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KERATOPATHIES IN CARNIVORES: CLINICAL SIGNS AND LOCAL
PATHOLOGIC RESPONSES
IOANA BURCOVEANU, I. BURTAN, ROXANA TOPALĂ,
L.C. BURTAN, M. FÂNTÂNARIU
University of Agricultural Sciences and Veterinary Medicine, Iasi
ioana.burcoveanu@gmail.com
The cornea is the perfectly transparent, avascular, anterior component of the fibrous,
outer coat of the eye, along with the opaque, posterior sclera. Corneal pathology varies
from congenital disorders to tumors, primary or by extension. Keratitis define the
inflammation of the cornea, that may have numerous causes, like trauma, noninfectious
(physical, chemical) or infectious (bacterial, viral, fungal, parasitic) agents, immune
reactions. Acquired corneal pathology may be categorized as ulcerative or
nonulcerative, infectious or noninfectious, or by cause, topography, depth, etc.
Clinical signs can also vary greatly. Generally, we observe blepharospasm, photophobia,
hyperemic conjunctiva, epiphora, serous or mucopurulent discharge that clings to the
ocular surface. Because of its compact construction, pathologic reactions in the cornea
tend to evolve differently, regarding their speed of onset and recovery. The majority of
clinically important keratopathies develop one or more of the following local signs:
edema, vascularisation, pigmentation, cellular infiltrates, accumulation of lipid or
mineral material in the stroma and corneal fibrosis, with scar formation.
Optimal aetiologic diagnosis and clinical management require knowledge of the clinical
signs listed above.
Key words: cornea, keratopathies, symptoms, carnivores
The cornea is the perfectly transparent, anterior component of the eye, playing the role of a
convex ‐concave lens. It has no blood vessels or pigments, its thickness varying in animals
from 0,56 to 1 mm (0.5 – 0.8 mm) (5), becoming less thicker at the perifery in dogs and cats
(4). The posterior part of the outer, fibrous coat of the eye is the sclera. The point at which the
cornea and sclera merge is called the limbus (1, 3, 4, 5). The cornea plays many roles, such as:
mechanical, optical, immunological and tissue healing. (4)
From outside to inside, the cornea has 5 layers: epithelium, its basement membrane
(Bowman), stroma, Descemet’s membrane, endothelium (posterior epithelium). It is avascular
and it has no pigments, but it has a sensitive innervation, provided by nasociliary nerves of the
ophthalmic branch of the trigeminal nerve (cranial nerve V) (3, 5). The density of terminal
nerves is higher in the center and lesser at the periphery of the cornea.
The cornea is the first barrier of the globe, being exposed to exogenous disorders (trauma),
endogenous factors (corneal dystrophies, which are inherited) or to the extension from other
ocular tissues (anterior lens luxation, uveitis, neoplasia).
The present paper resumes the symptoms of clinically important keratopathies:
blepharospasm, epiphora, conjunctival hyperaemia, as well as the major pathologic responses:
corneal edema, vascularisation, fibrosis (scar formation), melanosis, accumulation of an
abnormal substance within the cornea (lipid, mineral), stromal malacia.
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