82 results on '"Samandouras G"'
Search Results
2. Amyloid in neurosurgical and neurological practice
- Author
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Samandouras, G., Teddy, P.J., Cadoux-Hudson, T., and Ansorge, O.
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- 2006
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3. Neurosurgical Treatment of Nelson’s Syndrome
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Kelly, P A., Samandouras, G, Grossman, A B., Afshar, F, Besser, G M., and Jenkins, P J.
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- 2002
4. P.122Feasibility open label trial shows no effect of sodium valproate for McArdle disease
- Author
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Scalco, R., primary, Stemmerik, M., additional, Løkken, N., additional, Vissing, C., additional, Madsen, K., additional, Michalak, Z., additional, Godfrey, R., additional, Pattni, J., additional, Holton, J., additional, Samandouras, G., additional, Bassett, P., additional, Haller, R., additional, Vissing, J., additional, and Quinlivan, R., additional
- Published
- 2019
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5. PO75A STANDARDISED ANATOMICAL AND FUNCTIONAL CLASSIFICATION OF CORTICAL AND SUBCORTICAL BRAIN FUNCTION FOR INTRAOPERATIVE MAPPING DURING AWAKE CRANIOTOMY
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Ekanayake, J., primary and Samandouras, G., additional
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- 2015
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6. PO57SAFETY AND EFFICACY OF PREOPERATIVE CORTICAL MAPPING USING A NAVIGATED TRANSCRANIAL MAGNETIC STIMULATION (NTMS) TECHNOLOGY IN PATIENTS HARBORING BRAIN TUMOURS IN ELOQUENT AREAS
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Ekanayake, J., primary and Samandouras, G., additional
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- 2015
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7. Sodium valproate for McArdle disease (glycogen storage disease type V – GSDV)
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Scalco, R., primary, Vissing, C., additional, Godfrey, R., additional, Chatfield, S., additional, Løkken, N., additional, Madsen, K., additional, Pattni, J., additional, Michalak, Z., additional, Sewry, C., additional, Fox, Z., additional, McKenna, G., additional, Samandouras, G., additional, Holton, J., additional, Howell, J., additional, Haller, R., additional, Vissing, J., additional, and Quinlivan, R., additional
- Published
- 2015
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8. Holes in the brain: question
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Warner, E., primary, Jassar, B.S., additional, and Samandouras, G., additional
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- 2015
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9. Holes in the brain: answer
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Warner, E., primary, Jassar, B., additional, and Samandouras, G., additional
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- 2015
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10. Intraoperative, imaging and pathological features in spinal cord vasculitis
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Rourke, T., Hamidian, Jahromi A., Pretorius, P., Morris, J., Samandouras, G., and Cudlip, S.
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- 2009
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11. LB0002 Safety and Tolerability of Arimoclomol in Patients with Sporadic Inclusion Body Myositis: A Randomised, Double-Blind, Placebo-Controlled, Phase IIa Proof-of-Concept Trial
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Machado, P., primary, Miller, A., additional, Herbelin, L., additional, He, J., additional, Noel, J., additional, Wang, Y., additional, McVey, A. L., additional, Pasnoor, M., additional, Gallagher, P., additional, Statland, J., additional, Brady, S., additional, Lu, C.-H., additional, Kalmar, B., additional, Sethi, H., additional, Samandouras, G., additional, Holton, J., additional, Greensmith, L., additional, Barohn, R. J., additional, Hanna, M. G., additional, and Dimachkie, M. M., additional
- Published
- 2013
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12. G.P.117 - Sodium valproate for McArdle disease (glycogen storage disease type V – GSDV)
- Author
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Scalco, R., Vissing, C., Godfrey, R., Chatfield, S., Løkken, N., Madsen, K., Pattni, J., Michalak, Z., Sewry, C., Fox, Z., McKenna, G., Samandouras, G., Holton, J., Howell, J., Haller, R., Vissing, J., and Quinlivan, R.
- Published
- 2015
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13. An unusual cerebellar cyst
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Borg, A., primary, Samandouras, G., additional, Phadke, R., additional, and Kitchen, N., additional
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- 2010
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14. Schistosoma haematobium presenting as an intrinsic conus tumor
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Samandouras, G., primary, King, A., additional, and Kellerman, A. J., additional
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- 2002
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15. Life-threatening intra-abdominal haemorrhage following insertion of a lumboperitoneal shunt
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Samandouras, G., primary, Wadley, J., additional, and Afshar, F., additional
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- 2002
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16. Are recurrent epidermoid tumours ever curable? MRI and intraoperative findings
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Samandouras, G., primary and Aspoas, A. R., additional
- Published
- 2001
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17. Spinal cord infarction caused by malignant intramedullary glioma: the traps of epidemiology and travel history.
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Lawson-smith, M., Samandouras, G., Hinks, T., Tan, P. L., Quaghebeur, G., Mathews, P., Anosgore, O., and Aziz, T. Z.
- Subjects
- *
SPINAL cord diseases , *GLIOMAS , *TUMORS , *EDEMA , *HISTOLOGY , *INFARCTION - Abstract
This article presents a case report involving spinal cord infarction caused by malignant intramedullary glioma. A 19-year-old patient of Pakistani origin presented with paraplegia and a sensory level at T4. The patient was well until 3 weeks prior to his admission when he developed back and left leg pain. At the centre of the lesion a necrotic core was evident, while the spinal cord rostrally demonstrated extensive associated oedema. In the case reported, the diagnosis of intramedullary malignant glioma was not considered mainly because of its rarity, but also of the patients' ethnic background and his recent travel history. Intramedullary malignant gliomas are extremely rare representing less than 1.5% of spinal cord tumours.
- Published
- 2004
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18. Handling Severe Intraoperative Hemorrhage and Avoiding Iatrogenic Stroke During Brain Tumor Surgery: Techniques for Prevention of Hemorrhagic and Ischemic Complications.
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Ghare A, Wong QH, Sefcikova V, Waraich M, and Samandouras G
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- Humans, Arteries, Blood Loss, Surgical prevention & control, Iatrogenic Disease prevention & control, Intraoperative Complications etiology, Intraoperative Complications prevention & control, Intraoperative Complications epidemiology, Stroke prevention & control, Stroke complications, Brain Neoplasms surgery, Brain Neoplasms complications
- Abstract
Background: Nationwide databases show that iatrogenic stroke and postoperative hematoma are among the commonest complications in brain tumor surgery, with a 10-year incidence of 16.3/1000 and 10.3/1000, respectively. However, techniques for handling severe intraoperative hemorrhage and dissecting, preserving, or selectively obliterating vessels traversing the tumor are sparse in the literature., Methods: Records of the senior author's intraoperative techniques during severe haemorrhage and vessel preservation were reviewed and analyzed. Intraoperative media demonstrations of key techniques were collected and edited. In parallel, a literature search investigating technique description in handling severe intraoperative hemorrhage and vessel preservation in tumor surgery was undertaken. Histologic, anesthetic, and pharmacologic prerequisites of significant hemorrhagic complications and hemostasis were analyzed., Results: The senior author's techniques for arterial and venous skeletonization, temporary clipping with cognitive or motor mapping, and ION monitoring were categorized. Vessels interfacing with tumor are labeled intraoperatively as supplying/draining the tumor, or traversing en passant, while supplying/draining functional neural tissue. Intraoperative techniques of differentiation were analyzed and illustrated. Literature search found 2 vascular-related complication domains in tumor surgery: perioperative management of excessively vascular intraparenchymal tumors and lack of intraoperative techniques and decision processes for dissecting and preserving vessels interfacing or traversing tumors., Conclusions: Literature searches showed a dearth of complication-avoidance techniques in tumor-related iatrogenic stroke, despite its high prevalence. A detailed preoperative and intraoperative decision process was provided along with a series of case illustrations and intraoperative videos showing the techniques required to reduce intraoperative stroke and associated morbidity addressing a void in complication avoidance of tumor surgery., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
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19. Acute, life-threatening postoperative pneumocephalus: emergency diagnostic and therapeutic steps with underlying pathophysiology.
