PVD, Retinal tears and detachment
Retinal detachment describes an emergency situation in which a critical layer of tissue (the retina) at the back of the eye pulls away from the layer of blood vessels that provides it with oxygen and nourishment. Retinal detachment leaves the retinal cells lacking oxygen. The longer retinal detachment goes untreated, the greater your risk of permanent vision loss in the affected eye. Fortunately, retinal detachment often has symptoms that are clear warning signs. Early diagnosis and treatment of retinal detachment can save your vision. If you suspect you may have a retinal detachment, contact an eye specialist (ophthalmologist) as soon as warning signs appear.
Retinal detachment itself is painless, but retinal detachment warning signs and symptoms almost always appear before it occurs or has advanced. Retinal detachment symptoms may include:
- The sudden appearance of many floaters — small bits of debris in your field of vision that look like spots, hairs or strings and seem to float before your eyes
- Sudden flashes of light in the affected eye
- A shadow or curtain over a portion of your visual field that develops as the detachment progresses
Retinal detachment can occur as a result of:
- Shrinkage or contraction of the vitreous (VIT-ree-us) — the gel-like material that fills the inside of your eye. This can create tugging on the retina and a retinal tear, leading to a retinal detachment.
- Advanced diabetes
- An inflammatory eye disorder How retinal detachment occurs Retinal detachment can occur when the gel-like material (vitreous) leaks through a retinal hole or tear and collects underneath the retina.
Reasons for holes or tears include:
- Aging or retinal disorders can cause the retina to thin. Retinal detachment due to a tear in the retina typically develops when there is a sudden collapse of the vitreous, causing tugging on the retina with enough force to create a tear. Fluid inside the vitreous then finds its way through the tear and collects under the retina, peeling it away from the underlying tissues. These tissues contain a layer of blood vessels called the choroid (KOR-oid). The areas where the retina is detached lose this blood supply and stop working, so you lose vision.
In certain inflammatory conditions or other disorders, fluid also can accumulate beneath the retina without a tear or break.
- Aging-related retinal tears that lead to retinal detachment As you age, your vitreous may change in consistency and shrink or become more liquid. Eventually, the vitreous may separate from the surface of the retina — a common condition called posterior vitreous detachment (PVD). It’s also called vitreous collapse. As the vitreous separates or peels off the retina, it may tug on the retina with enough force to create a retinal tear. Left untreated, fluid from the vitreous cavity can pass through the tear into the space behind the retina, causing the retina to become detached. PVD can cause visual symptoms. You may see flashes of sparkling lights (photopsia) when your eyes are closed or when you’re in a darkened room. New or different floaters may appear in your field of vision.
The following factors increase your risk of retinal detachment:
- Aging — retinal detachment is more common in people older than age 40
- Previous retinal detachment in one eye
- A family history of retinal detachment
- Extreme nearsightedness (myopia)
- Previous eye surgery, such as cataract removal especially if it was a complicated surgery
- Previous severe eye injury or trauma
- Previous other eye disease or disorder
Preparing for your appointment
See an ophthalmologist if you have any sudden changes in your vision. If he or she suspects or concludes you have a retinal tear or retinal detachment, you will likely be urgently referred to an ophthalmologist who is also a retinal specialist. Because there’s often a lot of ground to cover at your appointment, it’s a good idea to be well prepared. Here’s some information to help you get ready and what to expect from your doctor:
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there’s anything you need to do in advance
- Write down any symptoms you’re experiencing. Include even those that may seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information. Include any major stresses or recent life changes
- Make a list of all your medications. Also include any vitamins or supplements you’re taking
- Take along a family member or friend. Sometimes it can be difficult to take in all the information provided during an appointment. Someone who accompanies you may remember something you missed or forgot.
- Write down all your questions. Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. List your questions from most important to least important in case time runs out.
For retinal detachment, some basic questions to ask your doctor include:
- What is likely causing my symptoms or condition?
- What are other possible causes for my symptoms or condition?
- What kinds of tests do I need?
- Is my vision loss likely temporary or ongoing?
- What is the best course of action?
- What are the alternatives to the first approach that you’re suggesting?
- I have some other health conditions. How can I best manage them together?
- Are there any restrictions I need to follow
- Should I see another specialist?
- Are there any brochures or other printed material I can take with me? What websites do you recommend?
- What will determine whether I should plan for a follow-up visit?
