D-shaped pupil in cats
how to diagnose diseases from the eye
FeLV ( feline leukemia virus )
About 3.5 to 5.8% of outdoor cats is reported with this virus
Ocular changes linked to FeLV are related to the ability of the virus to induce immunosuppression, hematologic changes and tumor formation, retinal dysplasia, retinal hemorrhages and pupillary changes
Abnormalities in pupil shape due to FeLV include spastic pupil, D-shaped pupil and reversed D shaped pupil.
Cats have short ciliary nerves in the both sides of the eye
These “short ciliary nerves”
contains parasympathetic and sympathetic nerve fibers, when a cat is infected with FeLV, the virus make a damage to the parasympathic fibers in one side of the short ciliary nerves, which are responsible for contraction of ciliary body and iris.
- So when one side of the short ciliary nerves is damage, and the iris want to contract, it will contract from only one side
leaving the pupil with D shape or reverse D shape.
- But it’s not the way to diagnose FeLV, you should do other tests to make sure as ELISA test