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Ghare A, Dhaliwal J, Al-Mohammad A, Waraich M, and Samandouras G
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- Humans, Posture, Tomography, X-Ray Computed, Postoperative Complications diagnosis, Postoperative Complications therapy, Pneumocephalus diagnostic imaging, Pneumocephalus etiology
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- 2023
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20. Safety and efficacy of brain biopsy: Results from a single institution retrospective cohort study.
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Jozsa F, Gaier C, Ma Y, Kitchen N, McEvoy A, Miserocchi A, Samandouras G, Sethi H, Thorne L, Hill C, and Darie L
- Abstract
Introduction: Brain biopsy provides important histopathological diagnostic information for patients with new intracranial lesions. Although a minimally invasive technique, previous studies report an associated morbidity and mortality between 0.6% and 6.8%. We sought to characterise the risk linked to this procedure, and to establish the feasibility of instigating a day-case brain biopsy pathway at our institution., Materials and Methods: This single-centre retrospective case series study included neuronavigation guided mini craniotomy and frameless stereotactic brain biopsies carried out between April 2019 and December 2021. Exclusion criteria were interventions performed for non-neoplastic lesions. Demographic data, clinical and radiological presentation, type of biopsy, histology and complications in the post-operative period were recorded., Results: Data from 196 patients with a mean age of 58.7 years (SD+/-14.4 years) was analysed. 79% (n=155) were frameless stereotactic biopsies and 21% (n=41) neuronavigation guided mini craniotomy biopsies. Complications resulting in acute intracerebral haemorrhage and death, or new persistent neurological deficits were observed in 2% of patients (n=4; 2 frameless stereotactic; 2 open). Less severe complications or transient symptoms were noted in 2.5% of cases (n=5). 8 patients had minor haemorrhages in the biopsy tract with no clinical ramifications. Biopsy was non-diagnostic in 2.5% (n=5) of cases. Two cases were subsequently identified as lymphoma. Other reasons included insufficient sampling, necrotic tissue, and target error., Discussion and Conclusion: This study demonstrates that brain biopsy is a procedure with an acceptably low rate of severe complications and mortality, in line with previously published literature. This supports the development of day-case pathway allowing improved patient flow, reducing the risk of iatrogenic complications associated with hospital stay, such as infection and thrombosis., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)
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- 2023
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21. Practical, Stereotactic, Low-Profile Technique for Transcortical/Transventricular Colloid Cyst Removal Independent of Ventricular Size: Technical Note and Analysis of Approaches.
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Sefcikova V, Wong QH, and Samandouras G
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- Humans, Stereotaxic Techniques, Neurosurgical Procedures methods, Microsurgery methods, Colloid Cysts diagnostic imaging, Colloid Cysts surgery, Third Ventricle surgery
- Abstract
Background: In the presence of a dilated foramen of Monro, a transcortical, transforaminal approach is considered the safest and simplest approach for resection of colloid cysts. However, in the presence of small or normal frontal horns, numerous microsurgical approaches and, often complicated, variations have been described, invariably employing forms of stereotactic navigation., Objective: To report an alternative, accurate, microsurgical stereotactic low-profile technique., Methods: The small frontal horn is stereotactically targeted as previously described. Routine equipment is used to accurately create a novel, rigid, atraumatic surgical corridor., Results: After a 7-mm corticotomy, a peel-away catheter carrying the AxiEM stylet engages the target set as the frontal horn. All joints of the endoscope holder are locked, allowing only catheter advancement (y axis) while lateral (x axis) or anteroposterior (z axis) movements are secure. Two, 7-mm retractor blades are inserted. The extremely consistent anatomy of the foramen of Monro allows en bloc microsurgical removal without unnecessary coagulation of cyst wall or choroid plexus., Conclusion: Despite a plethora of approaches to the rostral third ventricle, in the presence of normal or small frontal horns, including creation of transcallosal/interforniceal, suprachoroidal (or transchoroidal), and sub-choroidal, colloid cyst resection does not necessarily need to be convoluted. Technical nuances of an accurate, practical, minimally invasive technique are described., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)
- Published
- 2023
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22. Intraoperative stimulation mapping of thalamocortical tracts in asleep and awake settings: novel electrophysiological, anatomical, and tractographic paradigms.
- Author
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Alexandratou A, Virjee RI, Ghare A, Sefcikova V, Micallef C, Mancini L, Waraich M, Davies DC, Keeble H, and Samandouras G
- Subjects
- Humans, Wakefulness, Brain Mapping methods, Craniotomy methods, Brain Neoplasms diagnostic imaging, Brain Neoplasms surgery, Glioma surgery
- Abstract
Objective: Despite the disabling deficits of motor apraxia and sensory ataxia resulting from intraoperative injury of the superior thalamocortical tracts (TCTs), region-specific electrophysiological localization is currently lacking. Herein, the authors describe a novel TCT mapping paradigm., Methods: Three patients, 1 asleep and 2 awake, underwent glioma resection affecting primarily the somatosensory cortex and underlying TCT. Stimulation was performed at the median, ulnar, and posterior tibial nerves. Parameters comprised single anodal pulses (duration 200-500 μsec, 2.1-4.7 Hz) with a current ranging from 10 to 25 mA. Recordings were captured with a bipolar stimulation probe, avoiding the classic collision technique. Positive localization sites were used to tractographically reconstruct the TCT in the third case., Results: Employing one electrophysiological paradigm, the TCT was localized subcortically in all 3 cases by using a bipolar probe, peak range of 19.6-29.2 msec, trough of 23.3-34.8 msec, stimulation range of 10-25 mA. In the last case, tractographic reconstruction of the TCT validated a highly accurate TCT localization within a specific region of the posterior limb of the internal capsule., Conclusions: The authors describe the first electrophysiological technique for intraoperative localization and protection of the TCT in both asleep and awake craniotomies with tractographic validation, while avoiding the collision paradigm. None of the above paradigms have been previously reported. More data are required to further validate this technique.
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- 2023
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23. Commentary: Malignant Pineal Parenchymal Tumors in Adults: A National Cancer Database Analysis.
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Sefcikova V, Wong QH, Fersht N, and Samandouras G
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- Adult, Data Management, Humans, Brain Neoplasms epidemiology, Brain Neoplasms pathology, Pineal Gland pathology, Pinealoma epidemiology, Pinealoma pathology
- Published
- 2022
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24. An interdisciplinary consensus on the management of brain metastases in patients with renal cell carcinoma.
