Ocular Surgery Flashcards
what muscle closes eyelids and what is it innervated by?
obicularis oculi muscle
auriculopalpebral branch of fascial n.
uses for transpalpebral US (3)
- lens
- retrobulbar masses
- ocular chamber
tyndall effect looks at..
anterior chamber clarity
+ = uveitis
what part of LA eye exam is unique to LAs?
- digital palpation of palpebral fissure
- digital palpation of dorsal and ventral fornix of conjunctival sac
what disinfectant is safe on eyes?
diluted povidone iodine NOT chlorhexidine
block used for ocular akinesia in horses
-auriculopalpebral block
block used for ocular anesthesia in horses
-supraorbital n. block (branch of frontal n, which is branch of trigeminal)
block used for ocular akinesia in bovine
auriculopalpebral block (branch of fascial; targets obicularis oculi)
block used for ocular anesthesia in bovine
line block (often too hard to palpate in order to do supraorbital)
blocks used for BOTH ocular anesthesia and akinesia
retrobulbar blocks
- peterson block
- 4 point block
evaluating retrobulbar blocks (peterson, 4 point)
4
- proptosis (protrusion of eyeball)
- lack of eye movement when head is turned
- ipsilateral pupil dilation
- lack of corneal sensation
options for covering the cornea (3)
- third eyelid flap (mostly ruminants)
- temporary tarsorrhaphy
- reversible split lid tarsorrhaphy (RSLT)
surgical treatment for dermoids
lamellar superficial keratectomy
main causes of corneal ulcers in equine
- EHV-2
- pseudomonas
never use _____ on corneal ulcers
steroids
surgical treatment for corneal ulcers
conjunctival flap/graft
ideal suture placement for conjunctival flap/graft
80% thickness of cornea!!!
ideal sutures to place when doing a conjunctival flap/graft
simple interrupted using a semicircular needle inserted at 90 degrees using circular motion
equipment needed for conjunctival flap/graft
- bishop-harmon forceps
- stevens tenotomy scissors
- castroviejo needle drivers
surgical treatment for entropion
short term:
- skin mattress sutures
- skin staples
- Michael wound clips
permanent:
-Hotz Celsus
hotz celsus is used to treat
entropion (usually only severe cases like cicatricial entropion)
causes of entropion in LAs (5)
- congenital
- dehydration in newborns
- microphthalmus (BVD)
- spastic (secondary to pain)
- cicatricial entropion (secondary to scarring)
cicatricial entropion
secondary to scarring
enucleation
removal of glove ONLY
removal of globe ONLY
enucleation
eviseration
removal of intraocular contents ONLY
removal of intraocular contents only
eviseration
when is eviseration commonly used?
for cosmetic reasons in horses
involves removing intraocular contents ONLY
exenteration
removal of globe AND oribital soft tissues
mainly used in cattle
main complications of exenteration
hemorrhage
entering maxillary sinus-> no longer sterile
orbital fractures are considered open if…
they enter maxillary sinus
gonioimplant
used to treat glaucoma. increases drainage of aqueous fluid
treatment for chronic glaucoma (2)
evisceration (intraocular contents only) or enucleation (globe only)
surgical treatment for cataracts
phacoemulsification
phacoemulsification
used to treat cataracts
ERU often leads to _____ synechia
posterior (lens sticks to iris
anterior vs. posterior synechia
anterior: lens sticks to cornea
posterior: lens sticks to iris
surgical treatment options for ERU
- intravitreal injections
- suprachoroidal cyclosporine implants
- pars plana vitrectomy (PPV): risk for retinal detachment!!
pars plana virtectomy
surgical treatment for ERU
risk for retinal detachment!
suprachorodial cyclosporine implants
treatment option for ERU
how to collect samples for testing in ERU cases (rarely done)
paracentesis
