Uveal Conditions Flashcards
Hyperpigmentation - Is the lesion…
6 points
1) Raised (casts shadows) – 3D
2) Increased vascular supply
3) Distorting surrounding tissues
4) Releasing pigmented cells (flare)
5) Assoc w 2° glaucoma
6) Assoc w leukoma
Uveal Neoplasia
1° = adenoma/carcinoma
2° = lymphosarcoma
Consider - glaucoma, uveitis, retinal detachment or h+
Arise from iris and ciliary body
Dogs = ~benign
Metastasise to oral cavity, toes, skin
2° Neoplasia - Lymphoma
- Ocular involvement (anterior uvea) = multicentric lymphoma
- Mimic hypopyon
- Hyphaema and generalized lymphadenopathy
- Diagnosis: neoplastic cells in peripheral blood sample, FNA of Lnn, organ or anterior chamber, bone marrow aspirates or biopsies.
- Treatment: Chemo and symptomatic treatment for ocular symptoms are therapeutic approaches.
Intra-ocular Melanoma - Cats
- > 10 yrs
- Locally invasive and high metastatic rate * Diffuse growth
- Pupil mobility affected
- 63% metastasize
Intra-ocular Melanoma - Dogs
- Average age 9yrs
- GSD and Retrievers
- Nodular growth
- Metastasize haematogenously
- Low risk of metastasis <6%
Adenomas and Adenocarcinomas
*The second most common neoplasm seen in dogs’ eyes.
*These generally appear as a single mass protruding from behind
the iris into the pupil.
*Can be pigmented or non-pigmented.
*Adenocarcinomas frequently infiltrate into the anterior iris and can cause secondary glaucoma by blocking the drainage angle
*Adenomas usually are limited to the ciliary body. *Adenocarcinomas tend to be pink
*Metastasis is highly unusual
Uveal Neoplasia Results in:
- 2° glaucoma
- Uveitis or endophthalmitis
- Hyphaema or vitreal
haemorrhage - Change in iris colour
- Collapse of the anterior chamber
- Erosion through the sclera to form staphyloma
- Distortion of the pupil
Intraocular Neoplasia - Diagnosis
ophthalmoscopy, tonometry, slit-lamp biomicroscopy, gonioscopy ultrasonography, other imaging modalities, anterior chamber centesis and cytology, biopsy.
Intraocular Neoplasia - Tx
- Contingent on tumour behaviour, size, pigment content, visual potential of the eye
- Also depends on species (e.g. iris melanomas in cats generally more malignant and rapidly progressive in
cats than dogs, so early enucleation often appropriate) - Some are amenable to diode or Nd:YAG laser photocoagulation (referral)
- Local excision for some small, well circumscribed tumours by iridectomy or iridocyclectomy (referral)
- Enucleation recommended where there is secondary glaucoma or uveitis/ where the tumour is large
- Exenteration recommended when there is extrascleral extension
- All enucleated eyes should ideally be submitted for histopathology
Uveal Cysts
- Remnants of optic vesicle
- Transilluminated
- Distinguish from tumour on ultrasound
- Spherical or ovoid
- Golden retrievers: assoc w glaucoma; inheritance…
*Clear / pigmented, fluid filled
*Location: Pupil margin / free floating/ attached to CB/ within the stroma
Causes of Hyphaema
- Trauma
- Fragile iris blood vessel walls
- Clotting disorders, platelet disturbances, dyscrasias, liver disease, DIC
- Neovascularization of the iris or retina [CEA]
- Vascularised tumours
- Systemic hypertension
- Hyperviscosity syndrome
- Severe uveitis
- Retinal dysplasia and rupture of vessels
- Systemic disease (e.g. Ehrlichia canis)
- Chronic glaucoma
- Post cataract surgery (a few months later, following neovascularization and blood vessel rupture).
- Spontaneous
Hyphaema - Complications
- glaucoma
- synechiae
- cataracts
- phthisis bulbi
- corneal edema / staining
Hyphaema - Diagnosis
Clinical signs
Ultrasound to determine vitreal involvement / retinal detachment
Hyphaema - Tx
Cage rest
Corticosteroids
Mydriacyl / Atropine
Monitor glaucoma
Uveal Inflammation
*Anterior uveitis
- Iris + ciliary body
*Posterior uveitis
- Choroid
*Panuveitis = All 3
Can be localized: iritis, cyclitis, pars planitis or choroiditis
Exudates:
o Serous - protein: Aqueous flare
o Fibrin: Fibrin clot
o Sanguineous: Hyphema
o Purulent: Hypopyon
Causes of Uveitis - Dogs/Cats
Infectious
Immune mediated
Metabolic
Misc
Uveitis - Ddx
*Ulcerative keratitis
*Acute glaucoma
*Acute conjunctivitis
*Episcleritis
Lens Induced Uveitis
*Phacoclastic uveitis
massive release of lens proteins capsule injury
severe uveitis in 6-10days
Rx: lens removal
Phacolytic uveitis gradual release
diabetic & hypermature cataracts Treatment: corticosteroids / NSAID life long
Uveitis - Clinical Signs
Aqueous flare
Aqueous flare/ Tyndall phenomenon
* 1+ - barely visible
* 2+ - moderate flare ( iris + lens details are clear)
* 3+ - marked flare ( iris + lens details are hazy)
* 4+ - intense flare (fixed, coagulated aqueous humour with fibrin)
Uveitis - Clinical Signs - Fibrinous aqueous
Fibrinous aqueous
* Acute severe anterior uveitis
* Lipid-concurrent hyperlipidaemia
Uveitis - Clinical Signs - Hyphaema
▪ Hyphaema
* Layeringinhyphaemaindicatesre-bleeding
Uveitis - Clinical Signs - Hypopyon
▪ Hypopyon
* Sterile inflammation * Infection
* Neoplasia
* ‘CiliaryFlush’
Uveitis - Clinical Signs - Corneal oedema
- ↑ in endothelial permeability + ↓ in Na/K-ATPase pump
- Formation of prostaglandins > free oxygen radicals, hydrolytic enzymes
Uveitis - Clinical Signs - Keratitic Precipitates
- Accumulation of cells, fibrin + pigment from iris –
deposit on corneal endothelium - Inferiorly ( current - warm iris – cooler cornea
