Intracranial metastasis of a spinal myxopapillary ependymoma. A case report.

A 37-year-old man exhibited a suprasellar tumor which histologically proved to be a myxopapillary ependymoma. Since these gliomas are virtually restricted to the cauda equina region, magnetic resonance imaging (MRI) was performed which revealed multiple spinal tumors. The present case seems to be the first report on spontaneous intracranial seeding of a spinal myxopapillary ependymoma.

High amino acid uptake in a low-grade desmoplastic infantile ganglioglioma in a 14-year-old patient.

Amino acid uptake is higher in high-grade than in low-grade gliomas; this is the rationale for using radioactively labelled amino acids for the non-invasive grading of brain neoplasms. We present a 14-year-old boy with a low-grade desmoplastic infantile ganglioglioma (DIG) that exhibited marked contrast enhancement on magnetic resonance imaging (MRI), but no signs of infiltration and only minimal surrounding edema. In this benign neoplasm the relative uptake of the radioactively labelled amino acid I-123-alpha-methyl tyrosine (IMT), determined using single-photon emission computed tomography (SPECT), was 3.

Diagnosis of recurrent glioma with SPECT and iodine-123-alpha-methyl tyrosine.

Unlabelled: Iodine-123-alpha-methyl tyrosine (IMT) allows the investigation of amino acid transport rate in brain neoplasms. It was the aim of this study to evaluate the potential of IMT-SPECT to diagnose the recurrence of gliomas after primary therapy.

Methods: Using a triple-headed SPECT camera, the cerebral uptake of IMT was determined in 27 patients 22 mo, on average, after surgical removal of a primary brain tumor.

Iodine-123-alpha-methyl tyrosine in gliomas: correlation with cellular density and proliferative activity.

Unlabelled: Amino acid transport rate in gliomas can be assessed using SPECT and the amino acid L-123I-alpha-methyl tyrosine (IMT). This study attempted to correlate the uptake of IMT by gliomas with the proliferative activity and cellular density of these neoplasms.

Methods: The study used 27 patients with gliomas, including 18 patients with high-grade tumors and nine patients with low-grade neoplasms.

Non-invasive grading of primary brain tumours: results of a comparative study between SPET with 123I-alpha-methyl tyrosine and PET with 18F-deoxyglucose.

Use of iodine-123-alpha-methyl tyrosine (123I-IMT) allows investigation of the amino acid transport rate in gliomas. It was the aim of this study to compare the value of measurement of glucose metabolism with that of measurement of 123I-IMT uptake for the non-invasive grading of brain tumours. The study population comprised 23 patients with histopathologically proven primary brain tumours; 14 had high-grade gliomas, and nine low-grade brain neoplasms.

Shifts of cortical d.c. potential induced by application of gamma-aminobutyric acid in rats in vivo.

Generally, increases in cortical activity go in parallel with negative shifts and decreases with positive shifts of cortical d.c. potentials.

Uptake of iodine-123-alpha-methyl tyrosine by gliomas and non-neoplastic brain lesions.

Using single-photon emission tomography (SPET), the radiopharmaceutical l-3-iodine-123-alpha-methyl tyrosine (IMT) has been applied to the imaging of amino acid transport into brain tumours. It was the aim of this study to investigate whether IMT SPET is capable of differentiating between high-grade gliomas, low-grade gliomas and non-neoplastic brain lesions. To this end, IMT uptake was determined in 53 patients using the triple-headed SPET camera MULTISPECT 3.

Repetitive hypoxic exposure of brain slices and electrophysiological responses as an experimental model for investigation of cerebroprotective measurements.

An in vitro hippocampal (CA 1 region, guinea pig) slice technique using repeated hypoxia was employed to model electrophysiological changes (DC-potentials and evoked potentials (EP) by stimulation of Schaffer-collaterals) occurring in the hypoxic CA1 pyramidal layer. A standardized neuronal response under repeated hypoxic conditions was observed in this model, consisting of disappearance of EP and a trend towards partially reversible, but progressive synaptic failure subsequent anoxic depolarisation (AD). Slices treated with the calcium antagonist nimodipine showed a prolongation of AD latency between the first and following hypoxias.

Influence of size of regions of interest on the measurement of uptake of 123I-alpha-methyl tyrosine by brain tumours.

The aim of this study was to assess the influence of variations in the size of regions of interest (ROIs) on uptake values in brain tumours of L-3-iodine-123-alpha-methyl tyrosine (IMT). In addition, we attempted to establish the influence of size of ROIs on levels of significance assessing differences in mean IMT uptake between high-grade and low-grade tumours. Relative IMT uptake was determined in 19 patients with brain tumours using a MULTISPECT 3 triple-headed camera.