Posterior vitreous detachments and retinal detachments Floaters caused in this way tend to be few in number and of a linear form. The collagen breaks down into fibrils, which ultimately are the floaters that plague the patient. Depolymerization of this network makes the hyaluronic acid release its trapped water, thereby liquefying the gel. The solid portion consists of a network of collagen and hyaluronic acid, with the latter retaining water molecules. The most common cause of floaters is shrinkage of the vitreous humour: this gel-like substance consists of 99% water and 1% solid elements. Basically, any way by which material enters the vitreous humour is a cause for floaters. There are various causes for the appearance of floaters, of which the most common are described here. Some sufferers have noted a decrease in ability to concentrate while reading, watching television, walking outdoors, and driving, especially when tired. For people with severe floaters it is nearly impossible to completely ignore the large masses that constantly stay within almost direct view. Most sufferers are able to, with time, learn to ignore their floaters. Many times they trick the sufferer into thinking they see something out of the corner of their eye that really is not there. In some cases, floaters are congenital.įloaters have been known to catch and refract light in ways that somewhat blur vision temporarily until the floater moves to a different area.

They are also common after cataract operations or after trauma. It is not, however, only elderly people who suffer from floaters they can certainly become a problem to younger people, especially if they are myopic. Floaters can even be seen when the eyes are closed on especially bright days, when sufficient light penetrates the eyelids to cast the shadows. The shapes are shadows projected onto the retina by tiny structures of protein or other cell debris discarded over the years and trapped in the vitreous humour. However, floaters are more than a nuisance and a distraction to those with severe cases, especially if the spots seem to constantly drift through the field of vision. Despite the name 'floaters', many of these specks have a tendency to sink toward the bottom of the eyeball, in whichever way the eyeball is oriented the supine position (looking up or lying back) tends to concentrate them near the fovea, which is the center of gaze, while the textureless and evenly lit sky forms an ideal background against which to view them.įloaters are not uncommon, and do not cause problems for most people. This does not occur with floaters and they remain visible.įloaters are particularly noticeable when looking at a blank surface or an open monochromal space, such as blue sky. Although the blood vessels of the eye also obstruct light, they are invisible under normal circumstances because they are fixed in location relative to the retina, and the brain 'tunes out' stabilized images due to neural adaptation. Floaters are, in fact, visible only because they do not remain perfectly fixed within the eye. However, attempting to shift one's gaze toward them can be difficult since floaters follow the motion of the eye, remaining to the side of the direction of gaze. When they are first noticed, the natural reaction is to attempt to look directly at them. Thus, they generally follow the rapid motions of the eye, while drifting slowly within the fluid. 2.2 Posterior vitreous detachments and retinal detachmentsįloaters are suspended in the vitreous humour, the thick fluid or gel that fills the eye.Latin-derived Muscae volitantes (meaning 'flying flies'), or French-derived mouches volantes, are a specific type of floater consisting of small spots whose presence is normal and attributed to minute remnants of embryonic structures in the vitreous humour. They may appear as spots, threads, or fragments of cobwebs, which float slowly before one's eyes. When observed subjectively, floaters are entoptic phenomena characterized by shadow-like shapes that appear singly or together with several others in one's field of vision. The perception of floaters is known as myodesopsia, or less commonly as myiodeopsia, myiodesopsia, or myodeopsia. They may be of embryonic origin or acquired due to degenerative changes of the vitreous humour or retina. (April 2007)įloaters Classification & external resources ICD-10įloaters are deposits of various size, shape, consistency, refractive index, and motility within the eye's normally transparent vitreous humour. Using inline citations helps guard against copyright violations and factual inaccuracies. This article or section is missing citations or needs footnotes.

Causes entoptic phenomena