Lecture 7: Ciliary Body
a
positive accommodation a) parasympathetic b) sympathetic
b
relaxation of accommodation a) parasympathetic b) sympathetic
Ciliary Body
responsible for: • Secretion - Aqueous humour - Zonular fibres - Vitreous hyaluronic acid • Accommodation • Anchors the zonular fibres
Ciliary Body Melanoma
- 4-8 cases per 1 million people. - Represent about 10% of intraocular melanomas Risk Factors: -sunlight exposure -age -race -iris colour.
posterior ciliary body, outer ciliary body
Blood Supply: The intramuscular circle primarily supplies what?
ciliary processes
Blood Supply: The major arterial circle of the iris primarily supplies what?
Major arterial circle of iris
Blood Supply: What primarily supplies the ciliary processes?
Intramuscular circle
Blood Supply: What primarily supplies the posterior and outer ciliary body?
b
Dentate processes/retinal teeth are located where? a) pars plicata b) pars plana
Neuroectoderm
Development/Embyology: Ciliary epithelial lining (NPE/PE) form from what? Represent the two layers of the optic cup.
Mesenchyme (mesoderm + neural crest cells)
Development/Embyology: Ciliary stroma and muscle form from what? At edge of optic cup, anterior continuation of the choroid.
b
Edinger-Westphal nucleus (in brain stem), oculomotor nerve, ciliary ganglion, short posterior ciliary nerves This is the neural pathway of what innervation? a) sympathetic b) parasympathetic c) sensory
Leaky
Fenestrated Capillaries in the Ciliary Processes are what?
16
Giant senate processes are not present in all eyes, what percentage of eyes have giant senate processes? in %
Parasympathetic
Innervation: Carried along oculomotor nerve, ciliary ganglion, short posterior ciliary nerves Results in positive accommodation
Sympathetic
Innervation: From Cervical sympathetic trunk (spine), superior cervical ganglion, via long ciliary nerves. relaxation of accommodation
Sensory fibres
Innervation: Nasociliary branch of ophthalmic division of trigeminal, long ciliary nerves
b
Insertion of ciliary muscle tendons, elastic attachment to anterior choroid & Bruch's membrane a) anterior insertion b) posterior insertion
long ciliary nerves
Name the nerve of the sensory pathway that enters the ciliary muscle.
long ciliary nerve
Name the nerve of the sympathetic pathway that enters the ciliary muscle.
b
Origin of zonules a) pars plicata b) pars plana
b
Origin of zonules is the a) Pars Plicata (corona ciliaris) b) Pars Plana (orbicularis ciliaris)
a
The non-pigmented epithelium of the ciliary body is in the... a) inner layer (towards the centre of the eye) b) outer layer (towards the surface of the eye)
Melanosomes
The outer pigmented epithelium of the ciliary body contain what?
Edinger-Westphal nucleus
The parasympathetic innervation of the ciliary muscle is carried along the oculormotor nerve which originated from?
oculomotor nerve
The parasympathetic innervation of the ciliary muscle originates at what nerve?
a
Valleys between ciliary processes are present at? a) pars plicata b) pars plana
a
Very vascular a) pars plicata b) pars plana
Major arterial circle of iris
What structure is C? Primarily supplies ciliary processes.
Canal of Schlemm (scleral venous sinus)
What structure is D?
Desmosome
What structure is D?
Iris
What structure is D?
anterior chamber
What structure is D?
basement membrane
What structure is D?
ciliary muscle
What structure is D?
long posterior ciliary artery
What structure is D?
pupil
What structure is D?
trabecular meshwork
What structure is D?
Canal of Schlemm
What structure is E?
Ciliary stroma
What structure is E?
ciliary process
What structure is E?
conjunctiva
What structure is E?
edge of pupil
What structure is E?
iris
What structure is E?
storm of ciliary body
What structure is E?
Pars plicata
What structure is F?
cornea
What structure is F?
corneal epithelium
What structure is F?
fenestrated capillary epithelium
What structure is F?
iris
What structure is F?
pupil
What structure is F?
Epithelium
What structure is G?
