Ophthalmic Surgery Flashcards
Which solutions cannot be used on the eye?
alcohol and detergents
Which solution can be used to prep the eye for surgery?
1:50 (2%) iodine/saline solution
How many layers are closed in eyelid laceration repair?
2 layers
- deep and skin
How is the deep layer closed in eyelid laceration repair?
- bites perpendicular to eyelid
- simple continuous
How is the skin closed in eyelid laceration repair?
- start 4mm from eyelid margin, exit 1 mm from margin
- figure of 8 suture pattern
- 5/0 or 6/0 Vicryl
How much of the eyelid margin must a mass take up to be surgically removed?
over 1/3
What is the most common tumor or the eyelid in dogs?
Meibomian gland adenoma
What percentage of canine eyelid tumors are benign?
73%
How is an eyelid tumor removed?
H-shaped resection
What procedures can be done for eyelid resection, after a tumor has been removed?
- single pedicle advancement flap
- lip to lid flap
- single pedicle advancement flap with conjunctival graft
- semi-circular flap
When should the lip to lid flap technique be used for eyelid resection?
for defects of the lower lid
When should the single pedicle advancement flap with conjunctival graft technique be used for eyelid resection?
for full-thickness defects
When should the semi-circular flap technique be used for eyelid resection?
defect in the lateral commisure or upper lid area
What is the most common eyelid tumor of the cat?
squamous cell carcinoma
What is eyelid angenesis?
- failure of eyelid to form
- skin attached directly to the globe
What is entropion?
inward turning of the eyelid
What are the clinical signs of entropion?
- ocular discomfort and self trauma
- epiphora
corneal erosion, ulceration, and visual defects
Describe the congenital form of entropion
- usually bilateral
- lower lateral lid more common
- patients < 6 months
What is the cause of the acquired form of entropion?
associated with lid spasm due to:
- corneal ulcers
- KCS
- foreign body
What are the surgical options to treat entropion?
- eyelid tacking
- Hotz celsus
- Modified Hotz celsus
- Arrowhead resection
Describe the Hotz Celsus Hemostat technique
- cutting out a piece of skin to cause eversion of eyelid
- grasp skin with hemostat and leave on for 30 seconds
Describe the Hotz Celsus Incision method
- make crescent shaped incision 2 mm from margin
- cut out the amount of tissue based on entropion severity
- suture incision line
When should the Modified Hotz Celsus procedure be used?
medial canthal entropion
When should the arrowhead resection be used?
upper and lower lateral canthal entropion
What is ectropion?
eversion of the eyelid
How is ectropion treated?
- no treatment needed unless clinical signs present
- wedge resection
- V-Y blepharoplasty
What are common diseases of the nasolacrimal system?
- puntal aplasia
- micropunctum
- trauma and scarring
- KCS
What are the clinical signs of nasolacrimal disease?
- epiphora
- periorbital alopecia and tear staining
- conjunctivitis
Which tests are used to diagnose nasolacrimal diseases?
- Jones 1 test (eye stain)
- Nasolacrimal flushing
- Dacrypcystorhinography (dye)
How is punctal aplasia treated?
- inject saline into normal puncta
- located bubble forming in occluded puncta
- nip off the occluded membrane
How is micropunctum treated?
- with tips or iris scissors, widen the orifice of the puncta
How is nasolacrimal trauma diagnosed and treated?
- inject air into puncta and look for bubbles
- cannulate both side of laceration and leave for 3 weeks
What are the functions of the nictitating membrane?
- tear production
- protect globe
- remove debris from cornea
What is everting nictitating membrane and how is it treated?
- eversion of cartilage
- surgical excision
What is prolapsed nictitating membrane?
- gland flips up dorsally above leading edge
- most common disorder of 3rd eyelid
What are the surgical options for cherry eye?
- excision of membrane (not recommended)
- orbital rim anchoring technique
- Morgan pocket technique
Describe the orbital rim anchoring technique
- small incision in anterior conjunctiva
- pass 4/0 suture through hole and engage periosteum
- continue purse string around the gland and tie
What is the most common neoplasia of the nictitating membrane?
squamous cell carcinoma
Describe the subconjunctival approach of enucleation
- lateral canthotomy first
- excise 5mm eyelid margins and 3rd eyelid
- transect extraocular muscles at level of globe
- retract eye out of orbit
- ligate and sever optic nerve
Describe the subconjunctival approach of enucleation
- suture eyelids together
- incision 5mm around palpebral fissure
- transect extraocular muscle along orbital rim
- remove all ocular tissue
What is traumatic proptosis?
sudden blow to orbit which increases IOP
- eyelid entraps posterior to globe
When should a proptosis be enucleated?
- if 2 or more rectus muscles are avulsed
- if the globe is ruptured
How is proptosis treated?
manual reduction using eyelid sutures or lateral canthotomy
- then temporary tarsorrhaphy
