Download PONS - Yengage

FOURTH VENTRICLE
By
Dr Shivarama Bhat P
VENTRICLES
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•
•
•
2 Lateral Ventricles.
Third ventricle.
Fourth ventricle.
Terminal ventricle.
VENTRICLES
VENTRICLES
FOURTH VENTRICLE
The Fourth Ventricle
(ventriculus quartus)
Cavity of the hind-brain is situated in
• front of the cerebellum and
• behind the pons and
• behind upper half of the medulla
oblongata.
FOURTH VENTRICLE PARTS
• Roof (dorsal wall)
• Floor (ventral wall)
• Lateral
boundaries
• Four angles
FOURTH VENTRICLE
LATERAL BOUNDARIES
• Upper Part:-superior peduncle
middle peduncle
• Lower Part:–
inferior peduncle
fasciculus cuneatus
fasiculus gracilis
FOURTH VENTRICLE
Floor -RHOMBOID FOSSA
Locus cerulus
Vestibular area
Facial colliculus
Hypoglossal triangle
Median sulcus
Sulcus limitans
Median eminence
Superior fovea
Striae medullaris
Inferior fovea
Vagal triangle
Area postrema
FOURTH VENTRICLE
DORSAL WALL
Upper Portion of the roof
• superior peduncle
• superior medullary velum
Lower Portion
• inferior medullary velum
Inferiorly
• tæniæ of the fourth ventricle
FOURTH VENTRICLE
FOURTH VENTRICLE
ROOF
RECESSES
FOURTH VENTRICLE
ROOF
Three openings, a median and two lateral:
• 1 median aperture (foramen Magendii),
• 2 lateral apertures (foramina of Luschka)
By means of these three openings the
ventricle communicates with the
subarachnoid cavity
FOURTH VENTRICLE
ANGLES
• Superior angle
• Inferior angle
• Two lateral angle
CHOROID PLEXUSES
• Highly vascular inflexions of the tela
chorioidea
• Invaginate the lower part of the roof of
the ventricle
• Each consists of a vertical and a
horizontal portion
• The structure presents the form of the
letter T, the vertical limb being double
HYDROCEPHALUS
Questions
• 4th ventricle – Long essay.
• Enumerate the connections of 4th ventricle –
Short answer.
• Floor of 4th ventricle – Short essay.
• Roof of 4th ventricle – Short essay.