Page 1308 - Problem-Based Feline Medicine

1300 PART 15 CAT WITH EYE PROBLEMS

Treatment Spastic pupil syndrome is associated with FeLV neuri-
tis. Vision is retained, but one or both pupils are inter-
There is no treatment for iris atrophy.
mittently miotic or dilated over weeks or months, and
they do not dilate appropriately with darkness. For more
FELINE LEUKEMIA VIRUS (FELV)** detail see main reference on page 878 (The Cat With
Anisocoria or Abnormally Dilated or Constricted Pupils).
Classical signs
Diagnosis
● Discrete iris or ciliary body masses (FeLV-
associated lymphosarcoma). Diagnosis is based on the clinical signs observed in the
● Anterior uveitis, fibrin and blood in the eye, in association with other signs suggestive of FeLV,
anterior chamber. e.g. multicentric lymphoma, FeLV-associated anemia.
● Otherwise unexplainable intermittent Diagnosis is confirmed on clinical pathology includ-
asymmetric changes in pupil size, shape or ing hematology and cytology of lymph nodes or aque-
response. ous centesis samples which demonstrate neoplasia.
● Other FeLV-associated signs, e.g. anemia.
A positive serological test for FeLV antigen suggests
See main references on page 540 for details (The association of the neoplasm or spastic pupil syndrome
Anemic Cat) and page 350 (The Thin, Inappetent Cat). with FeLV infection. For more details of testing see
main reference on page 543 (The Anemic Cat).

Pathogenesis Treatment
Following oral or nasal exposure to the virus, there is For more detail see main reference on page 544 (The
viral replication in oropharyngeal lymphoid tissue. Anemic Cat)
If the immune response to the virus is ineffective in
eliminating it, there is replication of virus in bone Treatment of the ocular condition in conjunction with
marrow, which leads to viremia, FeLV-related diseases systemic chemotherapy might include topical corti-
or latent infection. costeroids such as 0.5% prednisolone acetate drops
given q 6–12 h. Prognosis for the eye will be poor to
Infection with the virus is known to cause a number of guarded if secondary glaucoma has occurred.
neoplasms, including alimentary, mediastinal, renal,
spinal, retrobulbar or lymph node forms as well as a
number of hematologic lymphoid malignancies involv- FUNGAL INFECTIONS** (CRYPTOCOCCUS
ing different bone marrow precursors. NEOFORMANS, BLASTOMYCOSIS,
COCCIDIOIDOMYCOSIS, HISTOPLASMA
Malignant lymphoid cells can invade intra-ocular CAPSULATUM)
uveal structures, generally as part of a wider syndrome
of multicentric lymphosarcoma. Classical signs
A viral neuritis can also be caused by FeLV, and affect ● Chorioretinitis progressing to anterior
parasympathetic or sympathetic efferent fibers to the uveitis and endophthalmitis, occurring in
iris in feline spastic pupil syndrome. a geographical area where fungal
FeLV is also associated with uveitis. infections are known to occur.
● Vision loss and reduced pupil light reflexs
in affected eyes.
Clinical signs ● Signs of other organ system disease, e.g.
renal, CNS, nasal cavity.
Discrete iris or ciliary body masses, which cause gross
distortion of iris structure, and are usually bilateral.
See main references on page 16 for details (The Cat With
Fibrin and/or blood may be evident in the anterior Signs of Chronic Nasal Disease) for cryptococcosis and
chamber indicating the presence of anterior uveitis. pages 371, 379, 387 (The Pyrexic Cat) for other fungi.