Lens
What structure is G?
anterior limiting lamina
What structure is G?
blood vessel of ciliary body
What structure is G?
ciliary body
What structure is G?
limbus
What structure is G?
corneal stroma (substantia propria)
What structure is H?
neural part of the retina
What structure is H?
nonpigmented epithelium
What structure is H?
sclera
What structure is H?
vitreous chamber
What structure is H?
Outer longitudinal fibres/ meridional fibres/ Brücke's muscle
What structure is I?
ora serrata
What structure is I?
pigmented epithelium
What structure is I?
posterior limiting lamina
What structure is I?
crypt
What structure is J?
oblique fibres of ciliary muscle/ radial fibres of ciliary muscle
What structure is J?
pars plana
What structure is J?
Bruch's membrane
What structure is K?
ciliary processes
What structure is K?
pigment layer
What structure is K?
lens capsule
What structure is L?
lens nucleus
What structure is M?
zonule
What structure is N?
trabecular meshwork
What structure is O?
ciliary epithelium
What structure is P?
cysts at ora serrata
What structure is Q?
major ciliary processes
What structure is a?
intermediate processes
What structure is b?
pars plana
What structure is c?
scalloped bays
What structure is d?
dentate processes
What structure is e?
striate, linear markings
What structure is f?
valleys
Where are the minor ciliary processes located in?
a
Which ciliary muscle tendon assists aqueous drainage? a) anterior insertion b) posterior insertion
a
Which epithelial layer contains infoldings? a) Inner non-pigmented epithelium b) outer pigmented epithelium
b
Which epithelial layer contains melanosomes? a) Inner non-pigmented epithelium b) outer pigmented epithelium
a
Which epithelial layer contains secretory granules? a) Inner non-pigmented epithelium b) outer pigmented epithelium
b
Which epithelial layer is the extension of the retinal pigment epithelium? a) Inner non-pigmented epithelium b) outer pigmented epithelium
b
Which epithelial layer junctions? a) Inner non-pigmented epithelium b) outer pigmented epithelium
a
Which includes the ciliary muscle? a) pars plicata b) pars plana
a
Which is continuous with neural retina a) Inner non-pigmented epithelium b) outer pigmented epithelium
a
Which is true regarding the epithelial cells of the outer pigmented epithelium of the ciliary body? a) cells case base face out towards the surface of eye, apices face in b) cells case base face in towards the centre of eye, apices face out
lens
What structure is C?
nonpigmented epithelium
What structure is C?
pigmented epithelium
What structure is C?
tight junction
What structure is C?
trabecular meshwork
What structure is C?
unpigmented epithelium
What structure is C?
a
- Type 1 from outer longitudinal muscle into sclera or scleral spur. a) anterior insertion b) posterior insertion
b
Age changes to ciliary body: Amount of muscle fibers a) increases b) decreases
a
Age changes to ciliary body: connective tissue a) increases b) decreases
a
Age changes to ciliary body: extracellular material a) increases b) decreases
capillary plexus
Blood supply: what is present in each ciliary process that supplies blood?
Fenestrated Capillaries
Capillaries in the Ciliary Processes are Leaky, what type of capillaries are these?
a
Changes with Age: a) Ciliary body of a young eye b) Ciliary body of an older eye
b
Changes with Age: a) Ciliary body of a young eye b) Ciliary body of an older eye
cuboidal cells
Ciliary Epithelium is made of Double layered what cells?
b
Ciliary Muscle contracts to give a) outward movement b) inward movement
a
Ciliary Muscle is a ring of a) smooth muscle b) skeletal muscle
Supraciliaris (superciliary lamina)
Ciliary body attachment sites: Outermost layer of ciliary body (adjacent to sclera)
Scleral spur
Ciliary body attachment sites: region of circularly oriented collagen bundles that extends from inner aspect of sclera
Vitreous base
Ciliary body attachment sites: strong region of adhesion to basement membrane of Pars Plana epithelium, and inner limiting membrane of the retina BUT common spot for Peripheral retinal detachments
outer longitudinal portion /outer meridional portion (Brücke's muscle)
Ciliary muscle: what portion is A?
radial portion, middle oblique portion
Ciliary muscle: what portion is B?
inner circular portion
Ciliary muscle: what portion is C?
