Ciliary Body

Question 1

What is Ciliary Body

Answer 1

Highly vascular and pigmented structure with special involvement in-
Accommodation
Production of aqueous
Production of Vitreous Constiuents
-Anterior border marked by scleral spur
-posterior border marked by ora serrata

Question 2

Structure

Answer 2

Anterior part has many ridges- Pars Plicata
Further back posterior part is flat- Pars Plana
Suspensory fibres(zonular fibres) of lens run from pars plana pass through ciliary processes of pars plicate and attach to lens capsule

Question 3

Supracilliaris -1

Answer 3

Transition zones from CB stroma to sclera
Lines sclera from scleral spur to choroid with which it blends posteriorly with choroid
Consists of collagen interlaced with fibroblast and melanocytes which are pigmented unlike ones in sclera

Question 4

Stroma- 2

Answer 4

Bulk of stroma filled with ciliary muscle. Muscle is anterior attached at scleral spur and fibres posteriorly into stroma of choroid.
Ciliary muscle fibres are split into 3 groups based on their orientation= longitudinal fibres, radial , circular fibres
- Contraction of ciliary muscle releases tension on zonular fibres and allows lens to take up its accommodated form.

Question 5

Epithelium- 3

Answer 5

Double layer - inner layer pigmented- one closes to ciliary muscle
outer layer unpigmented - the opposite of iris
Unpigmented cells in pars plicata- contain many mitochondria(metabolically active) and RER (involved in protein synthesis)
Unpigmented cells in pars plana- many RER but fewer mitochondria Unpigmented layer produces aqueous
Cells along ridges of ciliary processes contain large amounts of glycogen - intermediate energy source this is metabolic reactions of tissue.

Question 6

Blood supply

Answer 6

MAC is in ciliary body near its attachment to root of iris
Supply comes from anterior ciliary artery vessels passing within ciliary plexus then passing backwards and draining into the choroidal system.

Question 7

Nerve Supply

Answer 7

Autonomic parasympathetic nerve fibres are found in supraciliaris and stroma en route to iris producing miosi and some in CB produce accommodation
Autonomic Sympathetic nerve fibres are found and some travel to iris producing mydriasis, whilst those that terminate in CB may produce vasoconstriction.