Vitreous Humor Flashcards
what is the volume of the vitreous humor
4mL (80% of the eye)
what are the main functions of the vitreous humor
stores metabolites for the retina and lens, shock absorber and transmits and refracts light
what is the impression in the anterior vitreous called
the patellar fossa
what do all the surfaces have that interface with the vitreous
a basement membrane
what are the 3 zones of the vitreous
cortex, intermediate zone, and cloquet’s canal
what zone of the vitreous is the most dense
cortex
what zone is the most outer area
the cortex
what is another name for the cortex
hyaloid surface
how thick is the cortex
100mm thick
what is the vitreous base
the most extensive adhesion (in the ora serrata)
which direction are the collagen fibers embedded in the vitreous base
perpendicular to the basement membrane of the NPE of the ciliary body
where is the anterior cortex
anterior to the vitreous base and adjacent to the ciliary body, posterior chamber, and lens
what is the attachment called between the posterior lens capsule and the anterior face of the vitreous
the ligamentum hyaloideacapsulare (retrolental ligament)
does the retolental ligament weaken with age
yes, it is firm when young
what is the space of Berger
a potential space within the center of the retolental ligament (between the lens and vitreous)
where is the posterior cortex
posterior to the vitreous base and in contact with the retina
what is the vitreoretinal interface
the outermost portion of the posterior cortex that contains anchoring fibrils that merge with the internal limiting membrane of the retina
What is present after a PVD (posterior vitreal detachment)
a white ring presents around the optic disc called a Weiss Ring
why does the retina hemorrhage when there is a vitreal traction
there are fine strands from the vitreous cortex and pass through the internal limiting membrane to surround the blood vessels
what is inside the intermediate zone
fibers running anterior-posterior from vitreous base to the posterior cortex
what is the channel called that runs through the center of the vitreous body
Cloquet’s canal or Hyaloid channel
what is the space or tent of Martegiani
the funnel-shaped area over the optic nerve where cloquet’s canal attaches posteriorly
what shape does the cloquet canal follow
an S shape (not a straight line)
what type of vitreous are the zonules considered to be
tertiary vitreous (derived from NPE during embryological development)
how much water is the vitreous made up of
99%
why is the vitreous have viscoelastic properties
from the combination of hyaluronic acid and collagen
what maintains the spacing of the collagen fibers in the vitreous
hyaluronic acid
what happens to the vitreous as we age
it liquifies, more watery
where is the strongest attachment of the vitreous base
in the ora serrata
where is the vitreous attached in the eye
ora serrata, posterior lens, optic disc, macula and retinal vessels