- If I need surgery, how long will recovery take?
- Will I be able to travel after surgery? Will it be safe to travel by plane? In addition to the questions that you’ve prepared to ask your doctor, don’t hesitate to ask additional questions during your appointment.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may allow more time to cover points you want to address. Your doctor may ask:
- When did you first begin experiencing symptoms?
- Have your symptoms been continuous or occasional?
- How severe are your symptoms?
- Have you had any symptoms in your other eye?
- Have you ever had an eye injury?
- Have you ever experienced eye inflammation?
- Have you ever had eye surgery?
- Do you have any other medical conditions, such as diabetes?
- Have any of your family members ever had a retinal detachment?
Tests and diagnosis
Our staff may use the following tests, instruments and procedures to diagnose retinal detachment:
- Ophthalmoscope. The doctor may use an instrument with a bright light and a special lens to examine the inside of your eyes. The ophthalmoscope provides a highly detailed 3-D view, allowing the doctor to see any retinal holes, tears or detachments.
- Ultrasonography. This test uses sound waves to create a picture on a video monitor. The sound waves travel through your eye and bounce off your retina and other structures within the eye to create the image.
- Retina OCT
- Fundus photography
Surgery is almost always used to repair a retinal tear, hole or detachment. Your ophthalmologist can tell you about the various risks and benefits of your treatment options. Together you can determine what treatment is best for you.
When a retinal tear or hole hasn’t yet progressed to detachment, your eye surgeon may suggest an outpatient procedure, which can usually prevent retinal detachment and preserve almost all of your vision.
•Laser surgery (photocoagulation). The surgeon directs a laser beam at the retinal tear. The laser makes burns around the tear, creating scarring that usually “welds” the retina to underlying tissue.
•Freezing. In this process, called cryopexy (KRY-o-pek-see), the surgeon applies a freezing probe to the outer surface of the eye directly over the retinal defect and freezes the area around the hole, resulting in a scar that helps secure the retina to the eye wall. After your procedure, you likely will be advised to refrain from vigorous activity for the next two weeks or so to allow time for the bonds created by your procedure to strengthen.
YAG laser obliteration of SIGNIFICANT vitreous floaters. Because laser treatment of floaters is almost unknown, these floater patients are told to “learn to live with it” and that vitrectomy is the only treatment. But vitrectomy is rarely recommended because of the high risk of cataract formation and a 1% to 3% risk of retinal detachment. The result is that persistent symptomatic floater patients rarely receive treatment. For more details, visit Laser for Persistent Floaters
If your retina has detached, doctors will also use surgical procedures to repair it. These procedures may be done along with photocoagulation or cryopexy. The specifics of your retinal detachment will determine which approach your surgeon recommends. Sometimes people need a second surgery for successful treatment.
•Injecting air or gas into your eye. In this procedure, called pneumatic retinopexy (RET-ih-no-pek-see), your doctor injects a bubble of air or gas into the vitreous. When the bubble is successfully placed to float against the retinal tear and the area surrounding the tear, it seals the tear. This stops further flow of fluid into the space behind the retina. Fluid that had collected under the retina is absorbed by itself, and the retina can then reattach itself to the back wall of your eye. You may need to hold your head in a certain position for up to several days to keep the bubble in place. The bubble eventually will also be reabsorbed on its own.
•Indenting the surface of your eye. This procedure, called scleral (SKLEER-ul) buckling, involves the doctor sewing (suturing) a piece of silicone rubber or sponge to the white of your eye (sclera) over the affected area. The silicone material indents the wall of the eye and relieves some of the force caused by the vitreous tugging on the retina. If you have several tears or holes or an extensive detachment, your surgeon may create a scleral buckle that circles your entire eye like a belt. The buckle usually remains in place for the rest of your life.
•Draining and replacing the fluid in the eye. In this procedure, called vitrectomy (vih-TREK-tuh-me), the doctor removes the vitreous along with any tissue that is tugging on the retina. Air, gas or liquids are then injected into the vitreous space to reattach the retina. Eventually the air, gas or liquid will be absorbed and the vitreous space will refill with body fluid. However, if the retinal detachment repair uses a silicone oil, the oil is often surgically removed months later. A vitrectomy is often combined with a scleral buckling procedure.
