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"What causes eye floaters?"

ZocdocAnswersWhat causes eye floaters?


Recently, I've been bothered by these small, clear shapes that swim across my field of vision. I've heard people call them 'floaters'. What is a floater, and what causes them?


The diagnosis and management of "floaters" should be done by specialists including internists, ophthalmologists, and others. Floaters are deposits of various size in the vitreous humour of the eye. The perception of floaters is known as myodesopsia. The vitreous humour is the clear gel that fills the inside of the eyeball. Floaters can be visible since they cast a shadow on the retina, which is in the back of the eyeball. Since the illusion occurs within the eye, the illusion is not optic but referred to as enoptic. The most common is cause is when the vitreous humor becomes too liquefied from shrinkage resulting in some collagen breakdown which then are perceived as floaters. Other serious, but less common, reasons to experience floaters is detachment of the vitreous body of the eye housing the vitreous humor from the retina called posterior vitreous detachment (typically a large ring may be seen) as well as detachment of the retina itself (sudden numerous red dots across the hold visual field may be seen; this requires immediate medical attention). Other causes include congenital artery malformations, retinal tears, swelling within certain parts of the eye, film related to tears, etc. The diagnosis and management can not be made without seeing the patient. It is therefore the strong recommendation to be evaluated by an ophthalmologist in person.

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