What does pupil dilation mean?

Pupil dilation can be caused by various factors: 1. Light changes: Pupils automatically adjust their size according to the intensity of ambient light. In dim environments, pupils dilate to allow more light to enter, thereby helping us see better in the dark. 2. Fright or injury: When suddenly startled or experiencing trauma, the body produces a series of stress responses, including pupil dilation. This enhances visual field and sensitivity, enabling better response to potential threats. 3. Eye diseases: Certain eye conditions such as glaucoma or iris atrophy may lead to pupil dilation. These diseases are usually accompanied by other symptoms, such as vision loss or pain. 4. Medication effects: Some medications, such as mydriatic agents like atropine, can cause pupil dilation. These drugs are commonly used during eye examinations or for treating specific eye disorders.