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Hasanov E, Yeboa DN, Tucker MD, Swanson TA, Beckham TH, Rini B, Ene CI, Hasanov M, Derks S, Smits M, Dudani S, Heng DYC, Brastianos PK, Bex A, Hanalioglu S, Weinberg JS, Hirsch L, Carlo MI, Aizer A, Brown PD, Bilen MA, Chang EL, Jaboin J, Brugarolas J, Choueiri TK, Atkins MB, McGregor BA, Halasz LM, Patel TR, Soltys SG, McDermott DF, Elder JB, Baskaya MK, Yu JB, Timmerman R, Kim MM, Mut M, Markert J, Beal K, Tannir NM, Samandouras G, Lang FF, Giles R, and Jonasch E
- Subjects
- Combined Modality Therapy, Humans, Brain Neoplasms therapy, Carcinoma, Renal Cell pathology, Carcinoma, Renal Cell therapy, Kidney Neoplasms pathology, Kidney Neoplasms therapy
- Abstract
Brain metastases are a challenging manifestation of renal cell carcinoma. We have a limited understanding of brain metastasis tumor and immune biology, drivers of resistance to systemic treatment, and their overall poor prognosis. Current data support a multimodal treatment strategy with radiation treatment and/or surgery. Nonetheless, the optimal approach for the management of brain metastases from renal cell carcinoma remains unclear. To improve patient care, the authors sought to standardize practical management strategies. They performed an unstructured literature review and elaborated on the current management strategies through an international group of experts from different disciplines assembled via the network of the International Kidney Cancer Coalition. Experts from different disciplines were administered a survey to answer questions related to current challenges and unmet patient needs. On the basis of the integrated approach of literature review and survey study results, the authors built algorithms for the management of single and multiple brain metastases in patients with renal cell carcinoma. The literature review, consensus statements, and algorithms presented in this report can serve as a framework guiding treatment decisions for patients. CA Cancer J Clin. 2022;72:454-489., (© 2022 The Authors. CA: A Cancer Journal for Clinicians published by Wiley Periodicals LLC on behalf of American Cancer Society.)
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- 2022
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25. Discriminators of pseudoprogression and true progression in high-grade gliomas: A systematic review and meta-analysis.
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Taylor C, Ekert JO, Sefcikova V, Fersht N, and Samandouras G
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- Humans, Magnetic Resonance Imaging, Sensitivity and Specificity, Treatment Outcome, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Glioma diagnostic imaging, Glioma therapy
- Abstract
High-grade gliomas remain the most common primary brain tumour with limited treatments options and early recurrence rates following adjuvant treatments. However, differentiating true tumour progression (TTP) from treatment-related effects or pseudoprogression (PsP), may critically influence subsequent management options. Structural MRI is routinely employed to evaluate treatment responses, but misdiagnosis of TTP or PsP may lead to continuation of ineffective or premature cessation of effective treatments, respectively. A systematic review and meta-analysis were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses method. Embase, MEDLINE, Web of Science and Google Scholar were searched for methods applied to differentiate PsP and TTP, and studies were selected using pre-specified eligibility criteria. The sensitivity and specificity of included studies were summarised. Three of the identified methods were compared in a separate subgroup meta-analysis. Thirty studies assessing seven distinct neuroimaging methods in 1372 patients were included in the systematic review. The highest performing methods in the subgroup analysis were DWI (AUC = 0.93 [0.91-0.95]) and DSC-MRI (AUC = 0.93 [0.90-0.95]), compared to DCE-MRI (AUC = 0.90 [0.87-0.93]). 18F-fluoroethyltyrosine PET (18F-FET PET) and amide proton transfer-weighted MRI (APTw-MRI) also showed high diagnostic accuracy, but results were based on few low-powered studies. Both DWI and DSC-MRI performed with high sensitivity and specificity for differentiating PsP from TTP. Considering the technical parameters and feasibility of each identified method, the authors suggested that, at present, DSC-MRI technique holds the most clinical potential., (© 2022. The Author(s).)
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- 2022
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26. Converting sounds to meaning with ventral semantic language networks: integration of interdisciplinary data on brain connectivity, direct electrical stimulation and clinical disconnection syndromes.
- Author
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Sefcikova V, Sporrer JK, Juvekar P, Golby A, and Samandouras G
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- Brain physiology, Brain Mapping methods, Electric Stimulation, Humans, Neural Pathways physiology, Syndrome, Language, Semantics
- Abstract
Numerous traditional linguistic theories propose that semantic language pathways convert sounds to meaningful concepts, generating interpretations ranging from simple object descriptions to communicating complex, analytical thinking. Although the dual-stream model of Hickok and Poeppel is widely employed, proposing a dorsal stream, mapping speech sounds to articulatory/phonological networks, and a ventral stream, mapping speech sounds to semantic representations, other language models have been proposed. Indeed, despite seemingly congruent models of semantic language pathways, research outputs from varied specialisms contain only partially congruent data, secondary to the diversity of applied disciplines, ranging from fibre dissection, tract tracing, and functional neuroimaging to neuropsychiatry, stroke neurology, and intraoperative direct electrical stimulation. The current review presents a comprehensive, interdisciplinary synthesis of the ventral, semantic connectivity pathways consisting of the uncinate, middle longitudinal, inferior longitudinal, and inferior fronto-occipital fasciculi, with special reference to areas of controversies or consensus. This is achieved by describing, for each tract, historical concept evolution, terminations, lateralisation, and segmentation models. Clinical implications are presented in three forms: (a) functional considerations derived from normal subject investigations, (b) outputs of direct electrical stimulation during awake brain surgery, and (c) results of disconnection syndromes following disease-related lesioning. The current review unifies interpretation of related specialisms and serves as a framework/thinking model for additional research on language data acquisition and integration., (© 2022. The Author(s).)
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- 2022
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27. Correction to: CEST MRI provides amide/amine surrogate biomarkers for treatment‑naïve glioma sub‑typing.
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Mancini L, Casagranda S, Gautier G, Peter P, Lopez B, Thorne L, McEvoy A, Miserocchi A, Samandouras G, Kitchen N, Brandner S, De Vita E, Torrealdea F, Rega M, Schmitt B, Liebig P, Sanverdi E, Golay X, and Bisdas S
- Published
- 2022
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28. CEST MRI provides amide/amine surrogate biomarkers for treatment-naïve glioma sub-typing.
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Mancini L, Casagranda S, Gautier G, Peter P, Lopez B, Thorne L, McEvoy A, Miserocchi A, Samandouras G, Kitchen N, Brandner S, De Vita E, Torrealdea F, Rega M, Schmitt B, Liebig P, Sanverdi E, Golay X, and Bisdas S
- Subjects
- Amides, Amines, Biomarkers, Humans, Isocitrate Dehydrogenase genetics, Magnetic Resonance Imaging, Mutation, Brain Neoplasms diagnostic imaging, Brain Neoplasms genetics, Glioma diagnostic imaging, Glioma genetics
- Abstract
Purpose: Accurate glioma classification affects patient management and is challenging on non- or low-enhancing gliomas. This study investigated the clinical value of different chemical exchange saturation transfer (CEST) metrics for glioma classification and assessed the diagnostic effect of the presence of abundant fluid in glioma subpopulations., Methods: Forty-five treatment-naïve glioma patients with known isocitrate dehydrogenase (IDH) mutation and 1p/19q codeletion status received CEST MRI (B
1rms = 2μT, Tsat = 3.5 s) at 3 T. Magnetization transfer ratio asymmetry and CEST metrics (amides: offset range 3-4 ppm, amines: 1.5-2.5 ppm, amide/amine ratio) were calculated with two models: 'asymmetry-based' (AB) and 'fluid-suppressed' (FS). The presence of T2/FLAIR mismatch was noted., Results: IDH-wild type had higher amide/amine ratio than IDH-mutant_1p/19qcodel (p < 0.022). Amide/amine ratio and amine levels differentiated IDH-wild type from IDH-mutant (p < 0.0045) and from IDH-mutant_1p/19qret (p < 0.021). IDH-mutant_1p/19qret had higher amides and amines than IDH-mutant_1p/19qcodel (p < 0.035). IDH-mutant_1p/19qret with AB/FS mismatch had higher amines than IDH-mutant_1p/19qret without AB/FS mismatch ( < 0.016). In IDH-mutant_1p/19qret , the presence of AB/FS mismatch was closely related to the presence of T2/FLAIR mismatch (p = 0.014)., Conclusions: CEST-derived biomarkers for amides, amines, and their ratio can help with histomolecular staging in gliomas without intense contrast enhancement. T2/FLAIR mismatch is reflected in the presence of AB/FS CEST mismatch. The AB/FS CEST mismatch identifies glioma subgroups that may have prognostic and clinical relevance., (© 2022. The Author(s).)- Published
- 2022
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29. Resection of Ependymomas Infiltrating the Fourth Ventricular Floor: Anatomosurgical and Stimulation Mapping Techniques.
