Special Thanx to Nishna Bharathan(2007-2011)optometry batch Alsalama College Of Optometry,Perinthalmanna)

3. CHOROID
 Post part of vascular coat
 Extends from optic disc to ora serrata
 Inner surface is smooth, brown& lies contact with RPE
 Outer surface is rough &contact with sclera

5. MICROSCOPIC STRUCTURE
 3 LAYERS
 Supra choroidal lamina
 Stroma of the choroid
 Basal lamina

7.  Supra choroidal lamina :
 Thin memb of condensed collagen fibres ,
melanocytes &fibroblast
 Continuous ant with supraciliary lamina
 The potential space B/W this memb & sclera is called
suprachoroidal space
 Which contain long & short post ciliary arteries &
nerve

8.  Stroma of the choroid :
 Loose collagenous tissue with elastic & reticular fibres
 Contain pigments & plasma cells
 Main bulk is formed by vessels -3 layers
 -layer of large vessels (haller`s layer)
 -layer of medium vessels (sattler`s layer)
 -layer of choriocapillaries –nourishes the outer layers of
the retina

9.  Basal lamina
 Also called Bruch's memb& lines the layer of
choriocapillaries
 Lies with RPE
 5 layers-basement memb of rpe
 Inner collagen layer
 Middle elastic layer
 Outer collagen layer
 Basement memb of choriocapillaries

10. BLOOD SUPPLY TO THE UVEAL TRACT
 3 ARTERIAL SUPPLY:
 Short post ciliary arteries
 Long post ciliary arteries
 Ant ciliary arteries

11.  Short post ciliary arteries
 Arise as 2 trunk from ophthalmic arteries
 Divide 10-20 branch which pierce in sclera around
optic nerve & supply choroid

12.  Long post ciliary artery:
 2 –nasal &temporal
 Pierce sclera obliquely on medial &lateral side of optic
nerve & run forward in supra choroidal space to reach
ciliary muscle

13.  Ant ciliary arteries
 Derived from ophthalmic artery
 7 in no: 2 from SR,IR,MR &1 from LR
 These pass ant to episclera , give branch to sclera,limbus&
conju
 Pierce sclera near limbus to enter ciliary muscle
 Anastomose with 2 LPCA form-circulus arteriosus major-
near root of iris

15.  Venous drainage:
 Ant ciliary veins
 Smaller veins from sclera
 The venae verticosae (post ciliary veins)

16.  1)-are tributaries of muscular vein
 Since Carry blood only from ciliary muscle-small
arteries
 2)-Carry blood only from sclera & not from choroid-
smaller than arteries
 Correspond to short ciliary arteries

17.  3) 4 in no: S & I temporal S &I nasal
 Pierce sclera obliquely on each side of SR& IR muscles
 Drain blood from whole of choroid
 Small vein from optic nerve head, retina also
 Tributaries from iris ,ciliary process, ciliary muscle, ant
choroid
 4 veins converge at apex of orbit
 2 sup vortex vein open to S ophthalmic vein& I VV to I
ophthalmic vein

18. PHYSIOLOGICAL CONSIDERATIONS
 1- It is the source of blood flow to the ocular tissues
 2 - Site of aq humor production &maintain IOP
 3 - Constitute blood aq barrier
 4 -Musculature of the ciliary body play role in process
of accommodation
 5 - Eicosanoids are synthesized in iris & ciliary body
 6 - Play role in detoxification & antioxidation in ant
segment

19.  Eicosanoids in iris & ciliary body
 Is generic term to describe prostaglandins &
leukoterienes
 Both are metabolites of arachidonic acid
 Prostaglandins synthesized in great amt after trauma
or inflammation of iris , ciliary body from arachidonic
acid released by esterified site in phospholipid memb)

20.  Many other peptides are present in iris, CB & aq
including neuropeptide, y calcitonine gene related
peptide- CGRP
 Cyclo-oxy pathway in microsomes
 many of the peptide modulate Normal function –
PGE2- miosis & PGF2alpha- control iop by AQ
production
 CGRP RELAXES;Iris dialator
 Also have immunosuppressive role

21. Detoxification &anti oxidation in the ant seg
 The cytochrome p 450 system is the major drug
detoxification in the eye
 -microsomes contain a group of protein –cp450-
catalyze transfer of a single o2 atom to exogenous or
endogenous substance for detoxification
 Convert hydrohpobic to hydrophillic compounds
 Highly reactive comp by conju to glutathione
 Most enzyme invoved detoxification process –in CB

22. The ciliary body is the main source of antioxident
system in the ant seg
 Exist in cornea, lens CB is rich in antioxidant with
high conc of catalase ,superoxide dismutase&
glutothionine peroxidates type i & type ii
 Type I selanine dependent – reduction of oxydised
glutathionine,by detoxification of peroxides
 Type ii selanine independent

23. THANK YOU