This document outlines various ocular manifestations of systemic diseases in dogs. It discusses cardiovascular issues like hypertension and how they can cause retinal hemorrhages. Hematologic disorders like anemia, thrombocytopenia, and hypertriglyceridemia are covered. Neurologic conditions such as granulomatous meningoencephalitis can lead to blindness. Dermatologic diseases including autoimmune disorders and demodex mites are addressed. Infectious diseases from ticks, parasites, fungi and more are outlined. Endocrine conditions like diabetes and hypothyroidism are discussed. Finally, oncologic topics like lymphoma and other metastatic cancers to the eyes are summarized.

1. Dr. Christa Corbett, DVM, MS, DACVO
September 17, 2016

2. Outline
 Cardiovascular
 Hematologic
 Neurologic
 Dermatologic
 Internal medicine
 Infectious disease
 Endocrine
 Oncologic

3. CARDIOVASCULAR

4. Systemic hypertension
 Pathogenesis:
 Ischemic necrosis of vessel walls =
increased vascular permeability
 Patient variation is important to remember,
but a sustained systolic BP >180 mmHg will
lead to end organ damage

5. Systemic hypertension
 Ophthalmic signs:
 Retinal vascular tortuosity (occasionally)
 Hemorrhages
○ Retinal is most common
○ Subconjunctival
○ Iris stroma
○ Hyphema
 Retinal edema or detachment
 Treatment is targeted at the
underlying disease

6. HEMATOLOGIC

7. Anemia
Does not commonly lead
to ocular disease (~10%)
Ophthalmic signs:
 Conjunctival pallor
 Focal retinal hemorrhages
○ Due to tissue hypoxia of the
vascular walls

8. Thrombocytopenia
 Commonly causes ocular disease
 25% have mild ocular signs (focal hemorrhages)
 16% have severe ocular signs (hyphema)
 Ophthalmic signs:
 Hemorrhages:
○ Retinal is most common
○ Subconjunctival
○ Iris stroma
○ Hyphema
 Treatment is targeted at the
underlying disease

10. Hypertriglyceridemia/
Hyperlipidemia
 Primary (familial)
 Miniature schnauzer, Beagle, Briard, Collie, and Sheltie
 Anecdotally in the Capital District  Miniature
Pinschers
 Secondary (secondary to other systemic
disease)
 Hypothyroidism, Diabetes, Pancreatitis
most common
 Cushings, renal or hepatic diseases also
rarely possible

11. Hypertriglyceridemia/
Hyperlipidemia
 Ophthalmic signs:
 Lipemia retinalis
 Lipemic aqueous
 Corneal lipid

12. Hypertriglyceridemia/
Hyperlipidemia
 Ophthalmic signs:
 Lipemic aqueous
○ Must have alteration in blood-aqueous barrier
(uveitis, intraocular surgical patients)
○ Chicken or egg  Uveitis started and lipids
leak, or intravascular lipemia causes vascular
endotheliitis and increased permeability

13. Lipid plaques just about
anywhere!

14. Hypertriglyceridemia/
Hyperlipidemia
 Treatment:
 Treat underlying disease
 Thorough diet history
○ (ask the same questions
3-5 times sometimes!!!)

15. Hypertriglyceridemia/Hyperlipid
emia
 STRICT low fat diet
○ Royal Canin Gastrointestinal Low Fat
 Study by Xenoulis et al JVIM 2011
 Less than 25g of total fat per 1000 kcal
○ Nutritionist for a low nutritionally balanced fat
home cooked diet (U of Tenn)
○ Fruits and Vegetables for treats
 Lipid binding agents
○ All off-label (as of 2014)
○ Omega-3 fatty acids, Fibrates (Gemfibrozil),
Niacin

16. Hyperviscosity
 Causes:
 Multiple myeloma, lymphoma,
CLL, ehrlichiosis
 Ocular findings:
 Dilated, tortuous retinal vessels
 Perivascular edema or infiltrate
 Retinal hemorrhages (along small arterioles)
 Treatment is targeted at the underlying
cause