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Sharma P, Sefcikova V, Sanders B, Soumpasis C, Waraich M, and Samandouras G
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- Cranial Nerves, Fourth Ventricle surgery, Humans, Treatment Outcome, Ependymoma surgery, Neurosurgical Procedures methods
- Abstract
Background: Despite the importance of complete, gross total resection (GTR) of fourth ventricular ependymomas, significant morbidity and/or subtotal resections are reported, particularly when the ventricular floor is infiltrated. Step-by-step technique descriptions are lacking in the literature., Objective: To describe monitoring and stimulation mapping techniques and surgical nuances in the challenging subgroup of infiltrating fourth ventricular ependymomas by a highly illustrated, step-by-step description. Superimposed outlines of cranial nerve nuclei on the surgical field demonstrate critical anatomy and facilitate understanding in a way not previously presented., Methods: We reviewed the microanatomical and neurophysiological prerequisites of resecting a diffusively infiltrating fourth ventricular ependymoma., Results: We achieved GTR with the use of reproducible stimulating mapping and accurate cranial nerve nuclei identification., Conclusion: Enhanced microanatomical understanding, reproducible stimulation mapping, and meticulous resection techniques can result in GTR, even in diffusively infiltrating ependymomas., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)
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- 2022
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30. Early repeat resection for residual glioblastoma: decision-making among an international cohort of neurosurgeons.
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Kim AA, Dono A, Khalafallah AM, Nettel-Rueda B, Samandouras G, Hadjipanayis CG, Mukherjee D, and Esquenazi Y
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- Humans, Neurosurgeons, Neurosurgical Procedures methods, Neoplasm, Residual surgery, Cohort Studies, Disease Progression, Glioblastoma surgery, Glioblastoma pathology, Brain Neoplasms surgery, Brain Neoplasms pathology
- Abstract
Objective: The importance of extent of resection (EOR) in glioblastoma (GBM) has been thoroughly demonstrated. However, few studies have explored the practices and benefits of early repeat resection (ERR) when residual tumor deemed resectable is unintentionally left after an initial resection, and the survival benefit of ERR is still unknown. Herein, the authors aimed to internationally survey current practices regarding ERR and to analyze differences based on geographic location and practice setting., Methods: The authors distributed a survey to the American Association of Neurological Surgeons and Congress of Neurological Surgeons Tumor Section, Society of British Neurological Surgeons, European Association of Neurosurgical Society, and Latin American Federation of Neurosurgical Societies. Neurosurgeons responded to questions about their training, practice setting, and current ERR practices. They also reported the EOR threshold below which they would pursue ERR and their likelihood of performing ERR using a Likert scale of 1-5 (5 being the most likely) in two sets of 5 cases, the first set for a patient's initial hospitalization and the second for a referred patient who had undergone resection elsewhere. The resection likelihood index for each respondent was calculated as the mean Likert score across all cases., Results: Overall, 180 neurosurgeons from 25 countries responded to the survey. Neurosurgeons performed ERRs very rarely in their practices (< 1% of all GBM cases), with an EOR threshold of 80.2% (75%-95%). When presented with 10 cases, the case context (initial hospitalization vs referred patient) did not significantly change the surgeon ERR likelihood, although ERR likelihood did vary significantly on the basis of tumor location (p < 0.0001). Latin American neurosurgeons were more likely to pursue ERR in the provided cases. Neurosurgeons were more likely to pursue ERR when the tumor was MGMT methylated versus unmethylated, with a resection likelihood index of 3.78 and 3.21, respectively (p = 0.004); however, there was no significant difference between IDH mutant and IDH wild-type tumors., Conclusions: Results of this survey reveal current practices regarding ERR, but they also demonstrate the variability in how neurosurgeons approach ERR. Standardized guidelines based on future studies incorporating tumor molecular characteristics are needed to guide neurosurgeons in their decision-making on this complicated issue.
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- 2022
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31. Commentary: Permanent Cerebrospinal Fluid Diversion in Adults With Posterior Fossa Tumors: Incidence and Predictors.
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Sefcikova V, Loizidou M, and Samandouras G
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- Adult, Humans, Incidence, Hydrocephalus etiology, Infratentorial Neoplasms complications, Infratentorial Neoplasms surgery
- Published
- 2022
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32. Reforming support systems of newly diagnosed brain cancer patients: a systematic review.
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Loizidou M, Sefcikova V, Ekert JO, Bone M, and Samandouras G
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- Humans, Brain Neoplasms diagnosis, Psychosocial Support Systems
- Abstract
Purpose: Despite the increasing incidence of currently incurable brain cancer, limited resources are placed in patients' support systems, with reactive utilisation late in the disease course, when physical and psychological symptoms have peaked. Based on patient-derived data and emphasis on service improvement, this review investigated the structure and efficacy of the support methods of newly diagnosed brain cancer patients in healthcare systems., Methods: This systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols. Articles from PubMed, Embase, and CENTRAL databases were screened with six pre-established eligibility criteria, including assessment within 6 months from diagnosis of a primary malignant brain tumour. Risk of bias was evaluated using the Newcastle-Ottawa Scale and Critical Appraisal Skills Program (CASP) Qualitative Studies Checklist., Results: Of 5057 original articles, 14 were eligible for qualitative synthesis. Four studies were cross-sectional and ten were descriptive. Information given to patients was evaluated in seven studies, communication with patients in nine, and patient participation in treatment decisions in eight. Risk of bias was low in ten studies, moderate in two, and high in two., Conclusions: Techniques promoting individualised care increased perceived support, despite poor patient-physician communication and complexity of the healthcare system. Extracted data across 14 included studies informed a set of guidelines and a four-step framework. These can help evaluate and reform healthcare services to better accommodate the supportive needs of this patient group., (© 2021. The Author(s).)
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- 2022
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33. Extended testing for cognition: has awake brain mapping moved to the next level?
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Samandouras G
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- Cognition, Humans, Brain Mapping, Wakefulness
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- 2022
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34. Pineal region tumours in the sitting position: how I do it.
