Search results for "Brain Neoplasm"
showing 10 items of 249 documents
A preliminary PET radiomics study of brain metastases using a fully automatic segmentation method
2020
AbstractBackgroundPositron Emission Tomography (PET) is increasingly utilized in radiomics studies for treatment evaluation purposes. Nevertheless, lesion volume identification in PET images is a critical and still challenging step in the process of radiomics, due to the low spatial resolution and high noise level of PET images. Currently, the biological target volume (BTV) is manually contoured by nuclear physicians, with a time expensive and operator-dependent procedure.This study aims to obtain BTVs from cerebral metastases in patients who underwent L-[11C]methionine (11C-MET) PET, using a fully automatic procedure and to use these BTVs to extract radiomics features to stratify between p…
Cell death and oxidative stress in gliomas.
1999
In gliomas, apoptosis and necrosis are determined by a number of promoting and inhibiting factors including oxidative cell stress mediated by nitric oxide synthases (NOS) and reduced by superoxide dismutases. Therefore, in 46 gliomas (including astrocytomas, oligodendrogliomas, oligo-astrocytomas, and glioblastomas), the relationship of apoptosis and necrosis and the expression of apoptosis-promoting (p53, bax, Fas, Fas-L) and inhibiting (bcl-2) factors as well as of different isoforms of NOS (NOSb, NOSe, NOSi) and manganese superoxide dismutase (MnSOD) were studied. Apoptosis was measured in situ by the TUNEL method while expression profiles of apoptosis-related and oxidative stress-associ…
Trigeminal Neuralgia and Cerebellopontine‐Angle Lipoma in a Child
2001
Trigeminal neuralgia and cerebellopontine-angle lipomas are very rare in children. We describe the history and findings of an 8-year-old boy with right trigeminal neuralgia and a lipoma detected by magnetic resonance imaging at the level of the root-entry zone of the right seventh cranial nerve. We propose a possible mechanism of infiltration of the trigeminal rootlets by the lipoma.
Epidemiological studies of cancer in aircrew.
2009
Exposure to cosmic ionising radiation, in addition to other specific occupational risks, is of concern to aircrew members. Epidemiological studies provide an objective way to assess the health of this occupational group. We systematically reviewed the epidemiological literature on health of aircrew members since 1990, focusing on cancer as the endpoint of interest. Sixty-five relevant publications were identified and reviewed. Whereas overall cancer incidence and mortality was generally lower than in the comparison population, consistently elevated risks were reported for breast cancer incidence in female aircrew members and for melanoma in both male and female aircrew members. Brain cancer…
Resection of C6 gliomas in rats with the aid of the waterjet technique
2016
While clinically the safety and efficacy of waterjet resection of brain tumors have been shown, evidence that waterjet dissection improves tumor resection radicality in comparison with conventional techniques is still missing. In the present study, resection radicality and tumor-free long-term survival of both techniques were evaluated in a C6-glioma model.Fifty-thousand C6-glioma cells were stereotactically transplanted in the left frontal lobe of 100 male Sprague-Dawley rats. After MRI-scanning for evaluation of tumor extension, microsurgical tumor resection was performed with conventional techniques (n=50) or with the waterjet dissector at pressures of 6bar (n=50). Twenty-five animals of…
Surgical treatment of posterior fossa tumors in infancy and childhood: techniques and results
1993
In a collective of 72 children with tumors of the posterior fossa, the preoperative diagnosis, operation planning and performance, and use of additional procedures, like the preliminary ventricular drainage and interventriculostomy are described. The extent of intra- and postoperative complications is given. Postoperative lethality was 0% in the group operated on between 1979 and 1991. The responsible factors are discussed. The findings support the opinion of ALBRIGHT (1989) that the prognosis for such patients is most promising in the hands of a specialist in pediatric neurosurgery.
Results from an international case-control study of childhood brain tumors: The role of prenatal vitamin supplementation
1998
An international case-control study of primary pediatric brain tumors included interviews with mothers of cases diagnosed from 1976 to 1994 and mothers of population controls. Data are available on maternal vitamin use during pregnancy for 1051 cases and 1919 controls from eight geographic areas in North America, Europe, and Israel. Although risk estimates varied by study center, combined results suggest that maternal supplementation for two trimesters may decrease risk of brain tumor (odds ratio [OR] 0.7, 95% confidence interval [CI] 0.5-0.9), with a trend of less risk with longer duration of use (p trend = 0.0007). The greatest risk reduction was among children diagnosed under 5 years of …
Correlation between EGFR Amplification and the Expression of MicroRNA-200c in Primary Glioblastoma Multiforme
2014
Extensive infiltration of the surrounding healthy brain tissue is a critical feature in glioblastoma. Several miRNAs have been related to gliomagenesis, some of them related with the EGFR pathway. We have evaluated whole-genome miRNA expression profiling associated with different EGFR amplification patterns, studied by fluorescence in situ hybridization in tissue microarrays, of 30 cases of primary glioblastoma multiforme, whose clinicopathological and immunohistochemical features have also been analyzed. MicroRNA-200c showed a very significant difference between tumors having or not EGFR amplification. This microRNA plays an important role in epithelial-mesenchymal transition, but its impl…
Neurinoma of the jugular foramen.
1990
The complementary predications of modern imaging techniques, CT, MRI and intraarterial digital subtraction angiography (i.a. DSA), in the differential diagnosis of a neurinoma of the jugular foramen are described.
The course of intracranial pressure and volume-pressure relationships following extirpation of meningiomas and astrocytomas
1978
Thirty-five patients with meningiomas were compared with 37 patients with astrocytomas with respect to the postoperative course of their ICP and elastance. In the case of the meningioma patients, the ICP increased on average over a longer period and achieved higher values than in the astrocytoma patients. In the first group, the elastance attained values that were three times as high as in the second group. There was no fixed relationship between pressure and elastance in the two groups of patients.