Uvea is different from the uvula. Uvula refers to the small tissue that dangles in the back of your mouth while uvea is the middle layer of the eyeball that is pigmented and has three parts.
The three segments of the uvea:
Iris is the colored part of our eye which is made of connective tissue and muscle. The amount of pigment in the iris determines the color of our eyes.
The ciliary body is not visible because it is located behind the sclera or the white part of the eye. The ciliary body surrounds the iris.
The choroid is located at the posterior part of the uvea. It is found between the outer sclera and the retina.
Function of Each Component
Iris, ciliary body, and choroid have their specific function:
Iris gives your eye color and controls the size of your pupil. It can be seen when there is full sunlight and the iris constricts the pupil and dilates the pupil in a dark room.
The ciliary body acts as a holder to the lens of the eye. It has tiny ligaments called ciliary zonules that allow the lens to maintain its place behind the pupil.
Choroid nourishes the retina with the tiny blood vessels that it contains.
Problems concerning uvea can be genetic, age-related, or associated with health problems.
These are the following problems with uvea:
Uveitis is a very common condition wherein inflammation occurs in the uvea. Iritis is the term if it occurs in the iris. Anterior uveitis or iridocyclitis is when the inflammation affects both the iris and ciliary body. Painful red eyes, light-sensitive, and decreased visual acuity are the most common symptoms.
Synechia occurs when there is a trauma in the eye or iritis. It can lead to certain types of glaucoma which makes it dangerous.
Iris coloboma is a congenital disorder. When you have this, you get a “cat-eye” appearance because a portion of normal iris tissue is missing. Blurred vision, decreased visual acuity, and double vision can occur if you have iris coloboma. Prosthetic contact lenses are used to address this problem to enhance the appearance of the eye.
Uveal melanoma is a common type of cancer in the eye. The growth of cancer occurs within the iris, ciliary body, or choroid.
A choroidal nevus is a pigmented freckle in the choroid that is benign.
Choroideremia is hereditary and degeneration of choroid occurs progressively. It is characterized by night blindness and decreased visual field. This type of condition primarily affects men.