BRS

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BRS Neuroanatomy

1. Tactile hypesthesia 2. Anesthesia 3. Hemiparesis (with Babinski sign)

4. Lower facial weakness 5. Homonymous hemianopia

B. Thalamic syndrome (Dejerine and Roussy) ■ usually caused by occlusion of a posterior thalamoperforating artery.

■ classic signs: contralateral hemiparesis; contralateral hemianesthesia; elevated pain threshold; spontaneous, agonizing, burning pain (hyperpathia); and athetotic posturing of the hand (tha lamic hand).

VIII. OVERVIEW: THE HYPOTHALAMUS

■ a division of the diencephalon. ■ lies within the floor and ventral part of the walls of the third ventricle. ■ functions primarily in the maintenance of homeostasis . ■ subserves three systems: the autonomic nervous system ( ANS ), the endocrine system , and the lim bic system .

IX. SURFACE ANATOMY OF THE HYPOTHALAMUS (See Figure 1.5)

■ visible only from the inferior aspect of the brain. ■ lies between the optic chiasm and the interpeduncular fossa (posterior perforated substance).

■ the hypothalamic sulcus forms superior border. ■ includes the following ventral surface structures :

A. Infundibulum

■ the stalk of the hypophysis. ■ contains the hypophyseal portal vessels. ■ contains the supraopticohypophyseal and tuberohypophyseal tracts. B. Tuber cinereum ■ the prominence between the infundibulum and the mammillary bodies. ■ includes the median eminence , which contains the arcuate nucleus .

C. Mammillary bodies ■ contain the mammillary nuclei.

D. Cerebral arterial circle (of Willis) ■ surrounds the inferior surface of the hypothalamus and provides its blood supply.

X. HYPOTHALAMIC REGIONS AND NUCLEI

Copyright © 2023 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. ■ the hypothalamus is divided into a lateral area and a medial area separated by the fornix and the mammillothalamic tract.

A. Lateral hypothalamic area ■ traversed by the medial forebrain bundle.