Orbit and Adnexa Dx in Small Animals Flashcards
Eyelash Anatomy
1. Distichia
2. Ectopic Cilia
3. Trichiasis
- Double line of lashes from grey line and gland = Staffy, bulldog
- Comes out from conjunctiva on upper lid = Retrievers, staffy
- Normal fur in eye
Eyelash and Eyelid Disorders - Progression
Distichiasis = continuous low level irritation
Entropion = continuous moderate-severe irritation
Ectopic cilia = intermittent moderate-severe irritation (4-6wk w cilia regrowth cycle)
Distichiasis
1. Definition
2. Clinical Significance
3. Clinical Signs
4. Tx
- > /1 hairs from free lid margin
- Variable
- Lacrimation, blepharospasm, epiphora
- Epilation (forceps), diathermy/ electrocautery, surgical resection, cryo
Ectopic Cilia
1. Definition
2. Clinical Significance
3. Clinical Signs
4. Tx
- Hair from palpebral conjunctiva
- Yes
- Acute, intense blepharospasm, corneal ulcer
- Surgical resection
Trichiasis (inc nasal fold)
1. Definition
2. Clinical Significance
3. Clinical Signs
4. Tx
- Normally located but abnormally directed hairs
- Variable
- Chronic corneal irritation, lacrimation, blepharospasm
- Surgical correction
Entropion
Inversion of all or part of the margin of the eyelid
Congenital
4-7mths
2° from pain
Clinical Signs
* Lacrimation
* Blepharospasm
* Poor corneal health
Entropion - Conservative Tx
Growing puppies until 12-18mths
Shar peis = 12wks
Ocular lube
Tacking sutures
Monitor
Entropion - Surgical Management
Holtz-celsus
+/- Medial canthoplasty
+/- lateral palpebral ligament resection
Eyelid Masses
Dogs = common
* Sebaceous adenoma
* Squamous papilloma
* Melanoma
Cats = SCC
Quantitative Tear Deficiency = KCS Causes
- Immune mediated**
- Neurogenic (innervation issue – unilateral with dry nostril as well!)
- Congenital hypoplasia (miniature breeds)
- Iatrogenic
- Iatrogenic removal of nictitans gland
KCS Diagnosis
» Inflammation (conjunctival hyperaemia)
» Mucoid – mucopurulent discharge, adhering to cornea
» Dull cornea
» Severe = corneal vascularisation and pigmentation
» Schirmer Tear Test (STT1) and clinical signs <10mm/min
KCS Medical Management
Cyclosporine A 0.2% (Optimmune)
* Immunomodulation inhibiting T-
cells
* Stimulates tear production
* BID
Tacrolimus (Protopic)
* Calcineurin inhibitor
* Second line treatment
Pilocarpine
* Neurogenic KCS only (unilateral
dry eye and nostril)
* 1 drop of 2% topical pilocarpine
per 10kg BW given BID ORALLY
Prolapse of the NM gland (Cherry Eye)
Bulldog, Lhasa Apso, Mastiff
Uni/bilateral
<2yrs = hypertrophic
Uncorrected = chronic conjunctivitis, ocular discharge
Surgical repositioning = new pocket
Congenital and Acquired NL Dx
Epiphora - normal tear production, abnormal drainage
STT
Fluorescein to nares = Jones test
Nasolacrimal flushing
Congenital
- micropuncta and canaliculi
misplacement = brachy and toy
Medial canthal entropion
Acquired
- Dacryocystitis
- FB
Nasolacrimal Dx Tx
Normograde irrigation
Topical/ GA
Common Causes of Orbital Dx
Inflam +/ FB
- Cellulitis
- Abscess
- Myositis
Neoplasia
- Orbital
- Metastatic
- Locally invasive
Trauma
Salivary lesions = cyst
Orbital Dx - Signalment
Infection = younger dogs
Neoplasia = older
Brachy = proptosis
Orbital Dx - Diagnosis
» Exophthalmos
» Strabismus and pupil position
» Retropulsion
» Pain on opening the jaw
» Facial swelling and symmetry
» Nictitating membrane protrusion
Exopthalmos
1. Definition
2. Cause
3. Frequency
4. 3rd eyelid position
5. Retropulsion
6. IOP
7. Oral exam
8. Dorsal view
9. Corneal diameter
- Normal globe pushed forward
- Cellulitis, abscess, neoplasia
- Uni
- Elevated
- Not possible
- Normal IOP
- Pathology
- Globe rostral to orbit
- Normal
Buphthalmos
1. Definition
2. Cause
3. Frequency
4. 3rd eyelid position
5. Retropulsion
6. IOP
7. Oral exam
8. Dorsal view
9. Corneal diameter
- Normally positioned, enlarged
- Increased IOP = glaucoma
- Uni = Bi
- Normal
- Possible
- Increased
- No pathology
- Globe normally positioned
- Increased
Orbital Cellulitis and Abscess Presentation
» Acute, unilateral exophthalmos
» Protrusion of nictitating membrane » Hyperaemia and chemosis
» Periocular swelling
» Pain
» +/- pyrexia
» +/- inappetence
» Causes:
* Migrating infection from oral
cavity (Staphylococcus, E.coli)
* Foreign body
* Haematogenous spread
Retrobulbar Abcess/ Cellulitis
- Palpebral swelling
- Conjunctival hyperaemia
- Prominent nicitans gland
Orbital Cellulitis Tx
Drainage
- Intubated w cuffed ET tube, pack throat
- Incise oral mucosa caudal to last upper molar
- Insert closed haemostat, slight open haemostat and withdraw
Systemic Ab - broad spec
Ocular Maintenance
- Ocular lubricants
- Topical ABs
Orbital Neoplasia
» Chronic, unilateral exophthalmos
» Nictitating membrane protrudes
» Blood vessel engorgement no
inflammation
» No periocular swelling
» Not normally painful or pyrexic
» Older
