The Blind Eye Flashcards
What are some common causes of blindness?
Symblepharon Keratitis Persistent pupillary membranes Uveal problems Cataracts Glaucoma Fundic disease
What is symblepharon?
Two layers stuck together:
Conjunctiva and cornea
Eyelid and cornea
Eyelid and conjunctiva
What is a key cause of symblepharon in kittens/cats ?
What is the general pathogenesis?
FHV type I
Causes ulceration of the conjunctiva and cornea
- wounds stick together and create adhesions
(Uncommon)
What type of keratitis is common in brachys?
Pigmentary keratopathy
- pigment on cornea
- occurs secondary to entropion, distichiasism, eurynlepharon
What is euryblepharon?
Large palpebral fissure
What is lagopthalmus?
inability to close eyelid completely
How do you treat patients with pigmentary keratopathy due to brachycephalic ocular syndrome?
Surgical correction of euryblepharon (etc)
What is the pupillary membrane
Embryologic membrane that should regress
Originates from iris colarette
BVs which emerge from middle part of iris and nourish lens during development
What can PPMs cause?
Corneal and/or lens opacity
What clinical signs are associated with uveitis?
FLARE - Tyndall effect
Hypopion +/ hyphaema
Synechia - adhesions between iris and cornea or lens
DECREASED IOP - can increase if chronic
Why do you see reduced IOP in patients with acute uveitis?
Ciliary body doesn’t produce as much aqueous humour
What is the uvea?
All the vascular tissue in the eye
- iris and ciliary body - anterior
- choroid - posterior
What causes flare?
Increased proteins in the anterior chamber
Does hypopion always indicate infection?
NO
Usually STERILE
What is the difference between anterior and posterior synechia?
Anterior - iris adheres to cornea
Posterior - iris adheres to lens
How can you differentiate between PPMs and synechia ?
PPM - originates from iris colarette (middle segment)
Synechia - comes from margin of iris
What complications can occur due to uveitis?
Why?
Corneal oedema - damage to endothelium which usually pumps out fluid
Cataracts - poor nourishment to lens
Synechia
Retinal detachment - inflammation of choroid
Lens luxation in cats
Glaucoma - accumulation of inflammatory cells etc
What causes uveal problems ?
- systemic hypertension
- infectious
- immune mediated
- neoplastic
- complicated ulcers