The Cloudy and the Red Eye

Question 1

You are presented with a dog with a cloudy eye, you believe you have localized it to the cornea and are between a corneal ulcer or endothelial dysfunction based on its appearance (fairly homogenous cloudiness), what diagnostic test can help you distinguish between those two options?

Answer 1

(Fluorescein stain)

Question 2

You are presented with a dog with a cloudy eye that you believe you have localized to the cornea and it has a relatively homogenous, diffuse presentation with some faint stippling (you might say it looks like ground glass), the dog is non-painful and fluorescein stain negative, what is your top differential?

Answer 2

(Endothelial dystrophy/degeneration)

Question 3

What are your differentials for a homogenous, focal cloudiness of the cornea?

Answer 3

(Corneal scar/fibrosis, corneal ulcer or an anterior lens luxation causing focal edema)

Question 4

What are some causes for chronic abrasions of the eye resulting in corneal scars/fibrosis?

Answer 4

(Entropion, distichia, ectopic cilia)

Question 5

What are some causes for chronic exposure of the eye resulting in corneal scars/fibrosis?

Answer 5

(Lagophthalmos and KCS)

Question 6

What are the two causes for lipid keratopathy?

Answer 6

(Lipid dystrophy and lipid degeneration)

Question 7

What can cause lipid degeneration that can then result in lipid keratopathy? 4 answers.

Answer 7

(Prior keratitis, infiltrative corneal dz, topical corticosteroid use, and systemic metabolic dzs such as cushings, diabetes, hyperthyroidism, and primary hyperlipidemia)

Question 8

What is the typical presentation of a dog affected by lipid dystrophy?

Answer 8

(A young dog with bilaterally cloudy, non-painful eyes; lesion of the eye will appear particulate with numerous coalescing small particles → may appear glittery/sparkly/refractile)

Question 9

If you note a sparkly lesion on the periphery of the cornea in an older dog who also has PU/PD and weight loss with an increased appetite, what is your top differential?

Answer 9

(Diabetes → lipid at the periphery of the cornea is often related to metabolic dz)

Question 10

Compare and contrast the appearance of corneal lipid and corneal mineralization?

Answer 10

(Similar → numerous coalescing particles; differences → corneal mineralization is spiculated and not shiny whereas corneal lipid is not spiculated and shiny)

Question 11

If a patient of yours has a cloudy cornea and they are painful, that narrows down your list of causes; describe what their cloudiness should look like on closer inspection and list the causes of that cloudiness.

Answer 11

(Edema > homogenous, maybe faintly stippled (if more chronic) focal (ulcer) to diffuse (uveitis/glaucoma); caused by an ulcer, anterior uveitis, or glaucoma)

Question 12

What clinical sign associated with uveitis can cause a cloudy eye, which you can diagnose by looking for the Tyndall effect with a slit lamp?

Answer 12

(Aqueous flare)

Question 13

What is the main way to distinguish between aqueous and lipemic flare? (Not a diagnostic test)

Answer 13

(Pain, unless the lipemic flare is caused by uveitis (which is possible) it will be painless, if it is caused by uveitis then it doesn’t really matter if its lipemic or aqueous, tx the uveitis)

Question 14

What is an easy diagnostic test you can run when you have a cloudy eye that you suspect is either aqueous or lipemic flare but you’re just not quite sure?

Answer 14

(Spin down a hematocrit tube → milky serum = lipemia, not milky serum = aqueous flare d/t uveitis)

Question 15

What are two causes of a cloudy lens?

Answer 15

(Nuclear sclerosis and cataracts)

Question 16

What is the main way to determine if a cloudy lens is d/t nuclear sclerosis versus a cataract?

Answer 16

(If the light can get through the cloudiness when using a distant direct ophthalmoscopy technique = nuclear sclerosis, if light cannot get through = cataract)

Question 17

What is asteroid hyalosis?

Answer 17

(A normal aging change (though can also be seen with intraocular masses) → calcium and phosphorus particulates in the vitreous fluid which is also starting to liquify)

Question 18

(T/F) In a case of conjunctival hyperemia, the location of the most severe hyperemia often suggests the location of disease.

Answer 18

(T)

Question 19

What are differentials for subconjunctival hemorrhage?

Answer 19

(Coagulation disorders, vasculitis, proptosis, trauma, and strangulation)

Question 20

What are differentials for hyphema? 6 answers.

Answer 20

(Retinal detachment, coagulation disorders, vasculitis, systemic hypertension, uveitis, and neoplasia)

Question 21

You are presented with a dog with an owner complaining of a red eye, you take a look and notice episcleral injection and mydriasis but no other abnormalities of the eye. What is at the top of your differential list and how would you definitively diagnose it?

Answer 21

(Glaucoma, tonometry)

Question 22

You are presented with a dog with an owner complaining of a red eye, you take a look and notice episcleral injection, diffuse conjunctival hyperemia, and miosis. What is at the top of your differential list?

Answer 22

(Uveitis)

Question 23

What are the most important immediate rule-outs for a red eye → you should not empirically treat an eyeball until you have ruled out these four diseases?

Answer 23

(Corneal ulcer, dry eye, glaucoma, and uveitis)