CHAPTER 43 The Eye
The Ophthalmic Examination
BOX 43-1 Normal features of the immature canine and feline eye
Eyelids | Separate at 10-14 days |
Globe position | Kittens demonstrate subtle divergent strabismus until 3-4 weeks |
Tear film | Reflex tearing is present when eyelids separate |
Cornea | Mild corneal edema begins to clear within 24 hours after eyelids open; corneal thickness continues to decrease until 6 weeks of age |
Iris | Newborn blue-gray iris shows signs of adult coloration by 1 month of age; persistent pupillary membranes are seen until 6 weeks of age in puppies and 3 weeks of age in kittens |
Lens | Vessels of the tunica vasculosa lentis are seen until 4 weeks of age |
Fundus | The blue-gray tapetum gradually assumes adult coloration by 4 months of age; the optic disc appears smaller because of incomplete myelination, but caliber and distribution of retinal vessels are similar to adult |
Vision/menace reflex | Visual reflexes are poor at 3 weeks of age, gradually improving until 6-8 weeks of age, as retina continues to differentiate |
Pupillary light reflexes | Present within 24 hours of lid separation but sluggish until the retina matures during week 4 |
Dazzle reflex | Present when eyelids open |
The Globe and Orbit
The Eyelids
Congenital Abnormalities
Eyelid Agenesis

Figure 43-3 Eyelid agenesis. The superior temporal lid margin is absent in this 6-month-old Domestic Shorthair cat.