Regional cerebral blood flow in patients with leuko-araiosis and atherosclerotic carotid artery disease.

The relation between white-matter lesions (WMLs), demonstrated with magnetic resonance imaging, and regional cerebral blood flow (CBF), measured with dynamic positron emission tomography and [18F] fluoromethane, was investigated in 20 patients with atherosclerotic disease of the internal carotid artery. There was no correlation between the extent of small patchy WMLs and hemispheric CBF, but hemispheric CBF was significantly reduced in 5 patients with multiple large or confluent lesions. Distinct focal cortical CBF reductions were observed when large WMLs (greater than 5 mm) were located directly beneath the cortex, whereas large WMLs in deeper white matter were associated with a more diffuse decrease of cortical perfusion.

Presentation of bilateral thalamic infarction on CT, MRI and PET.

Paramedian thalamic structures and part of the upper midbrain are frequently supplied by posterior thalamoperforating arteries originating from one common trunk. Local impairment of flow entails a bilateral more or less symmetric thalamic infarction with varying involvement of the midbrain. Diagnosis usually can neither be firmly established on clinical grounds nor by angiography alone.

Hypometabolic cortical lesions in tuberous sclerosis with epilepsy: demonstration by positron emission tomography.

Four patients with a well-established diagnosis of tuberous sclerosis and grand mal type epileptic seizures as their principal clinical symptom were examined by conventional surface electroencephalography (EEG), X-ray computed tomography, and positron emission tomography (PET) using the [18F]-2-fluoro-2-deoxyglucose method. The interictal EEG showed various abnormalities of poor localizing value, but no focal epileptic discharges. X-ray computed tomography demonstrated subependymal calcifications in all cases, although cortical lesions were found only twice.

Quantitative capillary topography and blood flow in the cerebral cortex of cats: an in vivo microscopic study.

In 50 anesthetized cats the microcirculation in intermediate and deeper layers of the cerebral cortex was visualized in vivo by microtransillumination, and documented by high-speed microcinephotography. The viability of the preparation was verified in a series of experiments demonstrating spontaneous vasomotion and responsiveness to chemical stimulation of pial arterioles and small arteries. Stereological methods for quantitative analysis of projected images of capillaries in a comparatively large tissue volume were employed to determine morphometric and topographical parameters of the asymmetric, highly tortuous intracortical capillary network.

Biochemical and histological effects of intermittent carbon monoxide exposure in cynomolgus monkeys (Macaca fascicularis) in relation to atherosclerosis.

The data in this report do not suggest any association between periodic carbon monoxide exposure and the development of atherosclerosis in cynomolgus monkeys. Animals were exposed to 200 to 400 ppm CO in the inspired air for 10 alternate half hours daily for approximately 12 months. These conclusions are reached from both histological and biochemical studies (aortic cholesterol content, arterial cholesterol influx, aortic oxygen consumption, as well as plasma triglyceride concentrations and HDL cholesterol to total cholesterol ratios).