data were constructed by calculating the average and standard deviations of contralateral and not-affected WM tracts for each diffusion-based parameter, respectively. Affected WM tracts were individually compared to normal data using a z-test. Preoperative neuropsychological assessment was performed in all subjects and correlated to results from the along-tract analysis using correlation and logistic regression models.Results: Abnormalities in diffusion-based parameters were detected in WM tracts. Topographical and quantitative information were presented within the same graph. AD and MD displayed the highest linear correlation with the TRPs. Abnormal QA showed a linear correlation with Tv per WM tract. Neuropsychological impairment was correlated with all the TRPs and with abnormal FA (p < 0.05) and abnormal QA (p < 0.01). Abnormal QA was the only independent variable able to predict the presence of neuropsychological impairment in the patients based on the linear regression analysis.Conclusions: Graphical presentation of the along-tract analysis presented in this study shows that it may be a sensitive and robust method to acquire and display topographical and qualitative information regarding WM tracts in close proximity to DGs. Further studies and refinements to the methods presented herein may advance current clinical methods for evaluating displacement and infiltrations and further aid the efforts of pre-planning surgical interventions with the goal to maximise EOR and tailor oncological treatment.
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| 7. |
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| 8. |
- Falk Delgado, Anna, et al.
(författare)
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Preoperative Quantitative MR Tractography Compared with Visual Tract Evaluation in Patients with Neuropathologically Confirmed Gliomas Grades II and III : A Prospective Cohort Study
- 2016
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Ingår i: Radiology research and practice. - : Hindawi Limited. - 2090-1941 .- 2090-195X. ; 2016:1, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose. Low-grade gliomas show infiltrative growth in white matter tracts. Diffusion tensor tractography can noninvasively assess white matter tracts. The aim was to preoperatively assess tumor growth in white matter tracts using quantitative MR tractography (3T). The hypothesis was that suspected infiltrated tracts would have altered diffusional properties in infiltrated tract segments compared to noninfiltrated tracts. Materials and Methods. Forty-eight patients with suspected low-grade glioma were included after written informed consent and underwent preoperative diffusion tensor imaging in this prospective review-board approved study. Major white matter tracts in both hemispheres were tracked, segmented, and visually assessed for tumor involvement in thirty-four patients with gliomas grade II or III (astrocytomas or oligodendrogliomas) on postoperative neuropathological evaluation. Relative fractional anisotropy (rFA) and mean diffusivity (rMD) in tract segments were calculated and compared with visual evaluation and neuropathological diagnosis. Results. Tract segment infiltration on visual evaluation was associated with a lower rFA and high rMD in a majority of evaluated tract segments (89% and 78%, resp.). Grade II and grade III gliomas had similar infiltrating behavior. Conclusion. Quantitative MR tractography corresponds to visual evaluation of suspected tract infiltration. It may be useful for an objective preoperative evaluation of tract segment involvement.
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| 9. |
- Hossain, Iftakher, et al.
(författare)
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Huge variability in restrictions of mobilization for patients with aneurysmal subarachnoid hemorrhage - A European survey of practice
- 2023
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Ingår i: BRAIN AND SPINE. - : Elsevier. - 2772-5294. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: One of the major goals of neurointensive care is to prevent secondary injuries following aSAH. Bed rest and patient immobilization are practiced in order to decrease the risk of DCI.Research question: To explore the current practices in place concerning the management of patients with aSAH, specifically, protocols and habits regarding restrictions of mobilization and HOB positioning.Material and methods: A survey was designed, modified, and approved by the panel of the Trauma & Critical Care section of the EANS to cover the practice of restrictions of patient mobilization and HOB positioning in patients with aSAH.Results: Twenty-nine physicians from 17 countries completed the questionnaire. The majority (79.3%) stated that non-secured aneurysm and the presence of an EVD were the factors related to the establishment of restriction of mobilization. The average duration of the restriction varied widely ranging between 1 and 21 days. The presence of an EVD (13.8%) was found to be the main reason to recommend restriction of HOB elevation. The average duration of restriction of HOB positioning ranged between 3 and 14 days. Rebleeding or complications related to CSF over-drainage were found to be related to these restrictions.Discussion and conclusion: Restriction of patient mobilization regimens vary widely in Europe. Current limited evidence does not support an increased risk of DCI rather the early mobilization might be beneficial. Large prospective studies and/or the initiative of a RCT are needed to understand the significance of early mobilization on the outcome of patients with aSAH.
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| 10. |
- Latini, Francesco, 1982-, et al.
(författare)
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A novel radiological classification system for cerebral gliomas: The Brain-Grid.
- 2019
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Standard radiological/topographical classifications of gliomas often do not reflect the real extension of the tumor within the lobar-cortical anatomy. Furthermore, these systems do not provide information on the relationship between tumor growth and the subcortical white matter architecture. We propose the use of an anatomically standardized grid system (the Brain-Grid) to merge serial morphological magnetic resonance imaging (MRI) scans with a representative tractographic atlas. Two illustrative cases are presented to show the potential advantages of this classification system.MRI scans of 39 patients (WHO grade II and III gliomas) were analyzed with a standardized grid created by intersecting longitudinal lines on the axial, sagittal, and coronal planes. The anatomical landmarks were chosen from an average brain, spatially normalized to the Montreal Neurological Institute (MNI) space and the Talairach space. Major white matter pathways were reconstructed with a deterministic tracking algorithm on a reference atlas and analyzed using the Brain-Grid system.In all, 48 brain grid voxels (areas defined by 3 coordinates, axial (A), coronal (C), sagittal (S) and numbers from 1 to 4) were delineated in each MRI sequence and on the tractographic atlas. The number of grid voxels infiltrated was consistent, also in the MNI space. The sub-cortical insula/basal ganglia (A3-C2-S2) and the fronto-insular region (A3-C2-S1) were most frequently involved. The inferior fronto-occipital fasciculus, anterior thalamic radiation, uncinate fasciculus, and external capsule were the most frequently associated pathways in both hemispheres.The Brain-Grid based classification system provides an accurate observational tool in all patients with suspected gliomas, based on the comparison of grid voxels on a morphological MRI and segmented white matter atlas. Important biological information on tumor kinetics including extension, speed, and preferential direction of progression can be observed and even predicted with this system. This novel classification can easily be applied to both prospective and retrospective cohorts of patients and increase our comprehension of glioma behavior.
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