2. Limbus
• Anatomical Limbus
Anterior limit of limbus formed by a line joining end of
Bowman’s and end of Descemet’s (Schwalbe’s Line)
Posterior limit is a curved line marking transition between
regularly arranged corneal collagen fibers to haphazardly
arranged scleral collagen fibers
Type to enter a caption.
3. Limbus
• Surgical Limbus
1.5 to 2mm wide corneoscleral junction
2 Equal zones
1. Anterior bluish gray zone (Between Bowman’s and Schwalbe’s line)
2. Posterior white zone ( Between Schwalbe’s line. And scleral spur)
4. Limbus
• 5 structures
1. Conjunctiva and limbal palisades
2. Tenon capsule
3. Episclera
4. Corneoscleral stroma
5. Aqueous outflow apparatus
Type to enter a caption.
5. Limbus
At Limbus,
• Corneal epithelium becomes bulbar conjunctiva
• Bowman’s membrane becomes continuous with the lamina
propria of conjunctiva and tenon capsule
• Stroma becomes sclera.
• Descemet membrane becomes schwalbe’s line.
• Endothelium lines TM
6. Anterior Chamber
• Angular space.
• Bordered anteriorly by the cornea. And posteriorly by the
iris diaphragm and pupil.
• 3mm deep at its center
• Deeper in aphakia, pseudophakia and myopia
• Shallower in hyperopia, children and older people.
• AC depth decreases by. 0.01 mm/ year of life.
7. Anterior Chamber
• Chamber Depth is slightly diminished during
accommodation, partly by increased lens curvature and
partly by forward translocation of lens.
• Chamber deepens by 0.06mm for each diopter of Myopia.
8. Angle of Anterior Chamber
1. Schwalbe’s line
2. Trabecular meshwork
3. Scleral spur
4. Anterior surface of colliery body along with root of iris
9. Schwalbe’s Line
• This marks the anterior border of angle and represents
termination of descemet’s membrane.
• Seen as glistening white line gonioscopy.
10. Schwalbe’s Line
• Prominence of Schwalbe’s line is known as posterior
embryotoxon seen in Axenfield Reiger’s anomaly.
11. Schwalbe’s Line
• Pigments along Schwalbe’s line are known as
Sampaolesi’s line, seen in pigmentary glaucoma and PXF
syndrome.
12. Schwalbe’s Line
Schwalbe’s line marks transition from
• Trabecular to corna endothelium
• Termination of the Descemt’s membrane.
• Insertion of TM to cornea stroma.
13. Trabecular Meshwork
• A sievelike structure made up of connective tissue lined by
trabeculocytes, which have contractile and phagocytic properties.
• It’s main function is drainage of aqueous humour.
• The TM is triangular in cross section
• Apex is at Schwalbe’s line
• Base is by scleral spur and CB.
15. 1.Uveal Meshwork
• Innermost , cord-like endothelial cell-
covered strands arising from the iris
and CB storm.
• 25-75 micrometer
• Intertrabecular spaces are relatively
large and offer little resistance to the
passage of aqueous.
16. 2.Corneoscleral meshwork
• External to uveal meshwork
• Thickest portion of the trabeculum composed of layers of
connective tissue strands with overlying endothelial-like cells.
• 5-50 micrometer
• Intertrabecular spaces are smaller than uveal meshwork.
• Greater resistance to flow
17. 3.Juxtacanalicular
(cribriform)meshwork
• Outer part of trabeculum and links to corneoscleral meshwork
with the endothelium of the inner wall of the Schlemm canal.
• Consists of cells embedded in a dense extracellular matrix.
• Narrow intercellular spaces (10 micrometers)
• Normal resistance to aqueous outflow.
18. Schlemm canal
• Circumferential channel within the perilimbal sclera
• Inner wall is lined by irregular spindle-shaped endothelial cells containing
giant vacuoles (to convey aqueous via formation of transcellular pores).
• Outer wall is lined by smooth flat cells and contains the opening of
collector channels which leave the canal at oblique angles and connect
directly or indirectly with episcleral veins.
19. Schlamm canal
• Most aqueous vessels
are directed posteriorly
with most of these
draining into episcleral
veins
• A few across the
subconjunctival tissue
and drain into
conjunctival veins
20. Schlamm canal
• Episcleral veins drain into the cavernous sinus via anterior ciliary and
superior ophthalmic veins.
• Conjunctival veins drain into superior ophthalmic or facial veins via the
palpebral and angular veins.
21. Scleral Spur
• Wedge shaped circular ridge
• Pale, translucent narrow strip of
scleral tissue
• Composed of a group of fibers
know as Scleral Roll.
• Scleral Roll is composed of 75-
85% collagen and elastic tissue.
23. Scleral spur
• Contraction of longitudinal ciliary muscle opens up trabecular spaces.
• Scleral spur prevents ciliary muscle from causing Schlemm’s canal to collapse.
• Individual scleral spur cells are innervated by unmyelinated axons.
24. Ciliary Band
• Marks the posterior most part of the angle.
• Represents the anterior face of CB between its attachment to the scleral
spur and insertion of iris.
• Width depends on the level of iris insertion
• Wide in Myopes.
• Narrow in Hypermetropes.
• CB appears as a grey dark brown band.
• Consists of longitudinal fibers.
• Contraction of longitudinal open the TM and schlemm’s canal.
25. Ciliary Band
Innervation
• Derives from the supraciliary nerve plexus and the ciliary plexus in the
region of scleral spur.
• Both sympathetic adrenergic and parasympathetic and sensory
innervation- present.
