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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The corticospinal motor evoked potential was investigated as a monitoring index of motor function to perform maximal resection of brain tumors located around the motor cortex in 37 patients with glioma. Tumor resections were performed under general anesthesia with muscle relaxant and completely controlled ventilation. No special arrangements for anesthesia were required. Direct cortical stimulation revealed that if one electrode was placed on the posterior half of the precentral gyrus, the D-wave could be recorded even when using an electrode separation of 10 mm, and the amplitude was larger with anodic rather than cathodic stimulation. Monitoring of the D-wave enabled the function of the corticospinal tract to be evaluated selectively. Postoperative persistent motor disturbance remained in six patients who had a decrease of over 30% in amplitude of the D-wave during tumor resection. A decrease of less than 30% may indicate postoperative preservation of motor function, including transient motor disturbance with subsequent complete recovery. Intraoperative monitoring of the D-wave is suitable for open cranial surgery with general anesthesia, can detect the primary motor cortex, and allow maximal resection of brain tumors located around the motor cortex.
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PMID:Intraoperative monitoring of the corticospinal motor evoked potential (D-wave): clinical index for postoperative motor function and functional recovery. 1518 55

Despite a better understanding of the organization of the cortical network underlying the semantic system, very few data are currently available regarding its anatomo-functional connectivity. Here, we report on a series of 17 patients operated on under local anaesthesia for a cerebral low-grade glioma located within the dominant hemisphere. Prior to and during resection, intraoperative electrical stimulation was used to map sensorimotor and language structures so that permanent neurological deficits could be avoided. In a number of cases, cortical and subcortical stimulation caused semantic paraphasias. Using postoperative MRI, we correlated these functional findings with the anatomical locations of the sites where semantic errors were elicited by stimulation, especially at the subcortical level, with the aim of studying the connectivity underlying the semantic system. In temporal gliomas, cortical sites involved in semantic processing were found around the posterior part of the superior temporal sulcus, with subcortical pathways reproducibly located under the depth of this sulcus. In insular gliomas, although stimulation elicited no semantic disturbances at the cortical level, such semantic paraphasias were generated at the level of the anterior floor of the external capsule. In frontal tumours, cortical regions implicated in semantics were detected in the lateral orbitofrontal region and dorsolateral prefrontal cortex, with subcortical fibres located under the inferior frontal sulcus. All these eloquent structures were systematically preserved, thereby avoiding permanent postoperative deficits. Our results provide arguments in favour of the existence of a main ventral subcortical pathway underlying the semantic system, within the dominant hemisphere, joining the two essential cortical epicentres of this network: the posterior and superior temporal areas, and the orbitofrontal and dorsolateral prefontal regions. Such a ventral stream might anatomically partly correspond to the inferior fronto-occipital fasciculus.
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PMID:New insights into the anatomo-functional connectivity of the semantic system: a study using cortico-subcortical electrostimulations. 1570 10

Glioma surgery in functional areas has undergone a dramatic development these last few years, thanks to improvements in both intraoperative functional imaging and direct electrical stimulation of cortical areas or association pathways. The goal of these techniques to achieve complete as possible surgical removal of tumors located in eloquent areas (sensitive, motor and language areas) with minimal risk of permanent sequelae. To be reliable, a rigorous methodology is required. Current cortical mapping is very easy to achieve, whereas mapping of association pathways will require much more experience. In case of tumors located in somatosensorial or language areas, the difficulties related to accurate sub cortical localization are combined with these of local anesthesia and the best task choice to evaluate the integrity of cognitive functions. These functional techniques allow total or sub total removal in 52% to 76.2% of patients. Transient worsening is observed in 13% to 80% of the patients; the rate of permanent sequelae averages 4%.
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PMID:[Usefulness of direct electrical stimulations during surgery for gliomas located within eloquent brain regions]. 1629 79

