The results show that, in the right eye, average pupil size ranges from 2.41 to 5.80 millimeters in people ages 15 to 30 and from 2.38 to 4.52 millimeters in those over 60 years of age. One study measured pupil size at different light levels and across different age groups. In older adults, pupils are smaller when at rest in the dark and slower to dilate in response to light. During the teen years and throughout adult life, pupils shrink. In newborns, for instance, pupil size is much smaller, though size increases as a child grows, becoming largest in adolescence. Pupil size changes naturally with age - this is totally normal. In some cases, however, anisocoria can be a sign of a serious problem, such as a viral infection, an issue with the nervous system or an eye injury or condition. Pupils also typically get smaller when focusing on nearby objects and grow larger when focusing on faraway objects.īoth pupils may be the same size, but some people have pupils of different sizes ( anisocoria). Low light – Pupils normally constrict to between 2 and 4 millimeters in size. This size varies based on the amount of light in the environment:īright light – Pupils normally dilate to between 4 and 8 millimeters in size. Are my small pupils normal?Īverage sized pupils generally range from 2 to 8 millimeters. While your pupils normally open (dilate) in low light and grow smaller (constrict) in bright light, they also naturally get smaller as you age - this is not a sign for concern.īut, knowing more about whether your small pupils are normal or indicate a problem is key to understanding if you’ll need medical attention. With miosis, one or both pupils consistently measure less than 2 millimeters across.
This light is focused on the retina to allow eyesight.Ībnormally constricted pupils ( miosis), also known as pinpoint pupils, may be a sign of a larger issue with your health. Pupils naturally get larger and smaller thousands of times a day, regulating the amount of light that enters the eye. Living and Managementĭue to the nature of this medical condition, it is possible that it will continue to progress as your cat ages.The pupil is the opening in the center of the colored part of the eye ( iris). Iris atrophy is not reversible, so much of the treatment is designed to target the underlying disease that has caused it, or to halt the progression of the disease. The initial goal will be to differentiate iris atrophy from congenital iris anomalies, as there are a variety of other eye issues that can be the cause of the symptoms, such as ris aplasia (failure of the iris to develop normally), iris hypoplasia (underdevelopment or incomplete development of the iris), iris coloboma (a complete, full-thickness area of lack of development of all layers of the iris), and polycoria (when more than one pupil is present in a single iris within the animal's eye, each with the apparent ability to constrict). Your veterinarian will perform a thorough physical and ophthalmological exam on your cat.