Publications by authors named "H L Lagreze"

Progressive leukoencephalopathy developed in a patient with adult celiac disease. Neurologic abnormalities appeared 4 years after the gastrointestinal manifestations despite a gluten-free diet and replacement of vitamins. Brain MRI showed marked confluent white matter abnormalities, and stereotactic brain biopsy revealed chronic leukoencephalopathy.

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With respect to the methodology of the atraumatic Xenon-133 technique the problem whether or not the proposed and introduced arterial artifact (AA) truely represents radiation from intravascular volume and to what extent it affects regional cerebral blood flow (rCBF) calculation is unresolved. We performed rCBF measurements in 22 patients with angiomas to clarify this issue in those patients known to have pathologically enlarged intracranial vessels. P4--the parameter suggested to represent the AA--as well as the conventional blood flow parameter for gray matter (F1) were compared to those of 50 volunteers using four criteria of abnormality: 1.

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Background And Purpose: Three mainstream strategies exist to detect the responses of regional cerebral blood flow to functional activation. We tested the significance of changes in raw regional cerebral blood flow data, regional cerebral blood flow data normalized by division by global cerebral blood flow (dependent model of the regional-to-global cerebral blood flow relation), and regional cerebral blood flow data treating global cerebral blood flow as a covariate (independent model). Both latter models attempt to enhance regional sensitivity by removing global effects.

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To explore the integration of functional neuronal interactions in human higher cortical functions, we applied multivariate mathematical techniques to regional cerebral blood flow (rCBF) increases induced by mental activity. rCBF was measured using the intravenous xenon-133 clearance technique with 32 bihemispheric detectors in 84 normal volunteers at rest and during both a visuoperceptual accuracy task and a visuospatial problem solving task. Both paradigms activated rCBF in bilateral premotor, motor and postcentral regions.

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