744 resultados para INTRACRANIAL MENINGIOMAS


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Eine dreizehnjährige, weibliche, nicht kastrierte Hauskatze wurde zur chirurgischen Therapie eines multiplen Meningeoms in der Kleintierklinik des Tierspital Bern vorgestellt. Eine leichtgradige generalisierte Ataxie wurde beobachtet, die Propriozeption war generalisiert herabgesetzt und der Drohreflex war beidseitig reduziert. Es wurden eine prä- und eine postoperative Magnetrezonanztomographie durchgeführt. Drei supratentoriale extra-axiale Raumforderungen wurden diagnostiziert. Eine vierte Masse wurde infratentorial extra-axial über der linken zerebellären Hemisphere lokalisiert. Eine Herniation des kaudoventralen Kleinhirn (Vermis) von ungefähr einem Zentimeter Länge durch das Foramen magnum wurde beobachtet. Eine zervikale Syringohydromyelie wurde als Zufallsbefund diagnostiziert. Die Meningeome wurden durch 3 Kraniotomiestellen entfernt. Zwei Jahre nach der Operation ist die Katze normal. Anhand der vorhandenen Literatur wird die tumor-assoziierte Syringohydromyelie besprochen. Die Therapie der Syringohydromyelie sollte gegen den kausalen pathologischen Prozess (z.B. intrakranieller Tumor) für die Liquorzirkulationsstörung gerichtet sein.

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Background: Approximately 60% of meningiomas are associated with peritumoral edema. Various causative factors have been discussed in the literature. The objective of this study was to investigate the correlation of PTBE with clinical, radiologic, and surgical aspects and recurrence of meningiomas. Methods: Sixty-one patients with benign meningiomas were chosen for surgical treatment by the Group of Brain Tumors and Metastasis of the Department of Neurosurgery. All patients underwent complete surgical resection (Simpson grades I and 2), and those with atypical and malignant histopathologic grades were excluded. Tumors located in the cavernous sinus, tuberculum sellae, foramen magnum, ventricles, and petroclival region were excluded. Results: Edema extension had a positive correlation with the higher recurrence rates (P=.042) and with the presence of irregular margins (P<.011) on bivariate analysis. Meningiomas with larger edema sizes also showed correlation with large meningiomas (P=.035), and the ones with smaller edema sizes correlated with the tentorial location (P=.032). Multivariate analysis showed an association between PTBE and the presence of seizures (odds ratio, 3.469), large meningiomas (odds ratio, 15.977), and for each cubic centimeter added to its size, the risk of edema increased 1.082 times (odds ratio). Conclusion: Peritumoral brain edema may be related to the invading potential of meningiomas and may play a role in the recurrence potential of the tumor. As a consequence, it is reasonable to consider the presence of edema as an additional factor to be taken into account when mapping out strategies for the treatment of meningiomas. (C) 2008 Elsevier Inc. All rights reserved.

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Tentorial meningiomas comprise 3-5% of the intracranial meningiomas. Different locations and sinus invasion require special surgical skills. This study aimed to analyze factors influencing the outcome of 29 patients (30 tumors) with tentorial meningiomas surgically treated. The study included 22 female and seven male patients, with age of 18-76 years old, and a follow-up of 6-179 months. Eight tumors were located on the inner tentorial ring, 15 on the outer ring, four were falcotentorial, and three attached/invading the torcula. Outcome was analyzed using survival and recurrence-free survival (RFS) curves. Twenty-seven tumors were WHO grade I and three were grades II-III. Total and subtotal resections were reached in 87.5% and 12.5% of tumors. Survival was better for patients with grade I tumors and similar according to sex, location, size, and extent of resection. Recurrence/regrowing rate was 12.5%. RFS curves were better for patients with grade I or with radical resection and similar according to sex, location, and size. There was no operative mortality. Permanent postoperative cranial nerve deficits occurred in 9.7% (all inner ring tumors). Despite being many times large-sized, surgical treatment of tentorial meningiomas gives good results. Prognostic factors for recurrence were histopathologic grade III and subtotal resection. Radical resection allowed better results. Nevertheless, subtotal resection may be acceptable for cases with cranial nerves or sinuses invasions.