Although advances in diffusion tensor imaging have enabled us to better study the anatomy of the inferior longitudinal fasciculus (ILF), its function remains poorly understood. Recently, it was suggested that the subcortical network subserving the language semantics could be constituted, in parallel with the inferior occipitofrontal fasciculus, by the left ILF, joining the posterior occipitotemporal regions to the temporal pole, then relayed by the uncinate fasciculus connecting the anterior temporal pole to the frontobasal areas. Nevertheless, this hypothesis was solely based on neurofunctional imaging, allowing a cortical mapping but with no anatomofunctional information regarding the white matter. Here, we report a series of 12 patients operated on under local anaesthesia for a cerebral low-grade glioma located within the left temporal lobe. Before and during resection, we used the method of intraoperative direct electrostimulation, enabling us to perform accurate and reliable anatomofunctional correlations both at cortical and subcortical levels. In order to map the ILF. Using postoperative MRI, we correlated these functional findings with the anatomical locations of the sites where language disturbances were elicited by stimulations, both at cortical and subcortical levels. Our goal was to study the potential existence of parallel and distributed language networks crossing the left dominant temporal lobe, subserved by distinct subcortical pathways--namely the inferior occipitofrontal fasciculus and the ILF. Intraoperative stimulation of the anterior and middle temporal cortex elicited anomia in four patients. At the subcortical level, semantic paraphasia were induced in seven patients during stimulation of the inferior occipitofrontal fasciculus, and phonological paraphasia was generated in seven patients by stimulating the arcuate fasciculus. Interestingly, subcortical stimulation never elicited any language disturbances when performed at the level of the ILF. In addition, following a transient postoperative language deficit, all patients recovered, despite the resection of at least one part of the ILF, as confirmed by control MRI. On the basis of these results, we suggest that the "semantic ventral stream" could be constituted by at least two parallel pathways within the left dominant temporal lobe: (i) a direct pathway, the inferior occipitofrontal fasciculus, that connects the posterior temporal areas and the orbitofrontal region, crucial for language semantic processing, since it elicits semantic paraphasia when stimulated; (ii) and also possibly an indirect pathway subserved by the ILF, not indispensable for language, since it can be compensated both during stimulation and after resection.
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PMID:Does the left inferior longitudinal fasciculus play a role in language? A brain stimulation study. 1726 96

The aim of brain glioma surgery is to maximize the quality of resection, while minimizing the risk of sequelae. Due to the frequent location of gliomas in "eloquent areas" and because of major interindividual anatomofunctional variability, the cortical functional organization, effective connectivity and potential for plasticity must be studied for each patient individually. Consequently, in addition to preoperative functional neuroimaging, intraoperative electrostimulation (IES) can be used, under general anesthesia for motor mapping or on awake patient for language and cognitive mapping. This is an easy, accurate, reliable, and safe technique of detection of both cortical and subcortical functionally essential structures. Thus, IES enables: (i) to study the individual cortical functional organization before any resection; (ii) to understand the pathophysiology of areas involved by gliomas; (iii) to map the subcortical structures along the resection, allowing a study of the anatomofunctional connectivity; (iv) to analyze the mechanisms of on-line short-term plasticity, using repeated IES; (v) to tailor the resection according to individual cortico-subcortical functional boundaries, enabling to optimize the benefit:risk ratio of surgery. Moreover, IES can be combined with perioperative functional neuroimaging, before and after surgery, to validate these noninvasive techniques and to better understand the short-term and long-term plasticity mechanisms based on functional cortical reshaping and connectivity changes. Such individual knowledge allows planning multiple-stages surgery. In conclusion, IES enables to increase the impact of surgery on the natural history of gliomas, to preserve the quality of life, and to better understand the dynamic functional anatomy of the brain.
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PMID:Contribution of cortical and subcortical electrostimulation in brain glioma surgery: methodological and functional considerations. 1808 92

Optic pathway glioma associated with neurofibromatosis 1 has a classically indolent course. However, involvement of the optic radiations is relatively rare and is associated with a more aggressive course. A three-year-old girl presented with strabismus and loss of vision in the left eye with relative afferent pupillary defect and optic disc pallor. She had multiple cafiota au lait spots. Visually evoked potential was suggestive of an optic nerve conduction defect and magnetic resonance imaging of the brain was suggestive of an optic pathway glioma involving the optic nerves, the optic chiasma and the optic tracts. The optic radiations and the dendate nuclei had hamartomas. Optic nerve biopsy confirmed pilocytic astrocytoma. Radical radiotherapy under general anesthesia was subsequently given. This case report aims to highlight the involvement of the optic radiations and the unusually aggressive clinical course in this case.
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PMID:A case of neurofibromatosis 1 presenting with optic pathway glioma with an early onset and an aggressive course. 1829 34

