What is mydriasis commonly defined as?

Mydriasis is defined as the condition where the pupil is larger than normal or dilated. This can occur due to various factors, including physiological responses to low light levels, sympathetic nervous system stimulation, or the influence of certain medications and substances. Understanding mydriasis is crucial in veterinary ophthalmology because it can indicate underlying health issues or reactions to anesthesia or medications that require attention.

The other options describe different conditions: a small or constricted pupil refers to miosis, while a cloudy lens pertains to cataracts, and not mydriasis. Recognizing the specifics of pupil size and its clinical significance is essential for accurate diagnoses and treatment in veterinary patients.