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Most meningiomas are benign tumours of arachnoidal origin, although a small number have high proliferative rates and invasive properties which complicate complete surgical resection and are associated with increased recurrence rates. Few prognostic indicators exist for meningiomas and further research is necessary to identify factors that influence tumour invasion, oedema and recurrence. Paraffin sections from 25 intracranial meningiomas were analysed for expression of the proteins vascular endothelial growth factor (VEGF), VEGF receptors Flt1 and Flk1, E-cadherin, metalloproteinases 2 and 9 (MMP2, MMP9), CD44, receptor for hyaluronic acid-mediated motility (RHAMM), hyaluronic acid (HA), CD45, cyclooxygenase 2 (COX2), brain fatty acid binding protein (BFABP), Ki67, and proliferating cell nuclear antigen (PCNA). Correlations among protein expression were found for several markers of proliferation (Ki67, PCNA, MI) and microvessel density (MVD). COX2 expression increased with increasing with tumour grade and correlated with Ki67, PCNA, MI, MVD, and BFABP. BFABP expression also correlated with Ki67 and PCNA expression. Relationships were also identified among angiogenic factors (VEGF, Flt1, Flk1) and proliferation markers. Oedema was found to correlate with MMP9 expression and MMP9 also correlated with proliferation markers. No correlations were found for MMP2, E-cadherin, or CD44 in meningiomas. In conclusion Ki67, PCNA, MI, MVD, BFABP, and COX2 were significantly correlated with meningioma tumour grade and with each other. These findings, by correlating both intracellular fatty acid transport and eicosanoid metabolism with tumour proliferation, as determined by Ki67 labelling and mitotic index, suggest fatty acids are involved in the progression of meningiomas.

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Tentorial meningiomas account for 2% to 3% of all intracranial meningiomas. The authors present their experience with posterior fossa tentorial meningiomas, and discuss the main features, which influence approaches and complications of the different surgical techniques. Twenty-four patients had meningiomas localized predominantly in posterior fossa. Their historical records and radiologic examinations were reviewed in accordance with Simpson`s classification. The extension of tumor removal was Simpson grade I in 12 patients (50%), grade II in 12 patients (50%), and grades III and IV in none of the patients. In 22 patients (91.66%), the meningioma was classified as grade I and in 2 cases (8.33%) classified as grade 11 (atypical meningioma). The combined supra/infiratentorial was employed in 12 cases, and complete resections were most common with this approach compared with retrosigmoid technique. Postoperative complications occurred in 10 patients (41.6%) with major deficits in 3 patients (12.5%). The authors believe that careful preoperative choice of the surgical approach should be based Oil tumor location and extension. It is then possible to achieve the best radical microsurgical tumor resection, avoiding additional injury to neurovascular structures.

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Meningiomas are recognized as the most common late complication following radiotherapy. However, cytogenetic studies in childhood atypical radiation-induced meningioma are sporadic, mainly because this condition generally occurs after a long latent period. In the present study we show the results of conventional and molecular cytogenetics in a 14-year-old boy with a secondary atypical meningioma. Apart from numerical changes, we found complex aberrations with the participation of chromosomes 1, 6 and 12. The invariable presence of loss of 1p was demonstrated by fluorescent in situ hybridization (FISH) analysis with probes directed to telomeric regions and by comparative genome hybridization (CGH). Previous cytogenetic studies on adult spontaneous and radiation-associated meningiomas showed loss of chromosome 22 as the most frequent change, followed by loss of the short arm of chromosome 1. To the best of our knowledge this is the first report of highly complex chromosome aberrations in the pediatric setting of meningioma.

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In the present study, we described a rare association of polycystic liver disease (PCLD) with intracranial meningiomas in patients included on a liver transplant list, focusing on the diagnosis, treatment and possible association with any genetic alterations. Two female patients, aged 39 and 49 years were included on a liver transplant list due to extensive PCLD, with symptoms related to an abdominal compartmental syndrome. Screening for extrahepatic manifestation revealed a right frontal meningioma in the first patient, and a parietal posterior calcified meningioma in the second patient, measuring 1 and 7x3x2 cm in diameter, respectively. Following tumor removal, the histological pattern was compatible with fibrous and transitional meningioma, respectively. Cytogenetic studies conducted following surgery did not reveal any changes in metaphase chromosomes. The postoperative follow-up for the two patients was uneventful, without complications, with the patients remaining on a liver transplant waiting list. We conclude that screening for extrahepatic manifestations of PCLD is mandatory, as certain lesions require treatment prior to liver transplantation. The lack of a genetic or familial association between these two cases show they are likely to have occurred by chance, rather than representing a previously unrecognized association between polycystic liver disease and cranial meningioma.

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The management of patients with small, often asymptomatic meningiomas is controversial and includes observation, microsurgery (MS) and stereotactic radiosurgery (SRS). The purpose of this retrospective study was to analyze the morbidity and the extent of removal after MS for small (< or =3 cm) intracranial meningiomas and compare these results to those of SRS reported in the literature.

