Card Set Information

2013-11-04 17:59:20
VPFC clinical

Ophthalmic lesions and examination techniques
Show Answers:

  1. What is the first diagnostic process to do when dealing with eye disease?
    Clinical examination of whole animal, don't jump straight to the obvious lesion
  2. Sequence of eye examination:
    • Perform in a dark room
    • Assess both eyes
    • Examine from a distance
    • Examine from outside to inside
    • Dazzle/menace response and PLR
    • Can animal see? Ask owner
    • Shirmer tear test and fluorescein
  3. Entropion
  4. Entropion
    • Breed predispositions: Rotties and Shar pei
    • Anatomical defect: need to evert lid to see margin
    • Surgical correction: Holz-Celcus
    • Puppies: don't ignore, eyelid tacking
    • Eyelid neoplasia
    • Mostly sebacious adenoma
    • Old dogs
    • Full thickness wedge resection - early
    • Can remove up to 1/3 length of lid
    • Need to avoid 'step' in lid margin
    • "Cherry eye": third eyelid gland prolapse
    • Very common in young dogs
    • Tx: surgical replacement of glands
    • Ddx: scrolling of cartilage of 3rd eyelid - common in giant breeds
    • Keratoconjuctivitis sicca (dry eye)
    • Lack of aqueous tear production leads to conjunctivitis & superficial keratitis
    • Very sore
    • Mucopurulent ocular discharge
    • Secondary corneal ulceration
    • Dx: STT <10mm per minute
    • Very common
    • Always perform STT with chronic/recurrent conjuctivitis
    • Keratoconjuctivitis sicca
    • This is clinical presentation when aqueous tear production is very low
    • Corneal ulceration: very common in all species
    • Dx: fluorescein and close examination
    • Tx: dependent on cause, can be surgical or medical
    • Always try to determine cause
    • Shallow ulcer should heal within a week esp in young dog
  5. Causes of corneal ulceration
    • Dystrophy (eg: boxer ulcer)
    • Trauma
    • KCS
    • Eyelid/eyelash abnormality
    • Foreign body
    • Exposure (prominent globe eg Peke)
    • Descemetocoele
    • Deep ulcer: ophthalmic emergency
    • Look at edge of ulcer to estimate depth
    • Tx: surgical repair - this is referral surgery, has very high success rate
    • Always give owner the option
    • Melting ulcer: liquefactive stromal necrosis
    • Complications: Pseudomonas infection - very rapid progression
    • Feline corneal sequestrum
    • Very common in cats
    • Equine fungal keratitis
    • Usually caused by using topical steroids on ulcerated cornea
    • Infectious bovine keratoconjuctivitis aka pinkeye
    • Moraxella bovis
    • UV, dust and flies increase risk
    • Tx: topical antibiotics
    • Perforation
    • Occasionally ulceration can lead to perforation
    • Protruding mass out of eye is usually iris prolapse
    • Uveitis
    • C/S: red eye; pupil constriction; cloudy eye; iris reddening
    • Recognise early and treat aggressively
    • Not that common
  6. Causes of uveitis
    • Traumatic (especially if unilateral)
    • Infectious: especially cats (FIV/FeLV/FIP/toxo)
    • Lens induced: cataract or lens luxation
    • Systemic: neoplasia or autoimmune
    • Mostly idiopathic
  7. Glaucoma
    • More common than uveitis
    • Raised intraocular pressure (measured by tonopen or schiotz tonometer) is diagnostic
    • Ophthalmic emergency
    • 72 hours to permanent blindness
  8. Clinical signs of glaucoma
    • Ocular pain
    • Blindness in affected eye
    • Episcleral congestion - red eye
    • Corneal oedema (steamy cornea)
    • Mydriasis (dilated pupil)
  9. Glaucoma
  10. Causes of glaucoma
    • Inherited or primary (goniodysgenesis): defect in drainage angle - treat both eyes
    • Secondary:
    • lens luxation
    • chronic uveitis
    • intraocular neoplasia
    • May occur simultaneously with uveitis
    • Lens luxation
    • Common in middle aged terriers
    • Often present with corneal oedema and secondary glaucoma
    • Tx: surgical lens extraction saves vision
  11. Lens luxation
  12. Cataract
    • Clouding of lens due to changing protein content
    • Ddx: Dogs >9yo have some degree of lens clouding but can see through it. Cataracts opaque
    • Common causes:
    • inherited
    • metabolic (diabetes mellitus)
    • Others: age, secondary to intraocular disease, traumatic
    • Tx: referral surgery only option
    • Sx: $3000 unilateral, $4-4500 both eyes
    • Retinal detatchment
    • Old cats - associated with hypertension
    • Looks like curtain in back of eye
  13. Inherited retinal disease
    • Most common in dogs: Progressive retinal atrophy (PRA)
    • PRA seen in middle aged breeds esp Labs & spaniels
    • Leads to gradual deterioration of vision
    • Other disease includes:
    • collie eye anomoly
    • retinal dysplasia
  14. Sudden onset blindness
    • Cats: most commonly is retinal detachment due to systemic hypertension
    • Dogs: most commonly is Sudden Acquired Retinal Degeneration (SARDs) - middle aged dogs
    • Rare in horses and production animals
    • Refer