If you have noticed a white ring around your iris then there is no need to be alarmed. Arcus Senilis is a grey, white or sometimes blue arc visible above and below the outer part of your cornea which is the transparent covering over your eyeball. It will typically start as a small arc but it can eventually create a full ring around your iris.
What is it caused by?
The condition is far more common in older adults. The visible ring is due to fat deposits or lipids building up in the deep edge of the cornea over your lifetime. The condition is due to age rather than an underlying health issue. Rings in the eyes of patients over the age of 50 are not usually seen as a cause for concern but instead viewed as a natural sign of ageing. Blood vessels in the eye widen with age and this allows a more significant build-up of cholesterol and other fats. In patients under the age of 40, the condition is identified as Arcus Juvenilis and can suggest that you have high levels of fat in your blood.
The arc can usually be seen by the naked eye but it is best viewed under high magnification by an optometrist. The condition is asymptomatic, it should not be causing any type of pain or irritation nor disturbing your vision in any way. It may just be identified during a routine eye examination before you have even noticed it.
The white arc should not affect your vision and it does not normally require any treatment. However, if you are under the age of 40 and experiencing the condition then it would normally be recommended that you visit your GP as it could be a sign that you have an issue with heightened cholesterol.
Should I be concerned?
It is always wise to have any changes in the appearance of your eyes checked by a qualified professional. The appearance of a white ring can be unsettling but if you receive a diagnosis of Arcus Senilis then there is no need to be overly concerned. Some people are under the misapprehension that it is a sign of cataracts forming but this is untrue. If you are of a younger age with the condition, then your GP should be notified and can follow up with you to advise of any appropriate lifestyle changes or medication that may be required.