Eyelid and Third Eyelid Flashcards
Canine eyelid neoplasia basics
Usually benign
Irritation, corneal ulcers
Surgical excision, cryotherapy
Histopath!
Types of canine eyelid neoplasia
Meibomian adenoma Epithelioma Melanomas Papillomas Mast cell tumor
Feline eyelid neoplasia basics
Tend to be malignant
Radical excision, chemo, radiation
Tyoes of feline eyelid neoplasia
SCC: aggressive locally, ulcerative, will occasionally metastasize, associated with actinic radiation, most prevalent in older white cats
Mast cell tumor
Basal cell carcinoma
Fibrosarcomas
Surgical techniques
If less than 1/3 to 1/4 of lid involved, use V or four-sided excision
For larger defects: sliding skin grafts (H plasty), Rotation skin graft, Landolt; Mustarde, sliding z plasty, lip-to-lid
Two layer closure for all but the smallest defects
Third eyelid basics
Nictitating membrane
Semilunar fold of conjunctiva in front of globe ventromedially
Support structure is T shaped cartilage
Gland at its base
Cherry eye
Young dogs, cockers, bulldogs, other brachycephalics; uncommon in cats (but they occur!) Pathogenesis - CT weakness - Inflammation - Hypertrophy Sequelae - Local irritation - Chronic inflammation, conjunctivitis - Ocular discharge Diminished tear production - dry eye
T/F: the meibomian glands produce most of the tears for the eye
False; lacrimal
How to fix cherry eye
DO NOT REMOVE THE GLAND
Only medical treatment, 43% develop KCS
Gland replacement (and preservation), 14% develop KCS
Hence, sx is indicated, but potential for KCS (dry eye) persists
Cherry eye tx
Conjunctival mucosal techniques - Envelope (Moore) - Pocket (Morgan)** most common Intranictitans tacking - To TE cartilage Anterior nictitans anchoring - To ventral orbital rim Posterior nictitans anchoring - To ventral periorbital fascia - To ventral equatorial sclera - To ventral oblique muscle - To ventral rectus muscle
Pocket procedure
Two semi-circular incisions of the mucosa at the base of the enlarged and prolapsed gland Ends of incision do not touch Undermine conjunctiva to pull over gland Appose with continuous suture Tie knots on the anterior face of TE Nictitans mobile after Sx
Bent cartilage
Eversion of shaft of TE cartilage Large and giant breeds - GD - Saint Bernard - Mastiff - German Short-haired Pointer Pathogenesis - More rapid growth of the posterior (inner) portion of the cartilage compared with the anterior (outer) portion Sequelae - Chronic conjunctivitis Ocular discharge
T/F: Third eyelid neoplasia is more common in dogs than cats and horses/cows
False; more common in cats and horses/cows
- Adenomas/adenocarcinomas
- Papillomas
- Hemangiomas/hemangiosarcoma
- Lymphosarcoma
- Melanoma
- SCC