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Sharma P, Abdul M, Waraich M, and Samandouras G
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- Humans, Sitting Position, Thalamus, Cerebral Veins, Pineal Gland surgery, Third Ventricle
- Abstract
Background: Pineal region tumours remain challenging neurosurgical pathologies., Methods: Detailed anatomical knowledge of the posterior incisural space and its variations is critical. An opaque arachnoidal membrane seals the internal cerebral and basal veins, leading to thalamic, basal ganglia, mesencephalic/pontine infarctions if injured. Medium-size tumours can be removed en-bloc with all traction/manipulation applied on the tumour side, virtually without contact of ependymal surfaces of the pulvinars or third ventricle. Sacrifice of the cerebello-mesencephalic fissure vein may be required., Conclusions: The sitting position offers superior anatomical orientation and remains safe with experienced teams. Meticulous microsurgical techniques and detailed anatomical knowledge are likely to secure safe outcomes., (© 2021. The Author(s).)
- Published
- 2022
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35. Commentary: Postacute Cognitive Rehabilitation for Adult Brain Tumor Patients.
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Sefcikova V, Christofi G, and Samandouras G
- Subjects
- Adult, Cognition, Humans, Time Factors, Brain Injuries, Brain Neoplasms
- Published
- 2021
- Full Text
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36. Systematic review-Time to malignant transformation in low-grade gliomas: Predicting a catastrophic event with clinical, neuroimaging, and molecular markers.
- Author
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Satar Z, Hotton G, and Samandouras G
- Abstract
Background: Despite an initially indolent course, all WHO grade II, LGGs inevitably transform to malignant, WHO grades III and IV, without current curative options. Malignant transformation (MT) remains unpredictable with limited prognostic markers to steer timing of interventions. The aim of this study was to review and assign predictive value to specific clinical, molecular, and radiological markers impacting MT, thereby justifying timely therapeutic interventions., Methods: Searches of MEDLINE, Embase, and Cochrane databases were conducted from inception to April 28, 2021 and outputs were analysed in accordance with PRISMA protocol., Results: From an initial 5,032 articles, 33 articles were included, totalling 5672 patients. Forty-three prognostic factors were registered to significantly impact MT. These were categorised as 7 clinical; 14 neuroimaging; 8 biological/molecular; 3 volumetric; 5 topological; 3 histological; and 3 treatment-related. Following analysis, 10 factors were highlighted: the pre-operative prognosticators were 1. presentation with epileptic seizures; 2. VDE > 8 mm/y; 3. VDE > 4 mm/y; 4. rCBV > 1.75; 5. PTV ≥ 5 cm (65 ml); 6. PTV ≥ 100 ml; and 7. cortical involvement. The post-operative prognosticators were: (1) IDH-wt, (2) TP53 mutation, and (3) temozolomide monotherapy., Conclusions: The management of LGGs remains controversial, as conservative and invasive treatment may be associated with MT and impaired quality of life, respectively. Our review indicates that MT can be predicted by specific metrics in VDE, PTV, and rCBV, alongside cortical involvement. Additionally, patients with IDH-wt tumours TP53 mutations, or receiving TMZ monotherapy are more likely to undergo MT. Our data may form the basis of a predictive scoring system., (© The Author(s) 2021. Published by Oxford University Press, the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)
- Published
- 2021
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37. Genomic Prognosticators and Extent of Resection in Molecularly Subtyped World Health Organization Grade II and III Gliomas-A Single-Institution, Nine-Year Data.
- Author
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Lasica AB, Jaunmuktane Z, Fersht N, Kirkman MA, Dixon L, Hoskote C, Brandner S, and Samandouras G
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Brain Neoplasms mortality, Brain Neoplasms surgery, ErbB Receptors genetics, Female, Glioma mortality, Glioma surgery, Humans, Isocitrate Dehydrogenase genetics, Male, Middle Aged, Prognosis, Retrospective Studies, Survival Rate, Young Adult, Brain Neoplasms genetics, Glioma genetics, Mutation
- Abstract
Background: World Health Organization (WHO) grade II and III isocitrate dehydrogenase wild-type (IDH-wt) gliomas are often treated as WHO grade IV glioblastomas. However, cumulative evidence indicates that IDH mutation status alone is insufficient in predicting survival. The current study examines molecular and clinical markers to further prognostically stratify WHO grade II and III gliomas, in particular, IDH-wt., Methods: A single institution's records were retrospectively reviewed for molecularly stratified WHO grade II and grade III gliomas over a 9-year period (2010-2019). Clinical data, IDH1/IDH2 status, EGFR amplification, and other molecular markers were recorded and correlated to the study outcomes. These outcomes were defined as progression-free survival (PFS), overall survival (OS), and time to malignant progression (TtMP)., Results: A total of 167 and 42 WHO grade II and III gliomas, respectively, were identified, totaling 209 cases with 157 IDH1/2 mutated and 52 IDH-wt tumors. The presence of IDH1/2 mutation was associated with longer OS (P < 0.0001) and PFS (P < 0.0001) but not with TtMP (P = 0.314). Lack of EGFR amplification, younger age, and greater extent of resection (EOR) (≥80%) were identified as independent, favorable OS prognostic factors. In the IDH-wt cohort, multivariate analysis indicated that older age (P = 0.003) and lesser EOR (<80%) (P = 0.007) are associated with worse OS. In addition, EGFR amplification showed a trend toward shorter OS in the IDH-wt cohort (P = 0.073)., Conclusions: IDH1/2 mutation favors longer OS and PFS but does not protect from malignant progression. Lack of EGFR amplification, younger age and greater EOR are favorable OS prognosticators. In the IDH-wt cohort, older age and lesser EOR were linked to worse OS., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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38. Mapping and anatomo-surgical techniques for SMA-cingulum-corpus callosum gliomas; how I do it.
- Author
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Klitsinikos D, Ekert JO, Carels A, and Samandouras G
- Subjects
- Adult, Brain Neoplasms pathology, Brain Neoplasms physiopathology, Corpus Callosum physiopathology, Glioma physiopathology, Humans, Male, Motor Cortex pathology, Motor Cortex physiopathology, Postoperative Complications etiology, Speech physiology, Ultrasonics, Wakefulness, Brain Mapping, Brain Neoplasms surgery, Corpus Callosum pathology, Corpus Callosum surgery, Glioma pathology, Glioma surgery, Motor Cortex surgery, Neurosurgical Procedures adverse effects
- Abstract
Background: Awake brain mapping paradigms are variable, particularly in SMA, and not personalised to each patient. In addition, subpial resections do not offer full protection to vascular injury, as the pia can be easily violated., Methods: Mapping paradigms developed by a multidisciplinary brain mapping team. During resection, a combined subpial/interhemispheric approach allowed early identification and arterial skeletonization. Precise anatomo-surgical dissection of the affected cingulum and corpus callosum was achieved., Conclusions: In SMA-cingulum-CC tumours, a combined subpial/interhemispheric approach reduces risk of vascular injury allowing precise anatomo-surgical dissections. Knowledge of cognitive functions of affected parcels is likely to offer best outcomes.
- Published
- 2021
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39. Experience with awake throughout craniotomy in tumour surgery: technique and outcomes of a prospective, consecutive case series with patient perception data.
