The Red Eye Flashcards
where can you see redness
Eyelids Conjunctiva/episclera/sclera Third eyelid Cornea Anterior chamber Anterior uvea Posterior uvea/Retina Retrobulbar area
3 parts of an eyelid that can become red
skin, melbomian glands, conjunctiva
causes of eyelid redness
Hyperemia, swelling, ulcers, crusts, loss of hair
affect of eyelid damage
effects cornea and tear film
hyperaemia - irritates white of the eye
corneal irritation - vascularization
How do we get red conjunctiva/episclera /sclera
eyelids, third eyelid, sclera
Ends at the limbus
properties of conjuntival blood vessels (bv)
dichotomous branching
v.sensitive to surface irritation
causes of dilation + separation of endothelial cells of conjuntival bvs
hyperaemia
oedema (chemosis)
properties of episcleral bvs
no dichotomous branching
larger
meandering
causes of problems in episcleral bvs
intraocular disease (uveitis + glaucoma) severe/chronic surface irritation
makeup of the sclera
the “white of the eye”
fibrous tunic
collagen fibres + fibroblasts
emisaria (holes for bvs + nerves)
4 layers of the cornea (from external to internal)
Epithelium
Stroma
Descemet’s membrane
Endothelium
properties of the epithelium of the cornea
hydrophobic
doesn’t have blood vessels
has nerves
properties of the stroma of the cornea
hydrophilic
stays relatively dehydrated
how does the stroma keep in optimal conditions
endothelium pumps fluid into the AC
epithelium provides a passive barrier
what do we call stromal overhydration
corneal oedma
what can cause corneal oedema
ulceration
glaucoma
uveitis
vascularisation
what does the aqueous humour (AH) do
establishes IOP
It feeds the posterior cornea and the anterior lens
Comes from the ciliary body into the posterior chamber (PC)
Goes through pupil into AC + exits through the ICA/uvea/sclera
what two diseases affect the AC
uveitis
glaucoma
what is the anterior uvea made up of
iris
capillary body
muscles + blood ocular barrier
what is the posterior uvea
choroid
tapetum lucidum
common denominator of the uvea
mesh of blood vessels
usually has a lot of pigment
endothelial cell separation into the AC can be in how many forms
keratic precipitates, hypopion, hyphema, fibrin
what is adhesion of the iris to the anterior lens
Posterior synechiae
effects of preiridal fibrovascular membranes (PIFMs)
rubeosis iridis - grow over iris, pale iris seen
hyphema - bleeding in the eye
a type of secondary glaucoma - blockage of ICA
causes of sudden decompression of the anterior uvea
Infl
Anterior synechiae
Bleeding from the iris and ICA
causes of a red anterior uvea
corneal perforation
iris + lens damage (bleeding, cataract)
foreign body
causes of a red posterior uvea
posterior + anterior uveitis
bleeding in the anterior segment of the eye
retinal detatchment
causes of a red retrobulbar area
infl + infection
neoplasia
causes of infl + infection in the retrobulbar area
- Stick injuries through mouth
- Originating from a middle ear abscess
- Conjunctival foreign bodies that travel posteriorly
- Through general circulation
- Blunt trauma – bleeding/hemorrhage
- Parasitic diseases
retrobulbar area problems can lead to
altered position of the eye in the orbit
altered relationship with the eyelid
possible incr pressure around the eye
swelling/infection of tissues around it
the 3 ancillary tests
STT-1
Fluorescein
Tonometry
