Page 1238 - Problem-Based Feline Medicine

1230 PART 15 CAT WITH EYE PROBLEMS

a tentative diagnosis of herpetic keratitis. Close exam- Diagnosis
ination will show dendritic lesions or geographical
Diagnosis is based on the clinical signs of severe
ulceration.
ocular pain with a serous discharge, and evidence of
Laboratory tests such as PCR may support a diagnosis of corneal trauma, such as a tear in the cornea, which may
FHV-1 infection. See Herpetic conjunctivitis, page 1213. be plugged with fibrin, or have an iris prolapse.
Ocular discharge which will vary from serous to very
CORNEAL TRAUMA*** watery, if aqueous is leaking.

Classical signs
ULCERATIVE KERATITIS**
● Blepharospasm and photophobia with
ocular guarding.
Classical signs
● Initially a serous ocular discharge
becoming mucopurulent. ● Painful closed eye with a serous discharge.
● +/- Copious watery discharge from ● Focal or diffuse corneal cloudiness.
constant leakage of aqueous humor if ● Conjunctival inflammation.
cornea is perforated. ● Corneal erosion.
● Blue or cloudy cornea. ● Positive green stain with fluorescein dye.
● Retention of fluorescein stain. ● Red appearance of cornea in chronic cases.
● Black appearance to the corneal deficit,
if iris is prolapsed through wound. See main reference on page 1246 for details. (The Cat With
Abnormalities Confined to the Cornea).
See main reference on page 1249 (The Cat With
Abnormalities Confined to the Cornea).

Clinical signs
Clinical signs
Serous ocular discharge is often the presenting sign.
Ocular pain is evident as blepharospasm and photo-
phobia. Signs of ocular pain with blepharospasm (resulting in
a closed eye), and photophobia are present.
There will be an ocular discharge, which is serous at
first and becomes mucopurulent. Focal or diffuse corneal edema (cloudiness) occurs,
depending on the amount of epithelial loss.
In cases where the cornea is perforated, there may be
a copious watery discharge from constant leakage of Erosion of epithelium and stroma is present, depending
aqueous humor out of the wound. on severity of the ulceration.
The surrounding cornea will have corneal edema seen There will be retention of fluorescein stain by the
as a blue or cloudy eye. exposed corneal stroma.

There will be retention of fluorescein stain where Chronic cases may show varying degrees of vascular-
there is a large deficit of epithelium. If the wound is ization.
leaking aqueous, the fluorescein will wash off the
Large ulcers usually develop corneal vasculariza-
cornea away from the perforation.
tion, which may be superficial or deep, and result
Fibrin tags or clots may be seen attached to the injured in a red appearance of the cornea. This depends on
area of the cornea, plugging the wound. how long the ulcer has been present, and what the
cause is.
In large perforations, iris tissue may be prolapsed (iris
prolapse) through the wound giving a black appearance The eye may be red because of conjunctival inflam-
to the corneal deficit. mation.