A cyst is a thin-walled hollow organ or cavity containing liquid secretion. An iridociliary cyst is a small hollow structure attached to the iris (colored part of the eye) or floating freely in the anterior of the chamber of the eye. Also known as iris cyst or uveal cyst, they are more or less densly pigmented which gives them a brown to yellowish color. The cysts may vary in size, shape and numbers. They are most commonly seen as secondary to inflammation in the eye, especially with canine glaucoma. Most cysts remain undetected, unless they push on the iris or get relatively large.
Although they are benign in nature and do not require any treatment, if they become too large, they may obscure the vision or interfer with function of the eye. Less often, an iris cyst may prevent the pupil from constricting properly, or may rub against the cornea and cause cloudiness.
There are certain breeds of dogs that are thought to be predisposed to iris cysts. These breeds include Golden Retrievers, Labrador Retrievers, and Boston Terriers. In Golden Retrievers, uveal cysts are commonly associated with anterior uveitis (inflammation inside the eye) bearing the risk to develop glaucoma, corneal edema and ulceration.
There are no symptoms associated with iris cysts since they cause no harm to the eye. Most commonly, they are accidental findings. The cysts are problematic when they become large enough or numerous enough to cause problems in the vision. Glaucoma can be a complication associated with iridociliary cysts.