Coping and support
Retinal detachment may cause you to lose vision in the portion of your field of vision that corresponds to the detached part of the retina. Depending on your degree of vision loss, your lifestyle might change significantly. Yet there are many things you can do to cope with impaired vision:
Check into transportation. Investigate vans and shuttles, volunteer driving networks, or ride shares available in your area for people with impaired vision.
Get special glasses. Optimize the vision you have with glasses that are specifically prescribed for the effects of retinal detachment. You may also be prescribed other visual devices.
Get help from technology. Digital talking books and computer screen readers can help with reading, and other new technology continues to advance.
Brighten your home. Have proper light in your home for reading and other activities.
Make your home safer. Eliminate throw rugs and place colored tape on the edges of steps. Consider installing motion-activated lights.
Enlist the help of others. Tell friends and family members about your vision problems so they can help you.
Talk to others with impaired vision. Take advantage of online networks, support groups and resources for people with impaired vision.
There is no way to prevent retinal detachment. However, being aware of the following typical warning signs of a detached retina could help save your vision:
- Sudden increase in floaters
- Bright flashes of light
- A shadow or curtain that seems to advance across your visual field If you notice any of these signs — particularly if you’re older than age 40, you or a family member has had a detached retina, or you’re extremely nearsighted — you should seek immediate medical attention.
Age-Related Macular Degeneration
(Aging spots at the center of the vision)
Cover each eye one at a time and stare at the black dot in the center. If the straight lines appear broken, crooked, wavy, bent, or distorted, you may have AMD. This test is hardly sufficient to rule out the possibility that one has developed AMD, as many people with AMD may see no abnormalities on an Amsler grid (see image below). The best way to detect AMD is an examination with a retina specialist. The following are some typical methods he/she will use to check for AMD.
Dilated Fundus Exam
The retina specialist uses eye drops to dilate, or widen, the pupil to examine the retina. Regular dilated eye exams are important, especially when you’re at higher risk for AMD. If you are over the age of 50, an exam every one to two years is a good idea in order to look for signs of AMD before any vision loss has occurred.
This is the eye chart used to determine how well people see at distances
Ocular coherence tomography
This scan measures the macula thickness and detects any fluid buildup behind the retina, as well as other changes that happen with AMD.-
This test would accurately document the changes that happen with age and the progression of the AMD. Minor changes that could not be discovered by regular fundus exam can be seen on serial photos.
Intravitreal Medication injections
In some cases, medication may be used to help treat diabetic retinopathy. Sometimes a steroid medication is used. In other cases, you may be given an anti-VEGF medication. This medication works by blocking a substance known as vascular endothelial growth factor, or VEGF. This substance contributes to abnormal blood vessel growth in the eye which can affect your vision. An anti-VEGF drug can help reduce the growth of these abnormal blood vessels.After your pupil is dilated and your eye is numbed with anesthesia, the medication is injected into the vitreous, or jelly-like substance in the back chamber of the eye. The medication reduces the swelling, leakage, and growth of unwanted blood vessel growth in the retina, and may improve how well you see.Medication treatments may be given once or as a series of injections at regular intervals, usually around every four to six weeks or as determined by your doctor.
Treatment can’t reverse dry macular degeneration. But this doesn’t mean you’ll eventually lose all of your sight. Dry macular degeneration usually progresses slowly, and many people with the condition can live relatively normal, productive lives, especially if only one eye is affected.Increased vitamin intake
Taking a high-dose formulation of antioxidant vitamins and zinc may reduce the progression of dry macular degeneration to vision loss, according to research by the National Eye Institute (NEI). In its research, the NEI used a formulation that included:
- 500 milligrams (mg) of vitamin C
- 400 international units (IU) of vitamin E
- 15 mg of beta carotene (often as vitamin A — up to 25,000 IU)
- 80 mg of zinc (as zinc oxide)
- 2 mg of copper (as cupric oxide)
Studies found this specific combination of vitamins can’t cure severe vision loss, but it may reduce the risk of vision loss in people with intermediate macular degeneration. If you have advanced stage macular degeneration in one eye, this combination of vitamins may reduce the risk that you’ll develop vision loss in your other eye. But for people with early-stage dry macular degeneration, there’s no evidence that these vitamins provide a benefit. Some vitamin supplements may have complications and risks. Tell your doctor if you smoke or have smoked in the past, because beta carotene supplements have been associated with a higher risk of lung cancer in smokers. Beta carotene also may increase the risk of coronary artery disease. Also, high doses of vitamin E may increase the risk of heart failure and other complications.Your doctor may recommend lifestyle changes to include more of the fruits and vegetables that contain these vitamins into your diet, along with other foods that contain nutrients believed to contribute to eye health. Some people may prefer to make lifestyle changes rather than take supplements. Others may wish to combine supplements with lifestyle changes.Surgery to implant a telescopic lens in one eye
For selected people with advanced macular degeneration in both eyes, one option to improve vision may be surgery to implant a telescopic lens in one eye. The telescopic lens, which looks like a tiny plastic tube, is equipped with lenses that magnify your field of vision. The telescopic lens implant may improve both distance and close-up vision.