- Author
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Leon-Rojas JE, Ekert JO, Kirkman MA, Sewell D, Bisdas S, and Samandouras G
- Subjects
- Adult, Aged, Brain Mapping methods, Brain Neoplasms diagnostic imaging, Cohort Studies, Female, Glioma diagnostic imaging, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Prospective Studies, Treatment Outcome, Brain Neoplasms surgery, Craniotomy methods, Glioma surgery, Patient Satisfaction, Wakefulness
- Abstract
Background: Awake craniotomy is the standard of care in surgery of tumours located in eloquent parts of the brain. However, high variability is recorded in multiple parameters, including anaesthetic techniques, mapping paradigms and technology adjuncts. The current study is focused primarily on patients' level of consciousness, surgical technique, and experience based on a cohort of 50 consecutive cases undergoing awake throughout craniotomy (ATC)., Methods: Data was collected prospectively for 46 patients undergoing 50 operations over 14-month period, by the senior author, including demographics, extent of resection (EOR), adverse intraoperative events, surgical morbidity, surgery duration, levels of O
2 saturation and brain oedema. A prospective, patient experience questionnaire was delivered to 38 patients., Results: The ATC technique was well tolerated in all patients. Once TCI stopped, all patients were immediately assessable for mapping. Despite > 75% of cases being considered inoperable/high risk, gross total resection (GTR) was achieved in 68% patients and subtotal resection in 20%. The average duration of surgery was 220 min with no episodes of hypoxia. Early and late severe deficits recorded in 12% and 2%, respectively. No stimulation-induced seizures or failed ATCs were recorded. Patient-recorded data showed absent/minimal pain during (1) clamp placement in 95.6% of patients; (2) drilling in 94.7% of patients; (3) surgery in 78.9% of patients. Post-operatively, 92.3% of patients reported willingness to repeat the ATC, if necessary., Conclusions: The current ATC paradigm allows immediate brain mapping, maximising patient comfort during self-positioning. Despite the cohort of challenging tumour location, satisfactory EOR was achieved with acceptable morbidity and no adverse intraoperative events.- Published
- 2020
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40. Genetic alterations in non-syndromic, familial gliomas in first degree relatives: A systematic review.
- Author
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Vasilica AM, Sefcikova V, and Samandouras G
- Subjects
- Case-Control Studies, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic pathology, Cohort Studies, Humans, Pedigree, Brain Neoplasms diagnosis, Brain Neoplasms genetics, Glioma diagnosis, Glioma genetics, Mutation genetics
- Abstract
Objective: Despite numerous reports in syndromic gliomas, the underlying genetic and molecular basis of familial, non-syndromic gliomas, in first degree relatives, remains unclear. This rare cohort of patients harboring invasive primary brain tumors with poor prognosis may provide a potential substrate of understanding the complex genetic cascade triggering tumorigenesis., Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) 2015 and The Cochrane Handbook of Systematic Reviews of Interventions. PubMed/MEDLINE, Embase and CENTRAL databases were accessed with set inclusion and exclusion criteria., Results: Following returns of 6756 articles, systematic analysis resulted in 48 papers, with 18 case series, 4 linkage analysis, 3 case-control studies, 1 cohort study, and 22 case reports. A total of 164 first degree relatives of 72 families were analyzed. The most common genetic alterations associated with non-syndromic familial gliomas reported to affect chromosomes 17 (51.1 % germline and 9.3 % tumor mutations), 22 (15.6 % germline and 6 % tumor mutations) and 1 and 19 (4.4 % germline and 9.3 % tumor mutations), with the most commonly affected genes TP53 (8.5 %) and NF2 (3.7 %). Tumor suppressors or cell-cycle regulators, cell signaling and transcription regulation or methylation were the most common gene function categories., Conclusion: Four specific chromosomes (17, 22, 1 and 19) and two specific genes (TP53 and NF2) appear to be most commonly involved. This appears to be the first systematic review of genetic factors underlying non-syndromic glioma clustering in families. The defined list of genetic abnormalities, linked to familial gliomas, may facilitate therapeutic targets and future treatment design., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
- Full Text
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41. Results of an open label feasibility study of sodium valproate in people with McArdle disease.
- Author
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Scalco RS, Stemmerik M, Løkken N, Vissing CR, Madsen KL, Michalak Z, Pattni J, Godfrey R, Samandouras G, Bassett P, Holton JL, Krag T, Haller RG, Sewry C, Wigley R, Vissing J, and Quinlivan R
- Subjects
- Animals, Feasibility Studies, Glycogen Phosphorylase pharmacology, Humans, Muscle Fibers, Skeletal pathology, Phosphorylases metabolism, Pilot Projects, Quality of Life, Brain pathology, Glycogen Phosphorylase metabolism, Muscle, Skeletal cytology, Valproic Acid therapeutic use
- Abstract
McArdle disease results from a lack of muscle glycogen phosphorylase in skeletal muscle tissue. Regenerating skeletal muscle fibres can express the brain glycogen phosphorylase isoenzyme. Stimulating expression of this enzyme could be a therapeutic strategy. Animal model studies indicate that sodium valproate (VPA) can increase expression of phosphorylase in skeletal muscle affected with McArdle disease. This study was designed to assess whether VPA can modify expression of brain phosphorylase isoenzyme in people with McArdle disease. This phase II, open label, feasibility pilot study to assess efficacy of six months treatment with VPA (20 mg/kg/day) included 16 people with McArdle disease. Primary outcome assessed changes in VO
2 peak during an incremental cycle test. Secondary outcomes included: phosphorylase enzyme expression in post-treatment muscle biopsy, total distance walked in 12 min, plasma lactate change (forearm exercise test) and quality of life (SF36). Safety parameters. 14 participants completed the trial, VPA treatment was well tolerated; weight gain was the most frequently reported drug-related adverse event. There was no clinically meaningful change in any of the primary or secondary outcome measures including: VO2 peak, 12 min walk test and muscle biopsy to look for a change in the number of phosphorylase positive fibres between baseline and 6 months of treatment. Although this was a small open label feasibility study, it suggests that a larger randomised controlled study of VPA, may not be worthwhile., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
42. High Interrater Variability in Intraoperative Language Testing and Interpretation in Awake Brain Mapping Among Neurosurgeons or Neuropsychologists: An Emerging Need for Standardization.
- Author
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Sefcikova V, Sporrer JK, Ekert JO, Kirkman MA, and Samandouras G
- Subjects
- Brain Mapping methods, Female, Humans, Male, Monitoring, Intraoperative methods, Observer Variation, Reference Standards, Wakefulness physiology, Brain Mapping standards, Language, Monitoring, Intraoperative standards, Neurosurgeons standards, Psychology standards, Surveys and Questionnaires standards
- Abstract
Objective: Brain mapping with direct electric stimulation is considered the gold standard for maximum safe resection of tumors affecting eloquent regions. However, no consensus exists in selection and interpretation of intraoperative testing for language and other cognitive domains. Our aim was to capture and statistically analyze variability in practices in intraoperative language testing among neurosurgeons and neuropsychologists in the United States, Europe, and the rest of the world., Methods: An electronic questionnaire was developed by a multidisciplinary team at Queen Square, London, and distributed internationally through selected organized societies. The survey included 2 domains: terminology and common understanding of clinical deficits; and selection of intraoperative tests used per specific brain region. Participants were stratified by specialty, years of experience, and monthly caseload. Data were analyzed using Krippendorff α, Wilcoxon rank sum test, and Kruskal-Wallis analysis of variance., Results: A total of 137 specialists participated. A low agreement was recorded for each of the 20 questions (Krippendorff α = -0.023 to 0.312). Further subgroup analysis revealed low interrater reliability independent of specialism (neurosurgeons, α = 0.013-0.318 compared with nonneurosurgeons, α = -0.021 to 0.398; P = 0.808) and years of experience (<1 years, α = -0.003 to 0.282; 2-5 years, α = 0.009-0.327; 6-10 years, α = 0.003-0.234; and >10 years, α = -0.003 to 0.372; P = 0.200)., Conclusions: The current study documents high interrater variability, regardless of specialism and years of experience in the cohort of neurosurgeons and language specialists surveyed and may be applicable to a wider group of specialists, indicating the need to reduce interobserver, interinstitutional and interspecialty variability, reach consensus, and increase the validity, interpretation, and predictive power of intraoperative mapping., (Copyright © 2020. Published by Elsevier Inc.)