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Meningioma is the most frequently observed primary brain tumour in cats. Usually, it is associated with an intracranial expansion with consequent brain compression, oedema and brain herniation. Typical features of feline intracranial meningiomas are hyperostosis of the adjacent bone and intratumoral mineralisation. We describe a 13-year-old male neutered cat with a 1-year history of behavioural change. At clinical and neurological examination the cat showed signs consistent with right-sided forebrain lesion. Magnetic resonance images showed a right-sided extra-axial contrast enhancing mass in the region of the frontotemporal lobe. The overlying bone of the calvarium showed a marked defect with extracranial expansion of the tissue. Surgery was performed and the tumour could be exposed by a right-sided temporal approach. After extension of the bony defect the mass could be removed properly. The cat recovered well from surgery and a 12-month follow-up showed no persistent neurological deficits. Histopathological assessment of the tumour revealed a transitional grade 1 meningioma. Despite osteolysis and extracranial expansion of the tumour differentials should include menigioma in feline intracranial neoplasms.

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Object: The purpose of the study was to assess the role of Gamma Knife surgery (GKS) in secondary trigeminal neuralgia (TN) caused by space-occupying lesions. Methods: From July 2010 till January 2015, 17 patients had GKS for secondary TN caused by intracranial lesions. The primary outcome was tumor control. The secondary outcomes were the alleviation of pain and the eventual secondary effects. Covariates were the age, duration of symptoms, duration till alleviation etc. Results: The mean age in this series was 63.3 years (range 39-79). The mean follow-up period was 1.85 years (range 0.5-3). Nine (52.9%) were meningiomas, five (29.4%) trigeminal schwannomas, two (11.8%) brain metastases and one (5.9%) arteriovenous malformation (AVM). Eight were located on the right side and nine on the left side. The mean duration of TN was 13.5 months (range 0.5-160). Follow-up was available for 16 patients (94.1%). Pain alleviation appeared after a mean time of 4.6 months (1-11) in 15 patients (88.2%). Five (29.4%) patients completely stopped medication in a mean time of 7 months (range 1-13) and three (17.6%) decreased it at half of the initial doses. No patient developed new hypoesthesia or other cranial nerve complication. The marginal doses for meningiomas and trigeminal schwannomas were 12 Gy (12-14), for metastasis 20 (20-20) and for AVM 24 Gy. The mean target volume was 1.84 cc (range 0.12-8.10). The mean prescription isodose volume was 2.65 cc (0.19-11.90). The mean maximal diameter was 19.9 (range 9-36). The mean number of isocenters was 14.2 (4-27). The mean duration was 76.9 minutes (range 25-172). The mean conformity, selectivity, Paddick and gradient index were: 0.99 (range 0.955-1), 0.701 (range 0.525-0.885), 0.694 (range 0.525-0.885) and 2.904 (range 2.654-3.371). At last follow-up, tumor decreased in 10 (58.8%) patients, was stable in 6 (35.3%) and increased in one (5.9%), the latest at 6 months. Conclusions: Gamma Knife surgery is safe and effective in treating intracranial lesions presenting with secondary TN. The initial pain freedom response was close to 90%, while having no secondary effect. Pain alleviation is achieved even in the absence of a volume variation of the lesions.

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Objective: Report our experience with trigone ventricular meningiomas and review the surgical approaches to the trigone. Method: From 1989 to 2006, six patients with meningiomas of the trigone of the lateral ventricles underwent microsurgical resection. Their clinical features, image, follow up, and surgical approaches were retrospectively analyzed. Results: Five patients presented with large and one with small volume meningioma. Unspecific symptoms occurred in three patients; intracranial hypertension detected in three patients; homonymous hemianopsy in three; and motor deficit present in one patient. Three patients were operated by transparietal transcortical approach, two by middle temporal gyrus approach, and one by parieto-occipital interhemispheric precuneus approach. Total resection was achieved in all patients without additional deficits. Conclusion: Judicious preoperative plan, adequate knowledge of anatomy, and use of correct microsurgical techniques are fundamental in achieving complete resection of trigone meningioma with low morbidity.

