Miosis: When your pupil shrinks

When your pupil shrinks (constricts), it's called miosis. If your pupils stay small even in dim light, it can be a sign that things in your eye aren't working the way they should. Inherited congenital microcoria, also referred to as congenital miosis, is characterized by bilateral small pupils (diameter less than 2 mm) that result from an underdevelopment of the dilator pupillae muscle of the iris (Holth and Berner, 1923; Simpson and Parsons, 1989). Iris transillumination defects are a constant feature. Miosis occurs naturally when doing close work or when stimulated by light. Note: also spelt myosis. See corneal reflex; pupil light reflex; baring of the blind spot; Horner's syndrome. Eye Miosis: Symptoms, Causes, Diagnosis, and Treatment Eye miosis is the constriction of the pupil, resulting in smaller-than-normal pupils. While pupil constriction is a natural response to bright light or near-focus, persistent or abnormal miosis may indicate an underlying health condition. In this article, we will explore the causes, symptoms, diagnosis, and treatment options for eye miosis, helping you understand its significance and how to manage it effectively.