It Is essentialy diencephalon structure but anatomically situated at the diencephalo-mesencephalic junction at the level of the incisure of the cerebellar tentorium.

1. ANATOMY OF PINEAL GLAND
DR CHIRAG PANCHAL
SENIOR RESIDENT
DPT OF NEUROSURGERY

2. WHY PINEAL REGION ANATOMY
IS IMPORTANT FOR
NEUROSURGEONS?

3. • “Personally, I have never succeeded in
exposing pineal region tumor sufficiently
well to justify an attempt to remove it “
--- Cushing (1932)
• “Pineal tumors are perhaps the most
dangerous of all intracranial tumors to attack
surgically”
--- Walter Dandy

4. Introduction
• Latin “pinealis” -pine cone.
• epiphysis cerebri
• It Is essentialy diencephalon structure but
anatomically situated at the diencephalo-
mesencephalic junction at the level of the
incisure of the cerebellar tentorium.
• Extra-axial
• completely coated by the pia mater

5. Morphology and situation
• It is single, gray-brown- conical to oval
structure
• 6–10 mm in length
• 5–6 mm in width
• 1.5–4 mm in thickness
• weighs about 25 cg.

6. • upper part of pineal gland is in continuity with
the habenula, containing the little habenular
nucleus- also called anterior peduncle
• lower part is in continuity with the posterior
commissure.

7. Embryology
• derivated from two merged parts.
• At fourth week of life as a median evagination
of the caudal end of the diencephalon roof.
• Two pineal anlage develop at anterior neural
plate and fuse to form single organ

8. Embryology
• The cell proliferation of caudo-ventral part of the
diverticulum forming the first shape of the pineal
gland.
• Meningial structures cover the gland and enter
the gland architecture through which blood
vessel follw.
• reach its maximum size between the 5th or 7th
year of postnatal life
• Spongioblasts- become astrocytic glial cells.
• Penialoblast- defferentiate in to pinealocyte at 8
months

9. HISTOLOGY
• PINEALOCYTES -95%
Melatonin, Serotonin, Noeepinephrine,
Tryptophan
DMT – Di-methyl tryptamine
Blood and CSF
• PEPTIDERGIC NEURON LIKE CELLS.
• NEUROGLIA- ASTROCYTES.

10. PHYSIOLOGICAL FUNCTIONS
• CIRCADIAN RHYTHM-sleep cycle
Melatonin secretion stimulated in darkness
• Regulation of pitutary gland – sex hormones
inhibition-delay puberty

11. PINEAL REGION
• the pineal body inside the quadrigeminal
arachnoidal cistern
• posterior third ventricle,
• tectum,
• the complex of the great cerebral vein of
Galen,
• thalami
• splenium of corpus callosum

12. Relations

15. Relations

16. Relations
• Anteriorly related to base of third ventricle.
Posterior wall of third ventricle form from
superior to inferior by- pineal body, posterior
commissure and aqueduct of sylvius.
• Superiorly its related to tela choroidea of 3rd
ventricle,internal cerebral vein within velum
interpositum and fornix
• posteriorly it is related to splenium of the corpus
callosum, tentorial notch, vein of galen and
vermis

17. • Inferiorly it is related to superior and inferior
colliculi and aqueduct.
• Lateraly it is related to pulviar of thalamus,
tela choroidea, and splenium of corpus
callosum

18. Relationship to third ventricle
• Situated in the posterior wall of third ventricle
alog with habenular and posterior comissure.
• Ventro-caudaly lies opening of cerebral
aqueduct– compression by tumors lead to
“tri-ventricular” hydrocephalus
• Small evagination in to pineal body- pineal
recess

19. Relationship to Incisural space
• Distance between pineal gland and tentorial
notch varies from 10 to 30 mm.
• This variation influence the choice of whether or
not to perform a tentorial incision during a
surgical access of the region
• Along with tectum and lingula of vermis, it forms
the anterior wall of Incisural Space.
• quadrigeminal cistern, situated posterior to the
tectum plate, is the major cistern in the posterior
incisural space.

20. Vascular supply
• Lateral pineal artery
derived from the posteromedial choroidal artery
(PMCA branch of PCA) – main supply for pineal
gland
• Medial pineal artery
usually originates from the PMCA
• Rostral pineal artery
from the A5 segment of the ACA

25. Vascular supply
• Between 1 to 3 small pineal arteries penetrate
into the lateral wall of the pineal gland on
each side
• In one third of the cases, the arterial supply
originates only from one side.
• In addition to the pineal body, they supply the
superior and inferior colliculi and the
choroidal plexus of the third ventricle

26. • intrapineal vascular architecture has specific
features concerning the central part of the
pineal gland highly vascularized by large
sinusoid capillaries and its peripheral part
poorly vascularized by small and fine blood
vessels
• circumventricular organs

27. Venous drainage
• Pineal Vein-- originated from the habenular
trigone or from the junction between the
habenular trigone and the pineal body.
• Usualy drains directly to internal cerebral
veins or the vein of galen.

30. Veins of pineal region

31. Great cerebral vein of galen
• 5-25mm length (12mm)
• Single – midline
TRIBUTORIES
• Internal cerebral veins
• Basal veins of rosenthal
• Precentral cerebeller vein-- cerebellum, sup. Cerebeller
peduncle
• Internal occipital vein
• Pineal vein- penial body and habenular trigone
• Posterior pericallosal vein
DRAINS INTO
• Straight sinus

33. Internal cerebral vein
Tributeries-
• Anterio septal vein
• Thalamostriate vein
• Choroidal vein
Drains into
Vein of galen

36. Basal vein of rosenthal
Tributories
• Anterior cerebral vein
• Deep middle cerebral vein
• Striate vein
Drains in to
Vein of galen/ internal cerebral vein

38. Internal occipital vein
• Recieves blood from inferior and medial
portion of occipital lobe
• Drains in to vein of galen/internal cerebral
vein
Suerior vermian vein
• Arise from multiple small vein from culmen
• Drains in to vein of galen

40. • Posterior pericallosal vein
Arise from dorsal surface of corpus callosum
Drains in to internal cerebral vein
• Precentral cerebeller vein
Arise from precentral cerebeller fissure
Drains into internal cerebral vein

42. Thank you