Asleep-awake-asleep technique of anesthesia is used during awake craniotomy with or without securing airway. We assessed this technique using laryngeal mask airway (LMA) in two patients. Patients underwent awake craniotomy for epilepsy surgery and the removal of a frontotemporal glioma. After anesthesia induction, airway was secured using LMA. Anesthesia was maintained using oxygen, nitrous oxide and sevoflurane, supplemented with an infusion of propofol and remifentanil. Twenty minutes before corticography, anesthesia was discontinued and LMA removed. Both patients were awake and cooperative during the neurological assessment and surgery on eloquent areas. The LMA was reinserted before the closure of the dura and remained in place until the end of surgery. Both patients had no recall of events under anesthesia, although experienced mild pain and discomfort during awake phase of surgery. Both expressed complete satisfaction over the anesthetic management. Asleep-awake-asleep technique using LMA offers airway protection. The painful aspect of surgery can be performed under anesthesia, hence minimizing the duration of stress and pain. Patients remained awake and cooperative throughout the time of neurological testing.
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PMID:Anesthesia management of awake craniotomy performed under asleep-awake-asleep technique using laryngeal mask airway: report of two cases. 1831 Aug 41

On December 14, 1883, William Osler, then pathologist at the Montreal General Hospital, presented the specimen of a brain with an almond-sized glioma beneath the right motor cortex to the Montreal Medico-Chirurgical Society. The brain specimen was from a young woman who had suffered from intermittent Jacksonian seizures for 14 years and had eventually died in status epilepticus. Aware of the pioneering removal of a tumor from the cortex reported on in 1885 by Bennett and Godlee, Osler wrote of his case, "this was an instance in which operation would have been justifiable and possibly have been the means of saving life." In 1953, a young man with Jacksonian attacks that began in his foot underwent removal of a Grade I glioma from the central fissure. The operation was performed in an awake craniotomy during which cortical mapping was used to define the motor and sensory cortices. Treatment with focal radiation followed, and afterward the patient became seizure-free, stopped taking anticonvulsant medication, and has led an active life over the past 50 years. Reference is made to the experiences of Sherrington, Cushing, and Penfield with cortical stimulation in the awake patient under regional anesthesia as an effective aid to surgery for epileptogenic lesions, tumors, and vascular malformations. Their technique allows for maximal resection with minimal neurological deficits. Over the past 20 years, this approach has been adopted effectively in many neurosurgical centers.
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PMID:Osler vindicated: glioma of the leg center with Jacksonian epilepsy; removal and cure, with a 50-year follow-up. Historical vignette. 1926 35

A nasal glioma was discovered during routine examination of the nasal cavity patency of a newborn. An excision of the lesion was done by an intranasal approach under general anaesthesia. The intranasal endoscopic approach is strongly recommended for the removal of intranasal gliomas. Angled (30 or 70 degrees) endoscopy allows visualisation of the cribriform plate which helps to rule out an intracranial extension.
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PMID:[Case report on a nasal glioma: review of the literature]. 1940 21

Despite remarkable advancements in brain tumor surgery after the introduction of operating microscopes and neuronavigation systems, precise removal of infiltrative brain tumors such as gliomas remains difficult. In many cases, the margins of these tumors are unclear even under the microscope. Neuronavigation based on preoperative images also is unreliable after the "brain shift" phonomenon following cerebrospinal fluid (CSF) withdrawal and/or tumor removal. Reports, however, have claimed total or near total resection of glioma is associated with better prognosis than subtotal or less amount of resection. Thus, advanced image-guided neurosurgery is expected to play an important role in achieving precise resection of such intrinsic and infiltrative brain tumors. However, caution must be exercised regarding the accuracy and reliability of image-guidance. Image-guided surgery therefore, should be supported and validated by using techniques for neurophysiological monitoring such as motor-evoked potential (MEP) under general anesthesia and monitoring of speech and motor function under awake craniotomy, if tumor is located in eloquent areas. There has been a worldwide increase in the installation of intraoperative MRI (iMRI) units in the operating room. Various lay-outs of the operating room and iMRI units with different magnetic field strengths ranging from 0.12T to 3.0T are currently in use. In 2006, we introduced 2 operation theaters with iMRI units, a 0.4T, relatively low (0.4T) and high (1.5T) magnetic-field strengths were installed at the Nagoya University Hospital and the Nagoya Central Hospital, one of our affiliated hospitals, respectively. In this paper, we discuss the, effectiveness of iMRI, as well as several problems associated with its application on the basis of the relevant literatures and our experience of more than 400 operations performed at the 2 different iMRI operation theaters, Brain THEATER and BrainSUITE.
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PMID:[Image-guided neurosurgery using intraoperative MRI]. 1961 60


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