Almost every person has experienced or will experience shadows in their vision, referred to as “floaters”, during their lifetime. Many people have only one floater but often people suffer from multiple floaters. In most cases, this is a minor and temporary inconvenience, but for some it can become a permanent and disabling condition. If you suffer from eye floaters, then you are already familiar with the frustrating visual disturbance caused by these cobweb and cloud-like shadows.
Types of Floaters
Floaters come in many shapes and sizes. Some are present as grey or black dots. Sometimes the appear as cobwebs or squiggly lines. Commonly many people complain of seeing rings of different forms which may be twisted or curved.
Causes of Floaters
The vitreous humor is the clear, jelly-like substance in the main chamber of the eye, located between the lens and the retina. At a young age, the vitreous is perfectly transparent. Over time as the eye ages, the vitreous humor can degenerate, loosing its form and liquefying. Without the stable vitreous humor, the collagen fibers collapse and bind together to form clumps and knots. These fibers cast shadows on the eye’s retina. It is these shadows that are commonly referred to as “eye floaters”. Floaters are little “cobwebs” or specks that float in your field of vision. They are small, dark, shadowy shapes that can look like spots, threadlike strands, or squiggly lines. Floaters are visible only because they do not remain fixed in location. If floaters were still instead of floating around, for example, your brain would automatically ignore them and you would never consciously see them. The brain often does this with things positioned both in and outside of the eye. For example, you do not perceive the blood vessels in your eye, which are fixed in location close to the retina, because your brain ignores them. Whilst a floater remains dormant in your eye, it is suspended in the vitreous humor and will therefore drift in line with your eye movement – and hence it often appears to be “moving”. You can see floaters better when looking at a bright blue sky because your pupils contract to a very small size, which in turn makes floaters more pronounced. Typically, a floater will not significantly change its shape or size during a patient’s lifetime. Floaters are more likely to develop as we age and are more common in people who are very nearsighted, have diabetes, or who have had a cataract operation.
What is Degenerative Vitreous Syndrome? The vitreous humor is the clear, jelly-like substance in the main chamber of the eye, located between the lens and the retina. At a young age, the vitreous is perfectly transparent. Over time as the eye ages, this vitreous humor can degenerate, losing its form and liquefying. Without the stable vitreous humor, the collagen fibers collapse and bind together to form clumps and knots. It is these fibers, which cast shadows on the retina and appear as spots, strings, or cobwebs that are commonly referred to as “eye floaters.”
Posterior Vitreous Detachment (PVD)
Posterior Vitreous Detachment (PVD) occurs when the vitreous humor peels away from the retina entirely. PVD generally occurs as the eye ages and is often associated with a sudden increase in the number of floaters. Whilst floaters are considered benign and do not generally affect visual acuity, they can negatively affect quality of vision.
When a person sees new floaters, it is usually a sign of an Acute PVD. The appearance of new floaters is often accompanied by flashing lights (or flashes) in the eye - this is due to the vitreous gel pulling on the retina (the nerve layer of the eye) which triggers the sensation of seeing flashes of light, usually like a lightning flash or a flickering fluorescent light. A person who sees repeated flashing lights in their vision should seek urgent review by a medical eye specialist. This is because sometimes, the vitreous pulling on the retina can cause it to tear, leading to bleeding and/or a Retinal Detachment which is an ocular emergency - an eye condition that if not treated urgently can lead to blindness. The appearance of large floaters - like curtains or veils in the vision - could indicate bleeding from a retinal tear or a retinal detachment.
An acute PVD needs to be urgently assessed by an ophthalmologist or a medically trained eye specialist, who can fully examine the retina, locate any retinal tears and treat them with laser to prevent a retinal detachment.
A posterior vitreous detachment or PVD occurs in most people. Generally, it happens in mid-life but can happen earlier in life in short-sighted or myopic people, or if there has been trauma or disease in the eye. For the majority of people, flashes are not seen, or people are not aware of them and, if they are, the flashes settle without causing any problems. What is left, once flashes stop, are long-standing floaters of different shapes, as described above. If they float into the centre of your vision, they can interfere with reading, watching television and they can be distracting while performing other activities, such as driving.
Most people with floaters do not see them everyday. They occur randomly and it is unpredictable when they appear. What is certain though, is floaters never go away on their own. In the past, and even now, many eye care practitioners advise their patients to "put up" with these symptoms of floaters and, while it is true that you can "get used to them", these floaters can be quite troublesome as they are permanent. They sometimes can interfere with reading, watching TV or, worse still, driving.
Treatment of Floaters - Laser Floater Treatment
What is LFT? Also known as laser floater treatment or laser vitreolysis, LFT is a non-invasive procedure that can eliminate the visual disturbance caused by eye floaters. The goal of LFT is to achieve a “functional improvement”. That is, to allow you to return to “normal” day-to-day activities without the hindrance of floaters.
How does LFT work? LFT involves the application of nanosecond pulses of laser light to evaporate the vitreous opacities and to sever the vitreous strands. During this process, the floater's collagen and hyaluronin molecules are converted into a gas. The end result is that the floater is removed and/or reduced in size.
What happens during the procedure? LFT is performed as an outpatient procedure; you do not have to stay overnight in a hospital. Immediately prior to treatment, your ophthalmologist will administer eye drops to provide mild anesthesia. A contact lens will then be placed on your eye, with the laser light delivered through a specially designed microscope. During treatment, you will likely observe small, dark specks/shadows – signaling that the floaters are being evaporated into small gas bubbles. These gas bubbles quickly dissolve and resorb into the vitreous. Once the treatment is complete, your ophthalmologist may treat your eyes with anti-inflammatory drops. Each treatment session typically takes 20-60 minutes to perform and most patients will need to undergo two treatment sessions, sometimes three, in order to achieve a satisfactory result.
What can I expect after treatment? You may observe small, dark specks in your lower field of vision immediately following treatment, but these small gas bubbles will quickly dissolve. It is also important to note that some patients may experience mild discomfort, redness or temporarily blurred vision directly following treatment.
Complications and side effects Reported side effects and complications associated with LFT are rare. Side effects may include cataract and intraocular pressure (IOP) spike.