- Published
- 2020
- Full Text
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43. The use of multiparametric 18F-fluoro-L-3,4-dihydroxy-phenylalanine PET/MRI in post-therapy assessment of patients with gliomas.
- Author
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Fraioli F, Shankar A, Hyare H, Ferrazzoli V, Militano V, Samandouras G, Mankad K, Solda F, Zaccagna F, Mehdi E, Lyasheva M, Bomanji J, and Novruzov F
- Subjects
- Adolescent, Adult, Aged, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Brain Neoplasms therapy, Child, Female, Fluorine Radioisotopes chemistry, Glioma pathology, Humans, Male, Middle Aged, Precision Medicine, Tumor Burden, Young Adult, Glioma diagnostic imaging, Glioma therapy, Levodopa chemistry, Magnetic Resonance Imaging, Multimodal Imaging, Positron-Emission Tomography
- Abstract
Purpose: To determine the utility of F-fluoro-L-3,4-dihydroxy-phenylalanine (F-DOPA) PET/MRI versus cross-sectional MRI alone in glioma response assessment and identify whether the two techniques demonstrate different tumour features., Methods: F-DOPA PET/MRI studies from 40 patients were analysed. Quantitative PET parameters and conventional MRI features were recorded. Tumour volume was assessed on both PET and MRI. Using dynamic susceptibility contrast perfusion-weighted imaging, maps of cerebral blood flow (CBF) and cerebral blood volume (CBV) were obtained. Within volume of tumours of tumour features and normal-appearing white matter (NAWM) drawn on MRI, standardised uptake value (SUV)max, CBF and CBV were recorded. Presence of residual active tumour was assessed by qualitative visual assessment. Receiver operating characteristic analysis was performed univariately and on parameter combination to analyse ability to determine presence/absence of disease. Reference standard for presence of viable tissue was biopsy or clinical follow-up., Results: Median SUVmax was 3.4 for low-grade glioma (LGG) and 3.3 for high-grade glioma (HGG). There was a significant correlation between PWI parameters and WHO grade (P < 0.001), but no correlation with SUVmax. Median F-DOPA volume was 8216.88 mm for HGG and 6284.94 mm for LGG; MRI volume was 6316.57 mm and 5931.55 mm, respectively. SUVmax analysis distinguished enhancing and nonenhancing components from necrosis and NAWM and demonstrated active disease in nonenhancing regions. Visually, the modalities were concordant in 37 patients. Combining the multiparametric PET/MRI approach with all available data-enhanced detection of the presence of tumour (area under the curve 0.99, P < 0.01)., Conclusion: MRI and F-DOPA are complementary modalities for assessment of tumour burden. Matching F-DOPA and MRI in assessing residual tumour volume may better delineate the radiotherapy target volume.
- Published
- 2020
- Full Text
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44. Effect of Treatment Modalities on Progression-Free Survival and Overall Survival in Molecularly Subtyped World Health Organization Grade II Diffuse Gliomas: A Systematic Review.
- Author
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Ghaffari-Rafi A and Samandouras G
- Subjects
- Brain Neoplasms pathology, Glioma pathology, Humans, Neoplasm Grading, Progression-Free Survival, Survival Rate, Brain Neoplasms mortality, Brain Neoplasms therapy, Glioma mortality, Glioma therapy
- Abstract
Background: With the 2016 update of the World Health Organization (WHO) Classification of Tumors of the Central Nervous System incorporating molecular subtyping to histology, WHO grade II diffuse astrocytic and oligodendroglial tumors are subcategorized by distinct molecular markers. There are no reported systematic reviews quantifying differences in progression-free survival (PFS) and overall survival (OS) on the basis of molecular subtypes of WHO grade II diffuse gliomas, against the background of administered treatments., Methods: Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and the Cochrane Handbook of Systemic Reviews of Interventions, we conducted a systematic review through MEDLINE, Embase, and CENTRAL (Cochrane Central Register of Controlled Trails)., Results: For OS, the first quartile (25%), median (50%), third quartile (75%), and 95% confidence interval, respectively, were identified (in months): astrocytoma-wild-type WHO II (A-wt II): 22.8, 32.2, 40.7, and 21.6-61.2; astrocytoma-mutant WHO II (A-mt II): 69.85, 115.2, 128.4, and 55.4-164.0; oligodendroglioma WHO II (OD-II): 106.3, 163.7, 213.3, and 67.3-235.4 (P value = 0.0002). For PFS, the 25th, 50th, and 75th percentiles, and 95% confidence interval, respectively, are as follows (in months): A-wt II: 6.90, 17.45, 19.57, and 3.00-23.69; A-mt II: 37.20, 43.20, 55.63, and 35.7-60.0; OD-II: 47.42, 59.2, 88.28, and 46.3-91.2 (P value = 0.015)., Conclusions: This seems to be the first systematic review of OS and PFS in patients with WHO grade II low-grade gliomas (LGGs), against treatment modalities, in molecularly stratified subsets introduced by the WHO 2016 classification of central nervous system tumors. Overall, A-wt II was confirmed to have a significantly shorter OS than did A-mt II; no significant difference was found between OS of OD-II with A-wt II and A-mt II. In addition, all 3 molecular subtypes were found to have statistically significant differences between PFS, with OD-II having a statistically better PFS than A-mt II. These data can provide valuable prognostic insight to patients and clinicians. In addition, assessing survival differences enhances understanding of treatment recommendations against molecular markers and may facilitate future clinical trial design., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2020
- Full Text
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45. Multiple brain abscesses caused by Rhinocladiella mackenziei in an immunocompetent patient: a case report and literature review.
- Author
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Yusupov N, Merve A, Warrell CE, Johnson E, Curtis C, and Samandouras G
- Subjects
- Aged, Antifungal Agents therapeutic use, Brain Abscess drug therapy, Brain Abscess surgery, Central Nervous System Fungal Infections drug therapy, Central Nervous System Fungal Infections surgery, Debridement methods, Humans, Male, Ascomycota pathogenicity, Brain Abscess microbiology, Central Nervous System Fungal Infections microbiology
- Abstract
Primary cerebral phaeohyphomycosis due to Rhinocladiella mackenziei is an extremely rare infection carrying more than 80% mortality, with most cases reported from the Middle East region. This darkly pigmented black yeast is highly neurotropic, aggressive and refractory to most antifungal agents. Here we present an immunocompetent elderly male, presenting with multiple brain abscesses, with R. mackenziei confirmed by nuclear ribosomal repeat region sequencing, who was successfully treated by surgical debridement and intravenous voriconazole. To our knowledge this is the first case reported from the United Kingdom. We also present a review of all such cases so far reported in the English literature world-wide, which we believe is a step further to understanding the pathogenesis and establishing effective treatment of this rare, yet often fatal disease.
- Published
- 2017
- Full Text
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46. Targeting protein homeostasis in sporadic inclusion body myositis.
