This is MIOSIS, which means that the irises are small and contricted. This dog also has sectoral heterochromia in the upper left iris, which is just a fancy way to say different colored parts of the iris.In contrast, mydriasis means dilated pupils. You can see mydriasis almost every day in a small animal clinic, when treating an animal with atropine and glycopyrrolate.These anticholinergic drugs are commonly given before routine surgeries as PREANESTHETICS, to prevent bradycardia and dry up airway secretions.Glaucoma and proptosis are ophthalmic emergencies: glaucoma is increased intra-ocular pressure, and proptosis means the globe of the eye is poking out. Without rapid treatment, the pet is likely to lose sight in the affected eye.Ptosis means a drooping eyelid.Refs: Papich, Saunders Handbook of Vet Drugs: Sm & Lg An., 4th ed. p. 61, 361 and Cohn and Cote, Clinical Vet Advisor – Dogs and Cats, 4th ed. pp. 387-9. Image courtesy of Olga Petersen.