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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

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Os meningiomas são os tumores intracranianos mais frequentes, originando-se das meninges que revestem o cérebro e cordão espinhal. Apesar de terem sido um dos primeiros neoplasmas sólidos estudados citogeneticamente, ainda são escassos os estudos genéticos e epigenéticos nesses tumores. O presente trabalho teve como objetivo investigar alterações genéticas e epigenéticas que pudessem contribuir na iniciação e progressão tumoral em meningiomas na população paraense. Essa tese está subdivida em três capítulos. No Capítulo I foi investigada a associação entre o polimorfismo MTHFR C677T e meningioma em 23 pacientes da população paraense, utilizando 96 indivíduos sem histórico de lesões pré-neoplásicas como grupo controle. Essa associação não foi encontrada, apesar de sugerir um aumento não estatisticamente significante no risco de desenvolver meningioma em portadores do genótipo TT quando comparados ao genótipo CC. No Capítulo II foi avaliado o padrão de metilação em duas famílias do microRNA124 em meningiomas na população paraense. Hipermetilação na região promotora de miRN124a2 e miRNA124a3 parece ser um evento frequente, uma vez que foi encontrada em 73,9% e 69,56% das amostras analisadas, respectivamente. No Capítulo III, foi analisado o padrão de metilação dos genes APC, BRCA1, CDH1, CDH13, CDKN2A, DAPK1, ESR1, FHIT, GSTP1, MGMT, MLH1, NEUROG1, PDLIM4, PTEN, RARB, RASSF1, RUNX3, SOCS1, TIMP3, TP73, VHL e WIF1 em um meningioma de grau I e um de grau II através de uma placa comercial desenvolvida através da tecnologia MethylScreen. O padrão de metilação do gene CDKN2B também foi analisado na amostra coletada em 25 pacientes com meningioma através da conversão por bissulfito, PCR e sequenciamento direto. O gene RASSF1A apresentou-se metilado em 16,73% e 63,66% dos sítios CpGs analisados na amostra de meningioma de grau I e grau II, respectivamente. O gene RUNX3 se apresentou metilado apenas na amostra de grau II em 52,88% dos sítios CpG analisados. Nossos resultados apontam a importância das alterações epigenéticas na tumorigênese e progressão tumoral em meningiomas.

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The purpose of this study was to analyse retrospectively a feline population with intracranial neoplastic diseases, to document seizure patterns in these animals and to determine whether partial seizures were more frequently associated with structural brain lesions then generalised seizures. In addition, a comparison was made within the population with intracranial neoplasia between two groups of cats: one with and one without seizures. Special emphasis was given to the evaluation of tumour type, localisation and size of the lesion and its correlation with seizure prevalence. Sixty-one cats with histopathological diagnosis of intracranial tumour were identified. Fourteen cats (23%; group A) had a history of seizure(s). Forty-seven cats (77%; group B) had no history of seizure(s). Generalised tonic-clonic seizures were seen in eight cats (57%) and were the most common seizure pattern in our cats with intracranial neoplasia. Clusters of seizures were observed in six cats. Status epilepticus was observed in one patient. The mean age of the cats was 7.9 years within group A (median 8.5) and 9.3 years (median 10) within group B. The cats with lymphoma within both groups were significantly younger than cats with meningioma. In both groups meningioma and lymphoma were confirmed to be the most frequent tumour type, followed by glial cell tumours. The prevalence of the seizures in patients with glial cell tumours was 26.7%, 26.3% in patients with lymphomas and 15% in cases with meningiomas. In 33 cases (54.1%) the tumours were localised in the forebrain, 15 tumours (24.6%) were in the brainstem, four (6.6%) in the cerebellum and nine tumours (14.7%) had multifocal localisation. Parietal lobe and basal ganglia mostly affected group A. In group B tumours were most frequently located in the parietal and frontal lobes as well as in the diencephalon. A positive association was documented between the localisation of a tumour in the forebrain and seizure occurrence.

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Interactions between testosterone, estradiol, and inhibin in the control of gonadotrophin secretion in males are poorly understood. Castrated rams were treated with steroid-free bovine follicular fluid (bFF), testosterone, or estradiol and for 7 d (2 x 2 x 2 factorial design). Given independently, none of the exogenous hormones affected follicle-stimulating hormone (FSH) concentrations, but the combination of one or both steroids with bFF reduced FSH secretion. Testosterone and estradiol reduced luteinizing hormone (LH) pulse frequency (there was no synergism), and bFF had no effect. Plasma prolactin concentrations were not affected by any treatment. To locate the central sites of steroid action, castrated rams were bilaterally implanted in the preoptic area (POA), ventromedial nucleus (VMH), or arcuate nucleus (ARC). These implants did not affect FSH or prolactin concentrations, or LH pulse amplitude. The frequency of the LH pulses was not affected by testosterone in any site. Estradiol located in the ARC, but not the POA or VMH, decreased LH pulse frequency. In summary, FSH secretion is controlled by synergistic interactions between inhibin and estradiol or testosterone, whereas GnRH/LH pulse frequency is controlled by testicular steroids. Estradiol acts partly, at least, in the ARC, but the central site of action, testosterone remains unknown.