[Magnetic resonance tomographic diagnosis of vascular processes in the vertebrobasilar system--analysis of 35 of our own cases and a literature review]. / Kernspintomographische Diagnostik von Gefässprozessen im vertebrobasilären Stromgebiet--Analyse von 35 eigenen Beobachtungen und Literaturübersicht.

35 patients with abnormalities of the vertebrobasilar system were studied via magnetic resonance imaging (11 saccular aneurysms, 10 vascular malformations, 9 basilar arteries with dolichoectasia, 5 thromboses of the vertebral or basilar artery). The two smallest aneurysms of the basilar top had a diameter of 2-3 mm. Most vascular malformations could be differentiated by typical MRT symptoms. All 5 cavernous angiomas were negative in angiography (cryptic). The shape and size of the basilar artery and its relationship to the third ventricle were best demonstrated on coronal slices. Flow-related intraluminal loss of signal allows a differentiation between vascular perfusion and thrombosis already on plain images (partial) thrombosis and artery dissection can be differentiated from flow effects based on identical findings in at least two planes or additional gradient echo images.

[Follow-up and prognosis of herpes simplex encephalitis. Observations on 57 patients between 1960 and 1987]. / Verlauf und Prognose der Herpes-simplex-Enzephalitis. Beobachtungen an 57 Patienten zwischen 1960 und 1987.

A retrospective study of outcome in 57 herpes simplex encephalitis (HSE) patients treated between 1960 and 1987 is reported. HSE was confirmed by virus isolation or detection of intrathecal anti HSV synthesis. 24 patients did not receive antiviral therapy, 19 were vidarabine recipients and 14 were treated with acyclovir. Mortality was not correlated with sex or age but with the level of consciousness at onset of therapy. Acyclovir therapy was by far superior to vidarabine with respect both to mortality and neurologic sequelae after a mean follow-up period of 170 days.

Effect of piracetam on cerebral glucose metabolism in Alzheimer's disease as measured by positron emission tomography.

The effect of piracetam (a putative enhancer of cerebral metabolism) on regional CMRGlu was studied by positron emission tomography of 2[18F]-fluoro-2-deoxy-D-glucose in nine patients with Alzheimer's disease, and in seven cases with multiinfarct dementia or unclassified dementia. In Alzheimer's disease, i.v. administration of piracetam, 6 g b.i.d. for 2 weeks, significantly improved rCMRGlu in most cortical areas, whereas no effect on CMRGlu of the drug was observed in the multiinfarct dementia/unclassified dementia groups. These results lend further support to the notion that adjuvant piracetam treatment is of benefit in Alzheimer's disease. They may also indicate that the typical metabolic depression in Alzheimer's disease is caused by complex interaction of disturbed transmitter and cellular function rather than by a specific deficit in the cholinergic system alone.

Uncoupling of hexose transport and phosphorylation in human gliomas demonstrated by PET.

Tumor uptake of [18F]2-fluoro-2-deoxy-glucose (FDG) was studied in 20 patients with histologically classified gliomas, using dynamic positron emission tomography (PET). Parametric images of local blood volume, glucose metabolic rate, transport and phosphorylation rate constants were generated by weighted non-linear least-squares fits on a pixel-by-pixel basis. Tumor metabolism, i.e. ratios of tumor peak metabolism to contralateral brain metabolism, corresponded with histological grade. Approximately half of the tumors showed considerable metabolic heterogeneity, and metabolically active areas were found in the periphery of seven tumors. Rate constants of FDG transport and phosphorylation were significantly correlated and were inversely coupled to plasma glucose levels in contralateral brain. In contrast, tumor transport and phosphorylation rate constants varied independently of each other and of plasma glucose concentration. In some tumors large alterations of FDG phosphorylation were observed in presence of nearly normal FDG transport.