Anti-VEGF in AMD
VEGF in AMD
Diabetic retinopathy, the most common diabetic eye disease, occurs when blood vessels in the retina change. Sometimes these vessels swell and leak fluid or even close off completely. In other cases, abnormal new blood vessels grow on the surface of the retina.
Diabetic retinopathy usually affects both eyes. People who have diabetic retinopathy often don’t notice changes in their vision in the disease’s early stages. But as it progresses, diabetic retinopathy usually causes vision loss that in many cases cannot be reversed.There are two types of diabetic retinopathy: Background or nonproliferative diabetic retinopathy (NPDR) and Proliferative diabetic retinopathy (PDR)
Nonproliferative diabetic retinopathy (NPDR) is the earliest stage of diabetic retinopathy. With this condition, damaged blood vessels in the retina begin to leak extra fluid and small amounts of blood into the eye. Sometimes, deposits of cholesterol or other fats from the blood may leak into the retina.
NPDR can cause changes in the eye, including:
Microaneurysms: small bulges in blood vessels of the retina that often leak fluid.
Retinal hemorrhages: tiny spots of blood that leak into the retina.
Hard exudates: deposits of cholesterol or other fats from the blood that have leaked into the retina.
Macular edema: swelling or thickening of the macula caused by fluid leaking from the retina’s blood vessels. The macula doesn’t function properly when it is swollen. Macular edema is the most common cause of vision loss in diabetes.
Macular ischemia: small blood vessels (capillaries) close. Your vision blurs because the macula no longer receives enough blood to work properly.
Many people with diabetes have mild NPDR, which usually does not affect their vision. However, if their vision is affected, it is the result of macular edema and macular ischemia. Watch how macular edema and macular ischemia affect your eyes
Proliferative diabetic retinopathy (PDR) Proliferative diabetic retinopathy (PDR) mainly occurs when many of the blood vessels in the retina close, preventing enough blood flow. In an attempt to supply blood to the area where the original vessels closed, the retina responds by growing new blood vessels. This is called neovascularization. However, these new blood vessels are abnormal and do not supply the retina with proper blood flow. The new vessels are also often accompanied by scar tissue that may cause the retina to wrinkle or detach. PDR may cause more severe vision loss than NPDR because it can affect both central and peripheral vision. PDR affects vision in the following ways:Vitreous hemorrhage: delicate new blood vessels bleed into the vitreous — the gel in the center of the eye — preventing light rays from reaching the retina. If the vitreous hemorrhage is small, you may see a few new, dark floaters. A very large hemorrhage might block out all vision, allowing you to perceive only light and dark. Vitreous hemorrhage alone does not cause permanent vision loss. When the blood clears, your vision may return to its former level unless the macula has been damaged.Traction retinal detachment: scar tissue from neovascularization shrinks, causing the retina to wrinkle and pull from its normal position. Macular wrinkling can distort your vision. More severe vision loss can occur if the macula or large areas of the retina are detached.Neovascular glaucoma: if a number of retinal vessels are closed, neovascularization can occur in the iris (the colored part of the eye). In this condition, the new blood vessels may block the normal flow of fluid out of the eye. Pressure builds up in the eye, a particularly severe condition that causes damage to the optic nerve.
There are three types of diabetes.
- Type 1 diabetes: usually diagnosed in children and young adults and previously known as juvenile diabetes, where the body does not produce insulin.
- Type 2 diabetes: the most common form of diabetes. Either the body does not produce enough insulin or the body’s cells ignore the insulin.
- Gestational diabetes: blood sugar levels (glucose) become elevated during pregnancy in women who have never had diabetes before. Gestational diabetes starts when the mother’s body is not able to make and use all the insulin it needs during pregnancy.
