ophthalmic examination
retropulsion
orbital palpation
examination of facial symmetry
globe movement
oral exam
nasal airflow
retropulsion
should be equal
orbital palpation
bony changes
masses in orbit
periocular soft tissue swelling
examination for facial symmetry
globe position & alignment
globe movement
vestibulo-ocular reflex
direction of gaze
oral exam
restricted movement
pain opening mouth
oral mucosa
U/s
soft tissue masses within orbit
guide FNA or Bx
rads
skull or dental
req general anesthesia
good for bony lesions, radiodense FB
often non-dx
MRI/CT
MRI superior for soft tissue imaging
CT superior for detection of bony lesions
evaluates extent of disease
FNA/Bx
incisional bx
Tru-Cut
U/s guided
exploratory orbitotomy
various approaches
obtain sample for bx
diagnostic test for orbital disease
U/s
rads
MRI/CT
FNA/bx
exploratory orbitotomy
microphthalmos
congenitally small globe with concurrent ocular abn
differentiate from enophthalmos
often associated with dilute coat color
nonprogressive
no therapy
nanophthalmos
congenitally small globe without other abn
anophthalmos
congenital absence of globe
rare
cyclopia
Veratrum californicum toxicosis in sheep
day 14 in gestation
congenital anophthalmia, cyclopia and synophthalmia
strabismus
abnormal eye position
exotropia
eostropia
can be congenital or acquired
extropia
divergent
esotropia
convergent
congenital strabismus
Siamese cats
brachycephalic dogs
hydrocephalus
usually no therapy
acquired strabismus
neurological, inflammatory and fibrosing diseases
treat underlying cause
orbital cellulitis/abscess
common in SA
underlying cause often not found-FB, ascending tooth root inf, resp dz
orbital cellulitis/absces: Presentation
younger animals (avg 4 yo)
acute onset
unilateral exophthalmos, raised nictitans, periorbital swelling, decreased retropulsion
pain opening mouth!
lethargy, pyrexia, leukocytosis
orbital cellulitis/abscess: Dx testing
PE
Minimum database
FINA/bx
U/s
MRI
orbital cellulitis/abscess: Tx
drain abscess
1) incise oral mucosa posterior to last maxillary molar
2) gently insert hemostats and open (DO NOT CLOSE HEMOSTATS-nerves and aa nearby)
3) swab for C&S
4) Drain and flush
Broad spectrum abx, NSAIDs for weeks
Orbital neoplasia: presentation
older animals (avg 10 yo)
slower progression
unilateral sx
no pain opening mouth
PE and labs-normal
Orbital neoplasia: Dx testing
PE
Min DB
Bx
u/s
MRI**
orbital neoplasia: Px
guarded
usually malignant
often euthanized shortly after presentation
Horner's syndrome: causes
loss of sympathetic innervation to the eye
Idiopathic in dogs
Gutteral pouch disease in horses
trauma
otitis media
neoplasia
rare in cats
Horner's syndrome: clinical sxs
enophtalmos
raised third eyelid
ptosis (mueller's muscle)
miosis
horse-ipsilateral sweating
cow-ipsilateral absence of sweating on the noise
Horner's Syndrome: Localize the lesion
denervation hypersensitivity: postganglionic lesions, in absence of NT, muscle upregulates receptors-more sensitive
indirect sympathomimetic drugs: preganglionic-pupillary dilation, post ganglionic-minimal to no pupillary dilation
direct sympathomimetic drugs: Epi, pre-pupillary dilation 30-40 min, post, pupillary dilation <20 min
Horner's Syndrome: Dx & Tx
pharmacologic testing localizes the lesion
further workup based on results: Otic exam, MRI, thoracic rads
idiopathic-spontaneously resolves in ~6 weeks
other tx-depends on cause
post-better px
secondary enophthalmos
due to loss of orbital contents or dz of adjacent structures: weight loss, muscle atrophy
tx: underlying cause, secondary entropion, conjunctivitis
Phthisis bulbi
shrunken globe
secondary to chronic/severe infl, glaucoma
damage to ciliary body decreases and eventually stops aqueous humor production
differentiate from microphthalmos
enucleation
removal of globe, eyelid margins, conjunctiva and third eyelid
indications: blind, painful eyes, disease limited to the eye (ie galucoma, perforated globe, intraocular tumor)
exenteration
enucleation with removal of all orbital contents
indications: ocular disease extending beyond sclera (ie intraocular tumor with extrascleral extension)
evisceration
removal of ocular contents, leaving only cornea and sclera, followed with placement of prosthesis
indications: blind, painful eyes, disease limited to globe, caution with corneal disease
orbitotomy
exploratory or therapeutic
various techniques
varying levels of exposure