REGIONAL CEREBRAL GLUCOSE CONSUMPTION MEASURED BY POSITRON EMISSION TOMOGRAPHY IN PATIENTS WITH UNILATERAL THALAMIC INFARCTION

Regional cerebral glucose consumption (rCMRGlc) was measured in 7 patients with unilateral and isolated thalamic infarctions and 19 normal subjects using F-18-fluorodeoxyglucose and positron emission tomography. Using X-ray computerized tomography and previously published templates, the TI were classified according to the vascular territories involved. Three of the thalamic infarctions were localized in the territory of the paramedian arteries, 2 in the territory of the inferolateral arteries, and 2 in that of the tuberothalamic artery. In 5 of the patients, a significant asymmetry of rCMRGlc remote to the thalamic lesion was detected involving the cerebellum and the caudate nucleus in 3 cases, the prefrontal cortex in 4 cases, and - in 3 cases each - the motor/premotor and the parietal cortex. No significant asymmetry of rCMRGlc was found in the occipital or temporal cortex in any of the patients studied. These data show that the remote metabolic depression consecutive to thalamic infarctions does not affect the whole cortical mantle uniformly, but in a more regionalized manner, which may be due to the selective interruption of distinct thalamocortical pathways.