People with any type of diabetes can develop hyperglycemia, which is an excess of blood sugar, or serum glucose. Although glucose is a vital source of energy for the body’s cells, a chronic elevation of serum glucose causes damage throughout the body, including the small blood vessels in the eyes.
Diabetic retinopathy risk factors
Several factors can influence the development and severity of diabetic retinopathy, including: Blood sugar levels Controlling your blood sugar is the key risk factor that you can affect. Lower blood sugar levels can delay the onset and slow the progression of diabetic retinopathy. Blood pressure A major clinical trial demonstrated that effectively controlling blood pressure reduces the risk of retinopathy progression and visual acuity deterioration. High blood pressure damages your blood vessels, raising the chances for eye problems. Target blood pressure for most people with diabetes is less than 130/80 mmHg. Duration of diabetes The risk of developing diabetic retinopathy or having your disease progress increases over time. After 15 years, 80 percent of Type 1 patients will have diabetic retinopathy. After 19 years, up to 84 percent of patients with Type 2 diabetes will have diabetic retinopathy. Blood lipid levels (cholesterol and triglycerides) Elevated blood lipid levels can lead to greater accumulation of exudates, protein deposits that leak into the retina. This condition is associated with a higher risk of moderate visual loss. Ethnicity While diabetic retinopathy can happen to anyone with diabetes, certain ethnic groups are at higher risk because they are more likely to have diabetes. These include African Americans, Latinos and Native Americans. Pregnancy Being pregnant can cause changes to your eyes. If you have diabetes and become pregnant, your risk for diabetic retinopathy increases. If you already have diabetic retinopathy, it may progress. However, some studies have suggested that with treatment these changes are reversed after you give birth and that there is no increase in long-term progression of the disease.
There are several parts to the exam: Visual acuity test This uses an eye chart to measure how well you can distinguish object details and shape at various distances. Perfect visual acuity is 20/20 or better. Legal blindness is defined as worse than or equal to 20/200 in both eyes. Slit-lamp exam A type of microscope is used to examine the front part of the eye, including the eyelids, conjunctiva, sclera, cornea, iris, anterior chamber, lens, and also parts of the retina and optic nerve. Dilated exam Drops are placed in your eyes to widen, or dilate, the pupil, enabling your Eye M.D. to examine more thoroughly the retina and optic nerve for signs of damage. It is important that your blood sugar be consistently controlled for several days when you see your eye doctor for a routine exam. If your blood sugar is uneven, causing a change in your eye’s focusing power, it will interfere with the measurements your doctor needs to make when prescribing new eyeglasses. Glasses that work well when your blood sugar is out of control will not work well when your blood sugar level is stable. Your Eye M.D. may find the following additional tests useful to help determine why vision is blurred, whether laser treatment should be started, and, if so, where to apply laser treatment. Fluorescein angiography Your doctor may order fluorescein angiography to further evaluate your retina or to guide laser treatment if it is necessary. This is a diagnostic procedure that uses a special camera to take a series of photographs of the retina after a small amount of yellow dye (fluorescein) is injected into a vein in your arm. The photographs of fluorescein dye traveling throughout the retinal vessels show:• Which blood vessels are leaking fluid;• How much fluid is leaking;• How many blood vessels are closed;• Whether neovascularization is beginning. Optical coherence tomography (OCT) OCT is a non-invasive scanning laser that provides high-resolution images of the retina, helping your Eye M.D. evaluate its thickness. OCT can provide information about the presence and severity of macular edema (swelling). Ultrasound If your ophthalmologist cannot see the retina because of vitreous hemorrhage, an ultrasound test may be done in the office. The ultrasound can “see” through the blood to determine if your retina has detached. If there is detachment near the macula, this often calls for prompt surgery. When your diabetic retinopathy screening is complete, your ophthalmologist will decide when you need to be treated or re-examined. If you have diabetes, you should see your ophthalmologist right away if you have any visual changes that affect only one eye, last more than a few days, and are not associated with a change in blood sugar. When to schedule an eye examination Diabetic retinopathy usually takes years to develop, which is why it is important to have regular eye exams. Because people with Type 2 diabetes may have been living with the disease for some time before they are diagnosed, it is important that they see an ophthalmologist (Eye M.D.) without delay. The American Academy of Ophthalmology recommends the following diabetic eye screening schedule for people with diabetes: Type 1 Diabetes: Within five years of being diagnosed and then yearly. Type 2 Diabetes: At the time of diabetes diagnosis and then yearly. During pregnancy: Pregnant women with diabetes should schedule an appointment with their ophthalmologist in the first trimester because retinopathy can progress quickly during pregnancy.
