This is a muscular body that encircles the inside of the eye behind the iris.
Like the iris it has a circular sphincter which causes the ciliary body to constrict centrally, like the pupil of the iris constricts in bright light.
The ciliary body constricts with the pupil during reading or looking at near objects, this allows the lens to change shape and focus. There is also a ciliary body muscle to counter this.
The continuous formation of internal ‘Aqueous’ fluid, by the ciliary body epithelium, keeps the eye ball inflated. See Aqueous flow.
This information site has been provided by varied UK and US eye doctors for patients with eye problems.
Once your eye doctor has made a diagnosis or recommended an investigation or treatment, then you will be able to find further explanation on this site.
It is not a self diagnosis centre. It should not be relied upon without taking professional advice.