![]() There are 4 major thalamic vascular territories, each with a predilection for supplying particular groups of nuclei. 12 The subject was reevaluated by Percheron, 13–17 and subsequent reports helped to simplify the clinical-anatomic considerations. The details of thalamic vascularization were first studied by Duret 9 and Foix and Hillemand 10 and subsequently by Lazorthes 11 and Plets et al. Thalamic Blood Supply and Vascular Syndromes This article reviews the vascular syndromes resulting from thalamic lesions and uses these clinical manifestations along with connectional studies in monkeys to formulate putative functional attributes of the thalamic nuclei. More precise anatomic-clinical correlations have been derived from studies of thalamic stroke. 8 Conclusions concerning thalamic functions in humans have also been derived from thalamotomy and thalamic stimulation studies (referred to below) and more recently from functional imaging studies that fall outside the scope of this review. A patient with a penetrating injury of the left thalamus (intralaminar, dorsomedial, ventral lateral, and ventral anterior nuclei and mamillothalamic tract) developed amnesia for verbal material, but the lesion also involved the posterior hypothalamus and both mamillary bodies. Similarly, accounts of deficits in adults 6 and children 7 with thalamic tumors have helped to shape the understanding of the behavioral manifestations of thalamic lesions, but the structure-function analysis is too complex to establish with certainty that the behavior is a consequence of involvement of the thalamus alone. 2–5 Hemorrhage is seldom confined to the thalamus itself, however, and remote effects include pressure of the hemorrhagic mass, effect of surrounding edema on adjacent structures, and toxic effects of the blood products. Later reports of thalamic hemorrhage confirmed and extended the relationship between thalamic lesions and cognitive deficits. Sensory deficits were associated with neglect (“modified anosognosia and hemiasomatognosia”), “dysphasia” was global and moderate in severity, and confusion, delirium, visual hallucinations, and peduncular hallucinosis taking the form of colorful objects, animals, and flowers were described. In the first detailed account of the behavioral consequences of thalamic hemorrhage, Fisher 1 described 13 patients of a total of 102 cases of intracerebral hemorrhage pathologically studied. Posterior choroidal lesions result in visual field deficits, variable sensory loss, weakness, dystonia, tremors, and occasionally amnesia and language impairment.Ĭonclusions- These vascular syndromes reflect the reciprocal cerebral cortical-thalamic connections that have been interrupted and provide insights into the functional properties of the thalamus. Inferolateral territory strokes produce contralateral hemisensory loss, hemiparesis and hemiataxia, and pain syndromes that are more common after right thalamic lesions. Right thalamic lesions in both these vascular territories produce visual-spatial deficits, including hemispatial neglect. Language deficits result from left paramedian lesions and from left tuberothalamic lesions that include the ventrolateral nucleus. ![]() Autobiographical memory impairment and executive failure result from lesions in either of these vascular territories. Paramedian infarcts cause decreased arousal, particularly if the lesion is bilateral, and impaired learning and memory. Tuberothalamic territory strokes produce impairments of arousal and orientation, learning and memory, personality, and executive function superimposition of temporally unrelated information and emotional facial paresis. Vascular lesions destroy these nuclei in different combinations and produce sensorimotor and behavioral syndromes depending on which nuclei are involved. Summary of Review- Thalamic nuclei are composed of 5 major functional classes: reticular and intralaminar nuclei that subserve arousal and nociception sensory nuclei in all major domains effector nuclei concerned with motor function and aspects of language associative nuclei that participate in high-level cognitive functions and limbic nuclei concerned with mood and motivation. Customer Service and Ordering Informationīackground- This article reviews the anatomy, connections, and functions of the thalamic nuclei, their vascular supply, and the clinical syndromes that result from thalamic infarction.Stroke: Vascular and Interventional Neurology.Journal of the American Heart Association (JAHA).Circ: Cardiovascular Quality & Outcomes.Arteriosclerosis, Thrombosis, and Vascular Biology (ATVB).
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