a
Ciliary processes are present at? a) pars plicata b) pars plana
b
Ciliary/scalloped bays are located at? a) pars plicata b) pars plana
b
Comprises giant dentate processes which are only present in 16% of eyes. a) pars plicata b) pars plana
a
Insertion of ciliary muscle tendons: - Type 1 from outer longitudinal muscle into sclera or scleral spur - Type 2, elastic-like to trabecular meshwork - Type 3 collagenous to trabecular meshwork and corneal stroma a) anterior insertion b) posterior insertion
a
Insertion of ciliary muscle tendons: - Type 2, elastic-like to trabecular meshwork a) anterior insertion b) posterior insertion
a
Insertion of ciliary muscle tendons: - Type 3 collagenous to trabecular meshwork and corneal stroma a) anterior insertion b) posterior insertion
supreciliaris, ciliary epithelium, ciliary stroma, ciliary muscle
List the main structural components o the ciliary body.
fibroblasts
Muscle bundles of the ciliary muscles are surrounded by flattened what? Instead of collagen fibres.
short posterior ciliary nerve
Name the nerve of the parasympathetic pathway that enters the ciliary muscle.
anterior chamber angle
What structure is C?
b
Pars Plana (orbicularis ciliaris) is a) highly vascular b) relatively avascular
a
Pars Plicata (corona ciliaris) is a) highly vascular b) relatively avascular
b
Pars plana a) Very vascular b) relatively avascular
orbucularis ciliaris
Pars plana is also called/known as?
a
Pars plicata a) Very vascular b) relatively avascular
corona ciliaris
Pars plicata is also called/known as?
Pars plicata (corona ciliaris)
Pleated/ridged surface, 70-80 folds - ciliary processes • ~2mm anterior/posterior length • Ciliary processes (largest are ~2 mm long, 0.5 mm wide, 1.0 mm high) • Minor processes (in valleys) • Giant processes (nasal) • Valleys (between processes) • Very vascular • Site of aqueous production • Includes ciliary muscle
b
Relatively avascular a) pars plicata b) pars plana
secretory granules
The Inner non-pigmented epithelium of the ciliary body contain what?
Vortex veins
The Venous drainage of the ciliary body is through the choroid via?
c
The ciliary stroma has a) myelinated nerves b) non-myelinated nerves c) both
a
The ciliary stroma... a) has blood vessels, highly vascular b) has no blood vessels, avascular
neural retina
The inner non-pigmented epithelium is continuous with what?
2/3rds
The pars plana is what fraction of the ciliary body?
70-80
The pars plicata is a pleated/ridged surface that makes up the ciliary processes and is composed of how many folds?
b
The pigmented epithelium of the ciliary body is in the... a) inner layer (towards the centre of the eye) b) outer layer (towards the surface of the eye)
trigeminal nerve
The sensory innervation of the ciliary muscle originates at what nerve?
a
The site of aqueous production is? a) pars plicata b) pars plana
superior cervical ganglion, carotid plexus
The sympathetic innervation of the ciliary muscle originates where?
Supraciliaris
Thin, outermost layer of loose connective tissue of ciliary body.
c
Trigeminal nerve, Nasociliary branch of ophthalmic division, long ciliary nerves a) sympathetic b) parasympathetic c) sensory
outer longitudinal, middle oblique, inner circular
What are the 3 types of ciliary muscle?
Melanocytes, fibroblasts, collagen
What cells are the supraciliaris composed of?
melanocytes, fibroblasts, mast cells
What cells is the ciliary stroma composted of?
ciliary muscle
What forms the bulk of the ciliary body?
contraction of ciliary muscle
What increases the size of the pore in the trabecular meshwork, opening the trabecular meshwork and facilitates drainage of the aqueous humour?
Pars plicata (anterior)
What is A?
Pars plana (posterior)
What is B?
Supraciliaris
What is adjacent to the sclera and allows the movement of the ciliary body?
basement membrane
What is continuous around ciliary muscle fibres?
1.0mm
What is the approximate height of the largest ciliary processes? in mm
2mm
What is the approximate length of the largest ciliary processes? in mm
4-4.5mm
What is the approximate length of the pars plana? in mm
2mm
What is the approximate length of the pars plicata? in mm
0.5mm
What is the approximate width of the largest ciliary processes? in mm
valleys of the pars plicata
What is the arrow pointing to in the pars plicata?
valleys of the pars plicata
What is the arrow pointing to?
loose connective tissue
What is the ciliary stroma made up of?