17. NEUROLOGIC

18. Granulomatous
Meningoencephalitis
 Suspect immune-mediated inflammation of
the meninges and/or brain
 Optic nerve (+/- retinal) involvement =
blindness, mydriasis
 Ophthalmic findings:
 Blindness
 Mydriasis
 Papilledema
 Peripapillary hemorrhages
 Rarely retinal infiltrate or
detachment

19. Granulomatous
Meningoencephalitis
 Diagnosis:
 Neurologic work-up including MRI and CSF
 Treatment:
 Systemic immunosuppression
○ Steroids AND Cystosine arabinoside,
Azthioprine, Leflunomide or Cyclosporine

20. DERMATOLOGIC

21. Autoimmune dermatitides
 Pemphigus complex diseases
 Discoid lupus erythematosus
 Systemic lupus erythematosus
 All can lead to facial dermatitis
characterized by erosions,
ulcers, crusting, scaling and
depigmentation

22. Parasitic dermatitides
 Demodex
 Ophthalmic findings:
○ Alopecia, scaly skin around eyes, lips and
forelegs
○ Rarely pruritic unless secondary bacterial
involvement
 Sarcoptes
 Rarely periocular

23. Uveodermatologic
Syndrome
 Aka Vogt-Koyanagi-Harada or VKH-
like syndrome
 Human version also linked to hearing
loss and meningitis
 Immune-mediated destruction
of melanocytes
 Akita is the top breed, but has
been reported in dozens of
others

24. Uveodermatologic
Syndrome
 Ophthalmic findings:
 Anterior uveitis
 Chorioretinitis with varying severity
○ Focal regions of subretinal exudate
○ Retinal detachments
 Loss of choroidal pigment
 Dermatologic findings:
 Vitiligo (skin depigentation) and
poliosis (hair depigmentation)
○ Often restricted to face
○ Can be ulcerative in nature

25. Uveodermatologic
Syndrome
 Diagnosis:
 Biopsy of tissue
○ Enucleation if glaucomatous and blind
○ Dermal biopsy of facial mucocutaneous
junctions

26. Uveodermatologic
Syndrome
 Treatment:
 Systemic immunosuppression
 Steroids AND Azthioprine, Mycophenolate or
Cyclosporine
 Topical anti-inflammatories for anterior
uveitis
 Prednisolone acetate AND Diclofenac in most
cases
 +/- Glaucoma medications

27. June 26, 2009
September 15, 2009

28. June 26, 2009
September 15, 2009

29. INTERNAL MEDICINE –
Infectious disease

30. Tick-Borne disease
 Lyme
 3% incidence of ocular disease in 132
seropositive dogs
 Ophthalmic findings:
○ Conjunctivitis
○ Corneal edema
○ Anterior uveitis
○ Retinal petechia
○ Chorioretinitis
○ Retinal detachment
○ Orbital disease

31. Tick-Borne disease
 Anaplasma
 A. platys = Canine Cyclic Thrombocytopenia
○ Ophthalmic findings:
 See findings associated with Thrombocytopenia

32. Tick-Borne disease
 Ehrlichia
 Ocular lesions can occur in any stage of
disease, mostly with E. canis
 10-37% of cases have ocular signs
 Ophthalmic findings:
○ Thrombocytopenia findings
○ Vasculitis lesions
 Anterior or posterior uveitis

33. Tick-Borne disease
 RMSF
 81% of cases have ocular signs
 Ophthalmic findings:
○ Thrombocytopenia findings
○ Vasculitis lesions
 Anterior or posterior uveitis

34. Parasitic disease
 Toxoplasma
 Rarely causes ocular disease in dogs
 Ophthalmomyiasis
 Fly larvae penetrate into the eye
○ Conjunctival extension
○ Penetrating trauma?
 May see actual larvae, or can
see chronic tracts

