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  • Proton magnetic resonance spectroscopy  (2)
  • Arachnoid (cyst, granulation)  (1)
  • CT  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Acta neurochirurgica 139 (1997), S. 349-354 
    ISSN: 0942-0940
    Keywords: Arachnoid (cyst, granulation) ; meningioma ; progesterone receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We report 2 cases of arachnoid cysts, one with a retrocerebellar and the other with a left temporal localization, in which immunohistochemical studies had been conducted. The results of the immunohistochemistry on the presence of carcino-embryonic antigen (CEA) and glial fibrillary acidic protein (GFAP), and of the scanning- and transmission electron microscopy revealed the cyst lining to be identical to subdural neurothelium. Progesterone receptors were found in the nuclei of cells lining the cyst, which also suggests the similarity of the cyst lining to arachnoid granulations and meningiomas as derivatives of subdural neurothelium, which also possess progesterone receptors.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Acta neurochirurgica 125 (1993), S. 41-46 
    ISSN: 0942-0940
    Keywords: Brain oedema ; meningioma ; CT ; MRI
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary There is a great variability in the amount of peritumoural brain oedema accompanying meningiomas. In a previous study it was found that the degree of brain oedema in the white matter around meningiomas correlated with disruption of the layers (especially the cerebral cortex), which separate the tumour from the white matter, as well as with the size and histological subtype of the tumour. In the present study comprising 9 meningiomas, the volume of oedema was calculated by integration of the cross-sectional oedematous areas on serial MRI slices. The volume of oedema was zero in 3 cases and ranged from 11 to 176.4 ml in the other 6 cases. The MRI-scans also showed disruption of the cortex in all cases, ranging from slight to severe. T1 and T2 measurements were made at the level of maximum extension, using a mixed sequence at a field strength of 1.5 T. From the T2 values tissue water content in % was calculated using the equations: WC=39.36/(R2 + 37.2) for cortex, and WC=29.63/(R2 + 27.8) for white matter. These had been obtained by correlating water content with relaxation rates, measured in vitro on human brain autopsy specimens which were subjected to hydration with distilled water or dehydration by hyperosmolar solutions. Mean water content amounted to 82.53% for normal cortex, 74.72% for normal white matter, and 84.59% for oedematous white matter around the tumour. On the assumption that the spread of contrast agent marks the advancement of the front of oedema produced by the tumour, CT-studies were made before, and at 1 1/2, 3 and 6h after contrast infusion. The increase in diameter of the contrast-stained area on the CT-scan allows calculation of the excess of oedema production per unit tumour volume. Of 6 tumours with oedema (mean peritumoural water content of 91% and mean volume of oedema of 69.2 ml) the production excess at the steady-state was 0.18–1.08 ml/h/cm3 tumour volume, whereas 3 tumours without associated oedema had a production excess of 0.03–0.12 ml/h/cm3. Moreover, penetration of the cortex seems to constitute a separate factor determinig the spread of oedema.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-1920
    Keywords: Gliomas ; Proton magnetic resonance spectroscopy ; Proton magnetic resonance spectroscopic imaging ; Brain oedema ; Positron emission tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In 32 patients with gliomas, one- and two-dimensional proton magnetic resonance spectroscopy (1H-MRS) has been conducted, the latter allowing reconstruction of spectroscopic data into a spectroscopic image (MRSI), showing the distribution of the various metabolite concentrations over the cross-sectional plane. For lack of absolute concentrations, the measured concentrations of phosphocholine (CHOL),N-acetyl-L-aspartate (NAA), and lactate (LAC) were conventionally expressed in ratios relative to that of creatine (CREAT). Compared to normal brain tissue, an increased CHOL/CREAT ratio was found in all groups of tumours, in glioblastomas, high-, middle- and low-grade astrocytomas both at the margin and the core of the tumours, but in oligodendrogliomas only at the margin. This is consistent with an increased phosphocholine turnover in relation to membrane biosynthesis by the proliferating cells. The NAA/CREAT ratio was decreased in all groups of tumours, both in the centre and at the margin, reflecting replacement of functioning neurons by neoplastic cells. The LAC/ CREAT ratio was elevated in the core of malignant gliomas, which may be the result of a prevailing glycolysis, characteristic of tumours, possibly in conjunction with hypoxia/ischaemia. In the perifocal oedema, there was neither elevation of the CHOL/CREAT ratio nor decrease of the NAA/CREAT ratio; an increased LAC/CREAT ratio therefore rather reflected ischaemia/hypoxia probably due to locally elevated pressure and compromised regional perfusion. In the normal brain, the metabolite ratios of grey matter did not differ from those of white matter. The frontal lobe and basal ganglia showed lower NAA/CREAT ratios than the other cerebral areas. In 7 patients positron emission tomography was also performed with [18F]fluoro-2-deoxy-D-glucose (18FDG) or L-[1-11C]-tyrosine (11C-TYR); the latter demonstrated a pattern of11C-TYR uptake similar to that of CHOL elevation in the MRSI.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-1920
    Keywords: Key words Gliomas ; Proton magnetic resonance spectroscopy ; Proton magnetic resonance spectroscopic imaging ; Brain oedema ; Positron emission tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In 32 patients with gliomas, one- and two-dimensional proton magnetic resonance spectroscopy (1H-MRS) has been conducted, the latter allowing reconstruction of spectroscopic data into a spectroscopic image (MRSI), showing the distribution of the various metabolite concentrations over the cross-sectional plane. For lack of absolute concentrations, the measured concentrations of phosphocholine (CHOL), N -acetyl-L-aspartate (NAA), and lactate (LAC) were conventionally expressed in ratios relative to that of creatine (CREAT). Compared to normal brain tissue, an increased CHOL/CREAT ratio was found in all groups of tumours, in glioblastomas, high-, middle- and low-grade astrocytomas both at the margin and the core of the tumours, but in oligodendrogliomas only at the margin. This is consistent with an increased phosphocholine turnover in relation to membrane biosynthesis by the proliferating cells. The NAA/CREAT ratio was decreased in all groups of tumours, both in the centre and at the margin, reflecting replacement of functioning neurons by neoplastic cells. The LAC/CREAT ratio was elevated in the core of malignant gliomas, which may be the result of a prevailing glycolysis, characteristic of tumours, possibly in conjunction with hypoxia/ischaemia. In the perifocal oedema, there was neither elevation of the CHOL/CREAT ratio nor decrease of the NAA/CREAT ratio; an increased LAC/CREAT ratio therefore rather reflected ischaemia/hypoxia probably due to locally elevated pressure and compromised regional perfusion. In the normal brain, the metabolite ratios of grey matter did not differ from those of white matter. The frontal lobe and basal ganglia showed lower NAA/CREAT ratios than the other cerebral areas. In 7 patients positron emission tomography was also performed with [18F]fluoro-2-deoxy-D-glucose (18FDG) or L-[1-11C]-tyrosine (11C-TYR); the latter demonstrated a pattern of 11C-TYR uptake similar to that of CHOL elevation in the MRSI.
    Type of Medium: Electronic Resource
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