sclera and episclera B6 Flashcards
This forms the posterior 83% of the connective tissue of the globe.
Gives the eye its shape, rigidity, and resistance to external forces.
Offers a place to anchor the EOM’s
Sclera
Sclera is a thick, ________________ tissue layer that is continuous with corneal stroma at the limbus
dense connective (The scleral composition has fibrils that are arranged in irregular bundles that branch and interlace)
What is difference between cornea and scleral collagen?
Cornea collagen is a uniform diameter and bundled regular
Sclera is irregular and random (superficial bundles are narrower and thinner than the deeper bundles)
_________ fibers have a low incidence in the sclera between and sometimes within bundles
Elastic
_____________ are also present in the sclera, although they are less numerous than in the cornea.
Fibroblasts
True/False: Stromal ground substance is similar to corneal ground substance but contains fewer GAGs.
True
The trabecular meshwork and angle connect to what on the sclera?
Scleral spur (significant because in gonioscopy, you can look here to see if angles are open or closed)
Know everything about scleral spur…
Light band on gonioscopy
The opacity of the sclera depends on a number of factors, what are they?
Number of GAGs
Amount of water
Size and distribution of collagen fibrils
The sclera is relatively ___________, (68%) compared with the cornea.
dehydrated
Weakest link of the sclera is where?
where the optic nerve leaves the eye
The hole where the optic nerve passes is not really a hole or foramen, in its place is a meshwork of connective tissue called ______________.
Lamina Cribrosa
Sclera is considered _________ because it contains no capillary beds.
avascular
Sensory innervation is supplied to the posterior sclera by branches of the ____________.
short ciliary nerves
Myopia progression caused by axial elongation in a highly myopic eye causes ______________, at the posterior pole where the collagen fibril diameter and bundle size are smaller.
scleral thinning
