Some patients also find it difficult going from a brightly lit environment such as outside on a sunny day to a poorly lit room in the house as it takes longer to adjust to the new level of lighting. It can also result in difficulty seeing if you wake up in the night to go to the toilet as the macula again takes time to adjust when the light is switched on. In early macular degeneration these cells take longer to “get going” and often need more light to function well and this is the reason for developing these symptoms. When you wake up in the morning and the lids open, the retina has to start work straight away with the rods and cones converting the light into electricity.
#Yellow spots before your eyes Patch#
Patients with mild macular degeneration are often aware that vision is better in good light and that on waking from sleep in the morning there is often a blurred patch in the centre of the vision that gradually fades. Symptoms usually develop gradually with dry macular degeneration but are of sudden onset with wet macular degeneration (see below). The healthy peripheral retina is also the reason why magnifiers are of benefit to patients with this condition as the image is enlarged onto this. This enables patients to see to navigate around and remain independent. The side or peripheral retina is unaffected and therefore the side vision or peripheral vision is maintained. It only involves the central retina (macula) which is an important but small part of the retina. It must be emphasised however that it is not a blinding condition and does not lead to complete loss of vision. Patients complain of a blurred patch in the centre of the vision or sometimes distortion of vision (straight lines looking kinked or uneven). Macular degeneration is the most common cause of loss of vision in patients over the age of 55 in the Western World. What are the symptoms of macular degeneration? Smoking is a very bad thing for the body for a large number of reasons and this also includes increasing your risk of developing severe macular degeneration.
Unfortunately the light damage to the DNA cannot be repaired as the retina (and macula) are part of the central nervous system (part of the brain) and they can only scar and not regenerate or repair easily.Ī small number of patients have inherited genes that make them more prone to developing macular degeneration and may develop it at a younger age. Anti-oxidant vitamins (such as vitamin C and E) help “mop up” the damaging “free radicals” and this is how vitamin supplements are thought to be beneficial in some patients with macular degeneration. Lutein is a pigment that you get from your diet and is present at the macula and helps prevent the high energy blue light from reaching the rods and cones. The eye has some defence against this ageing process. The RPE recycling also becomes less efficient with the passage of time and “waste products” accumulate within the retina called “drusen” The high energy light can produce particles called “free radicals” which damage the cells and the high energy light can also damage the genetic material in the cells called “DNA” that controls the function of the cell.
The light that focuses on the macula and in particular the blue end of the spectrum has high energy and can damage the cells in a variety of ways.
#Yellow spots before your eyes full#
The rods and cones need to recycle material in order to function in an efficient manner and the RPE assists in this recycling.Īs the macular is working “at full stretch” it is not surprising that with the passage of time it is more prone to the ageing process than other tissues in the body. They work so hard that they need both a very good blood supply called the choroid (to give oxygen and sugar to the cells) and a layer of cells beside them called the Retinal pigment epithelium (RPE) to help them function. The cells at the macular that are responsible for changing the light into electricity are called photoreceptors (rods and cones). It is responsible for converting the focused image of light striking the retina into electrical impulses that are sent to the brain to give us sight.
It is the most sophisticated piece of tissue in the body and works “flat out” from the moment you open your eyes in the morning to the moment you go to sleep.
It is responsible for detailed vision (reading, writing, recognising faces) and for colour vision. The macula is the name given to the centre of the retina (photographic film at the back of the eye).
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