- Author
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Ahmed M, Machado PM, Miller A, Spicer C, Herbelin L, He J, Noel J, Wang Y, McVey AL, Pasnoor M, Gallagher P, Statland J, Lu CH, Kalmar B, Brady S, Sethi H, Samandouras G, Parton M, Holton JL, Weston A, Collinson L, Taylor JP, Schiavo G, Hanna MG, Barohn RJ, Dimachkie MM, and Greensmith L
- Subjects
- Adenosine Triphosphatases metabolism, Amyloid beta-Peptides metabolism, Animals, Cell Cycle Proteins metabolism, Cell Survival drug effects, Cells, Cultured, Clinical Trials as Topic, Endoplasmic Reticulum Stress drug effects, HSP70 Heat-Shock Proteins metabolism, Humans, Hydroxylamines pharmacology, Hydroxylamines therapeutic use, Inflammation Mediators metabolism, Mice, Muscle Contraction drug effects, Muscle Strength drug effects, Mutation genetics, Myoblasts drug effects, Myoblasts metabolism, Myoblasts pathology, Myositis, Inclusion Body pathology, Myositis, Inclusion Body physiopathology, Rats, Treatment Outcome, Valosin Containing Protein, Homeostasis, Myositis, Inclusion Body metabolism, Proteins metabolism
- Abstract
Sporadic inclusion body myositis (sIBM) is the commonest severe myopathy in patients more than 50 years of age. Previous therapeutic trials have targeted the inflammatory features of sIBM but all have failed. Because protein dyshomeostasis may also play a role in sIBM, we tested the effects of targeting this feature of the disease. Using rat myoblast cultures, we found that up-regulation of the heat shock response with arimoclomol reduced key pathological markers of sIBM in vitro. Furthermore, in mutant valosin-containing protein (VCP) mice, which develop an inclusion body myopathy, treatment with arimoclomol ameliorated disease pathology and improved muscle function. We therefore evaluated arimoclomol in an investigator-led, randomized, double-blind, placebo-controlled, proof-of-concept trial in sIBM patients and showed that arimoclomol was safe and well tolerated. Although arimoclomol improved some IBM-like pathology in the mutant VCP mouse, we did not see statistically significant evidence of efficacy in the proof-of-concept patient trial., Competing Interests: LG became an unpaid consultant to Orphazyme Aps (the owner of Arimoclomol) after completing this study. The other authors declare no competing interests., (Copyright © 2016, American Association for the Advancement of Science.)
- Published
- 2016
- Full Text
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47. Holes in the brain: Virchow–Robin spaces (giant perivascular spaces).
- Author
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Warner E, Jassar B, and Samandouras G
- Subjects
- Humans, Male, Middle Aged, Seizures etiology, Brain Diseases complications, Brain Diseases pathology, Cysts pathology
- Published
- 2015
48. Preoperative particle and glue embolization of meningiomas: indications, results, and lessons learned from 117 consecutive patients.
- Author
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Borg A, Ekanayake J, Mair R, Smedley T, Brew S, Kitchen N, Samandouras G, and Robertson F
- Subjects
- Blood Transfusion, Female, Humans, Magnetic Resonance Angiography, Magnetic Resonance Imaging, Male, Middle Aged, Neoadjuvant Therapy, Particle Size, Postoperative Complications, Retrospective Studies, Adhesives, Embolization, Therapeutic, Meningeal Neoplasms surgery, Meningioma surgery, Preoperative Care instrumentation, Preoperative Care methods
- Abstract
Background: Preoperative embolization of meningiomas remains contentious, with persisting uncertainty over the safety and efficacy of this adjunctive technique., Objective: To evaluate the safety of presurgical embolization of meningiomas and its impact on subsequent transfusion requirement with respect to the extent of embolization and technique used., Methods: One hundred seventeen consecutive patients between 2001 and 2010 were referred for embolization of presumed intracranial meningioma before surgical resection. Glue and/or particles were used to devascularize the tumor in 107 patients, all of whom went on to operative resection. The extent and nature of embolization-related complications, degree of angiographic devascularization, and the intraoperative blood transfusion requirements were analyzed., Results: Mean blood transfusion requirement during surgery was 0.8 units per case (range, 1-14 units). Blood transfusion was significantly lower in patients whose meningiomas were completely, angiographically devascularized (P = .035). Four patients had complications as a direct result of the embolization procedure. These included intratumoral hemorrhage in 2, sixth cranial nerve palsy in 1, and scalp necrosis requiring reconstructive surgery in 1 patient., Conclusion: The complication rate was 3.7%. No relationship between the embolic agent and the degree of devascularization was observed. Achieving a complete devascularization resulted in a lower blood transfusion requirement, considered an indirect measure of operative blood loss. This series demonstrates that preoperative meningioma embolization is safe and may reduce operative blood loss. We present distal intratumoral injection of liquid embolic as a safe and effective alternative to more established particle embolization techniques.
- Published
- 2013
- Full Text
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49. Serial LPS without serial imaging in idiopathic intracranial hypertension: a lesson learned.
- Author
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Rourke T, Davies S, and Samandouras G
- Subjects
- Adult, Female, Humans, Magnetic Resonance Imaging, Pseudotumor Cerebri therapy, Tomography, X-Ray Computed, Brain Neoplasms diagnosis, Ependymoma diagnosis, Medical Errors, Pseudotumor Cerebri pathology, Spinal Puncture
- Abstract
With obscure etiology, confusing terminology, and controversial management, idiopathic intracranial hypertension (IIH), most commonly known as benign intracranial hypertension, remains a common and challenging clinical problem of the general and neurological practice. The authors present a case of a patient who was diagnosed with IIH and treated with serial lumbar punctures for 4 years prior to her final diagnosis of a large intracranial tumor. This case emphasizes that IIH, an enigmatic disease that affects young females and can potentially lead to blindness, should be diagnosed after an exhausting exclusion of secondary causes of intracranial hypertension.
- Published
- 2008
- Full Text
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50. Minimally invasive biopsy of parasellar lesions: safety and clinical applications of the endoscopic, transnasal approach.
- Author
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Samandouras G, Kerr RS, and Milford CA
- Subjects
- Adult, Aged, Biopsy methods, Female, Humans, Magnetic Resonance Imaging, Male, Maxillary Sinus pathology, Middle Aged, Neoplasm Invasiveness pathology, Neuroendoscopes, Sella Turcica, Sphenoid Sinus pathology, Nasal Cavity, Neuroendoscopy methods, Skull Base Neoplasms pathology
- Abstract
The base of the skull can be affected by a variety of tumours requiring a wide range of treatment modalities. In formulating a management plan, histological diagnosis can play an essential role. Existing methods of skull base biopsy, especially in the anatomically critical parasellar region, include either prolonged open skull base approaches or image-guided needle biopsies. The latter methods can be time-consuming and cannot reliably avoid surrounding critical neurovascular structures. The experience with an endoscopic, transnasal biopsy of parasellar tumours in selected patients is presented. A preliminary series of 11 patients harbouring parasellar lesions with some degree of extension to the sphenoid or maxillary sinus underwent endoscopic, transnasal biopsy. The procedure was diagnostic in all cases. There was no operative mortality and minimal morbidity only recorded. The biopsy results affected the patients' management and, based on these results, major skull base surgery was avoided in four cases. Direct endoscopic visualization prompted avoidance of a vascular catastrophe of an atypical vascular lesion. The endoscopic, transnasal biopsy appears to offer a number of advantages over existing methods in selected patients. It is minimally invasive as it employs the use of natural osseous corridors. Tissue sampling under direct visualization minimizes the risks of negative biopsies or damage to critical neurovascular structures. The use of additional imaging employed by image-guided needle biopsies in not necessary. When planning treatment of parasellar tumours, the endoscopic, transnasal route should be considered.
- Published
- 2005
- Full Text
- View/download PDF
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