Edinger-Westphal nucleus (in brain stem), oculomotor nerve, ciliary ganglion, short posterior ciliary nerves
What is the parasympathetic nerve innervation pathway of the ciliary muscle? please write in order.
Trigeminal nerve, ophthalmic division, Nasociliary branch, long ciliary nerves
What is the sensory nerve innervation pathway of the ciliary muscle? please write in order.
loose connective tissue
What is the supraciliaris made of?
superior cervical ganglion, carotid plexus, long ciliary nerves
What is the sympathetic nerve innervation pathway of the ciliary muscle? please write in order.
b
What makes up 2/3rds of the ciliary body? a) pars plicata b) pars plana
Long posterior ciliary artery
What structure is A?
Punctum adherens
What structure is A?
basement membrane
What structure is A?
ciliary body
What structure is A?
ciliary muscle
What structure is A?
ciliary processes
What structure is A?
circular fibres of ciliary muscle
What structure is A?
maxillary capillary
What structure is A?
nonpigmented epithelium
What structure is A?
pigmented epithelium
What structure is A?
rectus muscle
What structure is A?
Major arterial circle of iris
What structure is A? Primarily supplies ciliary processes
Episcleral vessels
What structure is B?
Scleral spur
What structure is B?
Stroma
What structure is B?
anterior ciliary artery
What structure is B?
canal of schlemm
What structure is B?
fibres of suspensory liagements
What structure is B?
gap junction
What structure is B?
iris
What structure is B?
middle oblique fibres of ciliary muscle/ radial fibres of ciliary muscle
What structure is B?
nonpigmented epithelium
What structure is B?
pigmented epithelium
What structure is B?
Intramuscular circle
What structure is B? Supplies the posterior and outer ciliary body
Anterior ciliary arteries
What structure is C?
Collector channels
What structure is C?
Outer longitudinal fibres/ meridional fibres/ Brücke's muscle
What structure is C?
Supraciliaris (superciliary lamina)
What structure is C?
anterior chamber
What structure is C?
uveal tract
iris, ciliary body, choroid
a
superior cervical ganglion, carotid plexus, long ciliary nerves. This is the neural pathway of what innervation? a) sympathetic b) parasympathetic c) sensory
Infoldings of basal non-pigmented epithelium
what is this? provides the ciliary body with an enormous surface area available for fluid secretion
Pars Plana (orbicularis ciliaris)
what structure makes up 2/3rds of the ciliary body?
Pars Plana (orbicularis ciliaris)
• 4-4.5mm anterior posterior length (2/3rd of ciliary body) • Smooth flat surface • Scalloped posterior margin • Relatively avascular • Origin of zonules • Ciliary bays • Dentate processes/ retinal teeth • Giant dentate processes (16% of eyes)
Ciliary Epithelium
• Double layered, cuboidal cells • Outer pigmented (PE) - Extension of RPE - Melanosomes - Infoldings of BM •Inner non-pigmented (NPE) - Secretory organelles - Continuous with neural retina - Infoldings • Base out, apices in • Junctions
Ciliary Muscle Tendons
• Insert into surrounding structures • Posterior insertion: - Elastic attachment to anterior choroid & Bruch's membrane • Anterior insertions: - Type 1 from outer longitudinal muscle into sclera or scleral spur - Type 2, elastic-like to trabecular meshwork - Type 3 collagenous to trabecular meshwork and corneal stroma - Assists aqueous drainage
Ciliary stroma
• Loose connective tissue • Collagen/elastic network • Cells: melanocytes, fibroblasts, mast cells • Myelinated and non-myelinated nerves • Blood vessels, highly vascular
Supraciliaris (superciliary lamina)
• Thin, outermost layer of loose connective tissue • Adjacent to sclera, allows movement of Ciliary body • Melanocytes, fibroblasts and collagen
Ciliary Muscle
•Ring of smooth muscle •Located against inner surface of anterior sclera •Forms bulk of ciliary body •Fast action, multi-unit 3 parts: -Outer longitudinal/meridional (Brücke's muscle) -Middle oblique/radial -Inner circular (termed Muller's muscle) contract to give complete 3D inward movement
