THALAMUS
- THALAMUS ( चेतक )
- situation ( स्थान )
- lies above midbrain ( मध्यमस्तिष्क के ऊपर )
- one on each side of a slit like cavity called third ventricle
- shape and size( अकार )
- ovoid mass of grey matter
- 3.5 cm in length , 1.5 cm in breadth
- External features
- two ends ( दो छोर )
- anterior end ( अग्र )
- narrow
- constitutes tubercle of thalamus
- forms posterior boundary of interventricular foramen
- posterior end ( पश्च )
- expanded called pulvinar
- overhangs
- medial and lateral geniculate bodies
- superior colliculi with their brachia
- four surfaces
- superior surface
- lateral part
- forms floor of central part of lateral ventricle ( पार्श्व विलय )
- medial part
- covered by tela choroidea of 3rd ventricle
- inferior surface
- anterior part
- fused with sub-thalamus
- posterior part
- free
- inferior aspect of pulvinar
- medial surface
- greater part of lateral wall of third ventricle
- lateral surface
- medial boundary of posterior limb of internal capsule
- INTERNAL STRUCTURE
- MAINLY GREY MATTER
- divided by y shaped internal medullary lamina
- anterior
- tubercle
- lies between limbs of Y
- medial
- on medial side of stem of Y
- large Medial dorsal
- small medial ventral
- lateral
- on lateral side of stem of Y
- dorsal
- lateral dorsal
- lateral posterior
- large caudal nuclear mass
- pulvinar
- ventral
- ventral-lateral (ventral intermediate )
- ventral- anterior
- ventral - posterior
- ventral posterolateral
- ventral posteromedial
- other nuclei
- intralaminar nuclei
- midline ( paraventricular nuclei)
- reticular nucleus
- WHITE MATTER
- lateral surface of thalamus
- thin layer
- external medullary lamina
- superior surface
- stratum zonale
- inside thalamus
- internal medullary lamina
Discussion