Page 1187 - Problem-Based Feline Medicine

57 – THE BLIND CAT OR CAT WITH RETINAL DISEASE 1179

nerves fibers. The resulting retinal degeneration asymmetric changes in pupil size, shape or response.
results in the following ophthalmoscopic signs: For more detail see main reference on page 1278 (The
● A hyper-reflective tapetum. Cat With Abnormal Pupil Size, Shape or Response).
● Attenuation (thinning) of the retinal blood vessels.
It is possible to see retinal detachment when the neo-
● Optic disc cupping (the optic disc is pushed back-
plastic process involves the choroid.
ward).
There may be other signs of FeLV-associated disease,
e.g. anemia or multicentric lymphosarcoma.
Diagnosis
Diagnosis is based on the clinical appearance of Diagnosis
buphthalmos, with any or all of the other related signs
of glaucoma, such as chronic anterior uveitis and lens Diagnosis is based on the clinical signs observed
instability. in the eye, in association with other signs suggestive of
● Tonometry is used to measure intra-ocular pressure FeLV, e.g. multicentric lymphoma, FeLV-associated
(IOP). Normal range for IOP in the cat is anemia.
15–25 mmHg. Readings over 30 mmHg are sup- Diagnosis is confirmed on clinical pathology, for exam-
portive of a diagnosis of glaucoma. ple on cytology of lymph nodes or aqueous centesis
samples, or occasionally on hematology.
A positive serological test using an antigen-based test
FELINE LEUKEMIA VIRUS for FeLV is supportive evidence of the disease. For more
detail see main reference on page 543 (The Anemic Cat).
Classical signs
● Discrete iris or ciliary body masses (FeLV- Treatment
associated lymphosarcoma).
● Anterior uveitis. For more detail see main reference on pages 1292 and
● Intermittent asymmetric changes in pupil 544 (The Cat With Abnormal Iris Appearance and The
size, shape or response. Anemic Cat).
● Other FeLV-associated signs, e.g. anemia.
Treatment of the ocular condition, in conjunction with
● Retinal detachment.
systemic chemotherapy, might include topical cortico-
steroids such as 0.5% prednisolone acetate drops given q
See the main reference on page 1300 (The Cat With
6–12 h.
Abnormal Iris Appearance).
Prognosis for the eye will be poor to guarded, if sec-
ondary glaucoma has occurred.
Clinical signs

FeLV may cause ocular lymphosarcoma, which ap-
pears as discrete iris or ciliary body masses, usually FELINE INFECTIOUS PERITONITIS VIRUS
bilateral, which may cause gross distortion of the iris
structure. Classical signs
FeLV more commonly presents as a uveitis, with changes ● Young cats 6–12 months of age.
to iris appearance, and abnormal pupil size and shape. ● Anterior uveitis with large fibrin clots
The anterior chamber may contain fibrin and/or (hypopyon).
blood. Anterior uveitis may occur in the absence of ● Keratic precipitates (“mutton fat deposits”)
discernible intra-ocular neoplasia. on the cornea.
● Chorioretinitis causing variable vision loss
Some cats develop spastic pupil syndrome, which
and/or abnormal pupil reflexes.
presents as otherwise unexplainable intermittent
(continued)