35. Parasitic disease
 Ophthalmomyiasis
 Subclassifications:
○ Externa = Orbital and extraocular
○ Interna anterior = larvae in anterior chamber
○ Interna posterior = larvae in posterior segment
 Treatment:
○ Manual removal if possible
○ Organophosphate treatment is controversial,
as dead larvae can incite more inflammation

39. Fungal disease
 Aspergillus
 Local disease (nasal mucosa and respiratory)
unlikely to cause ocular disease
 Disseminated disease can lead to panuveitis,
chorioretinitis and retinal detachment
 Coccidiomycosis
 Southwestern US
 Panuveitis with disseminated
disease
 Often unilateral

40. Fungal disease
 Cryptococcus
 Not very common in dogs
 Granulomatous to
pyogranulomatous chorioretinitis
with or without exudative retinal
detachment
 Optic neuritis possible

41. Fungal disease
 Histoplasma
 Chorioretinitis most common, possibly
extension to anterior uvea
 Optic neuritis

42. Fungal disease
 Blastomycosis
 Ocular involvement in 48% of cases
 Ophthalmic findings:
○ Often begins posterior, so early ocular stages
aren’t often noted
 Hematologic spread to the fine capillaries of the
choroid
 Mild = focal subretinal granuloma
 Severe = exudative retinal detachment
○ Anterior uveitis is often due to
endophthalmitis, organisms are
often not found in anterior uvea

43. Fungal disease
 Blastomycosis
 Diagnosis:
○ Urine blasto antigen (MiraVista)
○ Cytology or biopsy of tissue
 Subretinal or vitreous aspirate,
enucleation, or biopsy of another
distant lesion
○ Serology:
 AGID test
- 67% sensitivity
- 100% specificity

44. Fungal disease
 Blastomycosis
 Treatment:
○ Long-term azole antifungals (itraconazole has
80% clinical cure rate)
 Recurrence is common, can be years later
○ +/- oral steroids
 Not reported to worsen survival, and may help ocular
disease
○ Topical anti-inflammatories
○ +/- Glaucoma meds

45.  Enucleation???
○ Often recommended for blind, painful eyes
○ NO proof that the eye can sequester
organisms, so enucleation is considered
palliative for pain control, but not essential for
survival

47. INTERNAL MEDICINE –
Endocrine

48. Diabetes
 Ophthalmic findings:
 Cataract
 Corneal endothelial cell loss
 Retinal vascular damage and hemorrhage
○ Note: NOT the same as the proliferative
diabetic retinopathy in humans
 Decreased corneal sensitivity
 Low schirmer tear test

49. Hypothyroidism
 Ocular symptoms not directly caused by
hypothyroidism, but associated conditions:
 KCS
○ Multi-glandular immune-mediated inflammation?
 Hyperlipidemia can lead to corneal lipid
degeneration, lipemic aqueous
or lipemia retinalis
 Neurologic signs
○ Horner’s, Facial paralysis

50. ONCOLOGIC

51. Lymphoma
 Most common metastatic intraocular
tumor
 37% of lymphoma cases present with
ocular disease
 Anterior uveitis – 49%
 Posterior uveitis – 9%
 Panuveitis – 14%
 Retinal hemorrhage – 23%
 Adnexal disease – 6%

52. Lymphoma
 Most common metastatic intraocular tumor
 37% of lymphoma cases present with
ocular disease
 Anterior uveitis – 49%
 Posterior uveitis – 9%
 Panuveitis – 14%
 Retinal hemorrhage – 23%
 Adnexal disease – 6%
 Ocular involvement makes this
Stage 5, so shorter survival

53. Other metastatic disease
 Mostly carcinomas and sarcomas
 Malignant melanoma (i.e. ungual)
 Transmissible venereal tumor
 Ophthalmic findings:
 Hyphema
 Uveitis
 Glaucoma

54. Questions???