The retina is a thin membranous lining at the back of the eye that transmits information to the brain based on the amount of light that enters the eye through the iris. A healthy retina is necessary for good vision but can be subject to a number of diseases that require treatment and surgery.
Some diseases of the retina include both wet and dry age-related macular degeneration, diabetic retinopathy, diabetic macular edema, proliferative diabetic retinopathy, macular holes and also retinal detachment.
These diseases are often a result of ageing, diabetes and even injury to the eyes, and may require retinal surgery as treatment.
As mentioned above, there are many diseases that can affect the retina and each one can be caused by different factors in a patient’s life.
Age-related Macular Degeneration
Age-related macular degeneration, or dry AMD, is the natural degeneration of eyesight in older adults caused by the build-up of fatty protein deposits called drusen under the retina. The drusen can damage the retina and light-sensitive cells in the eye, causing blurry vision.
Wet AMD occurs when abnormal blood vessels start to grow under the central area of the retina. These blood vessels often leak blood and fluid, damaging or killing light-sensitive cells. Loss of vision occurs quickly in this case.
Although wet AMD can lead to blindness, age-related macular degeneration can be treated and managed with the help of ophthalmologists.
Diabetic Retinopathy is a complication of diabetes that causes damage to the blood vessels of the retina, resulting in loss of vision. The longer someone has diabetes, especially if it’s unmanaged, the more likely the possibility that a person will develop diabetic retinopathy. Diabetic macular edema and proliferative diabetic retinopathy are forms of diabetic retinopathy.
Diabetic Macular Edema
Diabetic macular edema is the swelling of the central part of the retina, also known as the macula. This part of the eye is used for sharp, straight-ahead vision and nourished by blood vessels. In diabetic patients, these blood vessels weaken and cause the retina to become thick and swollen, damaging vision.
Proliferative Diabetic Retinopathy
Proliferative diabetic retinopathy is a form of diabetic retinopathy caused by damaged blood vessels and poor circulation in the retina. Vision is lost when retina tissue dies as a result of this inadequate blood supply.
Poor circulation may also lead to the development of new blood vessels and scar tissue on the retina. If these vessels bleed into the middle cavity of the eye, vision loss can occur. Scar tissue formation can also pull on the retina, detaching it from the back of the eye, resulting in visual loss.
A macular hole is a small, thick retinal defect in the macula. A macular hole or pucker, also known as epiretinal membrane, refers to semitransparent scar tissue on the surface of the retina that can cause distortion and swelling of the retina.
Although a direct cause for macular holes is unknown, the disease can be caused by injury and other eye-related problems.
A retinal detachment is a medical emergency and occurs when the retina is lifted or pulled from its normal position in the eye. It may begin with a small tear or break that leads to a full detachment. This is usually caused by injury to the eye and is common in people over the age of 40. It also affects men more than women.
At Somerset Eye, an ophthalmologist will dilate a patient’s eyes during a comprehensive examination to identify any retinal disease. Eye drops are placed in the eyes to dilate the pupils before the eye specialist examines the retina with magnifying lenses. The dilation fades after several hours.
Depending on their severity, retinal diseases like age-related macular degeneration and diabetic retinopathy (including diabetic macular edema and proliferative diabetic retinopathy) can be treated medically or surgically.
In some cases, ophthalmologists will inject drugs into the eye to block leakages from existing abnormal blood vessels and stop new growth. Laser eye surgery can also be performed under local anaesthetic to damage abnormal blood vessels as well. If the degeneration or diabetic retinopathy is too severe, however, eye specialists at Somerset Eye may surgically remove blood and scar tissue on the eye.
When it comes to macular holes and retinal detachment, surgery is required. At Somerset Eye, eye specialists will perform a vitrectomy to treat macular holes. During this procedure, the vitreous gel in the eye is removed and replaced with a bubble of gas and air. Over the course of a few days to weeks the bubble will help the macular hole close. Patients may be required to maintain a face-down position for a few days after surgery to help the gas bubble exert pressure on the hole and help it close. The gas bubble will gradually dissolve and leave the eye over a few weeks.
Retinal detachment is an emergency and can be repaired with eye surgery or laser treatment depending on its severity. At Somerset Eye, ophthalmologists may perform freeze treatment, a form of laser eye surgery, to fix small tears in the eye. During the operation, an eye specialist will use a freezing probe to repair damage on the retina. In more severe cases, retinal detachment will require surgery to reset the eye.