Laser surgery The laser is a very bright, finely focused light. It passes through the clear cornea, lens and vitreous without affecting them in any way. Laser surgery shrinks abnormal new vessels and reduces macular swelling. Treatment is often recommended for people with macular edema, proliferative diabetic retinopathy (PDR) and neovascular glaucoma. Laser surgery is usually performed in an office setting. For comfort during the procedure, an anesthetic eye drop is often all that is necessary, although an anesthetic injection is sometimes given next to the eye. The patient sits at an instrument called a slit-lamp microscope. A contact lens is temporarily placed on the eye in order to focus the laser light on the retina with pinpoint accuracy.
With laser surgery for macular edema, tiny laser burns are applied near the macula to reduce fluid leakage. The main goal of treatment is to prevent further loss of vision by reducing the swelling of the macula. It is uncommon for people who have blurred vision from macular edema to recover normal vision, although some may experience partial improvement.
Panretinal photocoagulation (PRP)
In PDR, the laser is applied to all parts of the retina except the macula (called PRP, or panretinal photocoagulation). This treatment causes abnormal new vessels to shrink and often prevents them from growing in the future. It also decreases the chance that vitreous bleeding or retinal distortion will occur. Panretinal laser has proven to be very effective for preventing severe vision loss from vitreous hemorrhage and traction retinal detachment. Multiple laser treatments over time may be necessary. Laser surgery does not cure diabetic retinopathy and does not always prevent further loss of vision.
Vitrectomy is a surgical procedure performed in a hospital or ambulatory surgery center operating room. It is often performed on an outpatient basis or with a short hospital stay. Either a local or general anesthetic may be used. During vitrectomy surgery, an operating microscope and small surgical instruments are used to remove blood and scar tissue that accompany abnormal vessels in the eye. Removing the vitreous hemorrhage allows light rays to focus on the retina again. Vitrectomy often prevents further vitreous hemorrhage by removing the abnormal vessels that caused the bleeding. Removal of the scar tissue helps the retina return to its normal location. Laser surgery may be performed during vitrectomy surgery. To help the retina heal in place, your ophthalmologist may place a gas or oil bubble in the vitreous space. You may be told to keep your head in certain positions while the bubble helps to heal the retina. It is important to follow your ophthalmologist’s instructions so your eye will heal properly.
Intravitreal Medication injections
In some cases, medication may be used to help treat diabetic retinopathy. Sometimes a steroid medication is used. In other cases, you may be given an anti-VEGF medication. This medication works by blocking a substance known as vascular endothelial growth factor, or VEGF. This substance contributes to abnormal blood vessel growth in the eye which can affect your vision. An anti-VEGF drug can help reduce the growth of these abnormal blood vessels. After your pupil is dilated and your eye is numbed with anesthesia, the medication is injected into the vitreous, or jelly-like substance in the back chamber of the eye. The medication reduces the swelling, leakage, and growth of unwanted blood vessel growth in the retina, and may improve how well you see. Medication treatments may be given once or as a series of injections at regular intervals, usually around every four to six weeks or as determined by your doctor.
A macular pucker (also called an epiretinal membrane) is a layer of scar tissue that grows on the surface of the retina, particularly the macula, which is the part of your eye responsible for detailed, central vision.
The macula is the small area at the center of the eye’s retina that allows you to see fine details clearly. The retina is a layer of light-sensing cells lining the back of your eye. As light rays enter your eye, the retina converts the rays into signals, which are sent through the optic nerve to your brain where they are recognized as images. Damage to your macula causes blurred central vision, making it difficult to perform tasks such as reading small print or threading a needle.
As we grow older, the thick vitreous gel in the middle of our eyes begins to shrink and pull away from the macula. As the vitreous pulls away, scar tissue may develop on the macula. Sometimes the scar tissue can warp and contract, causing the retina to wrinkle or become swollen or distorted.
The macula normally lies flat against the back of the eye. When wrinkles, creases or swelling affect the macula, vision can become blurry and distorted and you may even have a blind spot in your central vision.