Glaucoma Flashcards
Glaucoma (2)
1) multifactorial disease
2) elevation of IOP incompatible with ocular health
Glaucoma pathogenesis (3)
1) reduced aqueous humor drainage capacity in ALL cases
2) results in progressive IOP elevation
3) irreversible vision loss through optic nerve & retinal ganglion cell death
Primary Glaucoma (2)
1) heritable, breed-related abnormality of aqueous drainage angle
2) rarely congenital
Secondary Glaucoma (1)
numerous causes of secondary drainage angle obstruction
Glaucoma clinical signs in acute disease (5)
1) blepharospasm
2) corneal edema
3) episcleral injection
4) dilated pupil
5) variable vision
Glaucoma clinical signs in chronic disease (5)
1) all acute signs possible
2) buphthalmos- swelling of eye
3) Haab’s striae- fracture/break in decimates membrane, streaks across cornea
4) lens subluxation- crescent appearance to lens
5) cupped optic nerve
Causes of canine primary glaucoma (4)
1) breed-related/hereditary condition
2) drainage angle abnormality
3) bilateral disease potential
4) one eye affected first then second weeks to months later
Causes of canine secondary glaucoma (6)
1) lens luxation
2) uveitis
3) hyphema
4) intraocular neoplasia
5) Melanocytic glaucoma
6) pigmentary uveitis
7) pseudophakia/aphakia
8) trauma
Feline glaucoma (4)
1) primary glaucoma is rare
2) secondary similar causes as dogs
3) uveitis common cause of secondary
4) aqueous humors misdirection (unique to cats)
Equine glaucoma (2)
1) primary glaucoma is rare
2) most cases secondary to equine recurrent uveitis (ERU)
Clinical findings in equine glaucoma (6)
1) usually an insidious disease
2) corneal edema (intermittent or persistent)
3) dilated pupil
4) Haab’s striae
5) lens luxation
6) vision loss
Glaucoma diagnosis (4)
1) clinical signs/findings
2) history/signalment
3) IOP measurement
4) Gonioscopy
Tonometry (5)
1) measurement of IOP
2) methods: rebound, applanation, indentation
3) 15-25 normal
4) abnormal: IOP differences between 2 eyes
5) important for assessing efficacy of glaucoma therapy
Gonioscopy (3)
1) examination of the drainage angle
2) requires specialized lens
3) helps determine likelihood of primary glaucoma based upon angle morphology
Goals of therapy (3)
1) maintenance of vision where possible
2) patient comfort in all cases
3) prophylaxis in “at risk” eyes