Diabetic Retinopathy- Diabetes can affect almost every tissue in the eye however the retina is most susceptible to damage from this chronic disease. Patients with non-proliferative diabetic retinopathy require monitoring and medical optimization to ensure their vision stays healthy. Some people with diabetes will develop swelling in their retina, called diabetic macular edema, which can blur their central vision. This swelling can be reduced with injections of drugs into the eye and/or laser treatments. Others can lose vision secondary to bleeding within the eye from abnormal blood vessels called proliferative diabetic retinopathy. In advanced stages, these blood vessels can cause retinal detachment which can lead to permanent vision loss. Patients with abnormal blood vessels require laser and or injections to halt their progression. In more advanced stages, surgery is required. Diabetic retinopathy is preventable and treatable if caught early so it is vitally important that patients with diabetes see an eye doctor for screening on a regular basis.
Age-related Macular Degeneration (AMD)- The macula is the central part of the retina and is responsible for fine central vision. As some people age, this area of the retina begins to degenerate. There is a dry form and a wet form. Dry AMD is usually milder and occurs earlier. It is associated with changes in the appearance of the macula that can only be detected by an eye doctor. Patients with dry AMD may have no symptoms or in advanced stages can lose central vision, called geographic atrophy. Studies have shown that a special combination of vitamins (the AREDS-2 formula) can prevent progression of moderate dry AMD to more advanced stages. Wet AMD refers to the stage when bleeding and swelling occurs underneath and within the retina. This leads to visual distortion, termed metamorphopsia. Patients with AMD should monitor their vision at home with an amsler grid to recognize changes early before permanent damage has occurred. Wet AMD is usually treated with injections of special medicines into the eye.
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Flashes and floaters, posterior vitreous detachment, retinal tears- Many of us notice small floating opacities in our vision when we look at a white background. Some notice them more than others. These floaters are a nuisance and usually a result of vitreous syneresis, or liquefaction of the vitreous gel. Our eye is filled with a thick gel called vitreous humour which is 99% water and firmly attached to the retina from birth. As we age, it becomes more liquid and begins to peel off the retina. This is a normal aging change and referred to as a posterior vitreous detachment. Signs of a posterior vitreous detachment include an increase in floaters as well as flashes of light. Flashes of light occur because the retina is being mechanically stimulated, similar to when you rub your eyes and see spots. The process is akin to peeling tape off of wallpaper; sometimes it comes off cleanly, other times the wallpaper tears. If your retina tears, you are at risk of developing a retinal detachment which can lead to permanent vision loss and is an emergency. Only an eye doctor can detect retinal tears. Its symptoms are no different than those of a posterior vitreous detachment. Anyone with an increase in floaters or new flashes of light should see an eye doctor to rule out a tear. If a tear is detected, it can be treated with laser to prevent retinal detachment. Some people, especially those who are near sighted, have weak areas in their retina that are at risk for becoming retinal tears. These lesions can also be prophylactically treated with laser. Floaters never go away, unless surgically removed, but will diminish over time as we neuroadapt to them.
Retinal Detachment- Retinal detachment is an emergency and occurs when the retina begins to peel off of the eye wall. Symptoms of a retinal detachment include an increase in flashes of light/floaters and an opaque curtain in the field of vision, which moves from the outside inwards. It can start at the top, bottom, or sides. Retinal detachments can sometimes be repaired in the office with a gas bubble and a laser but may also require more traditional surgery in the operating room. Sometimes, multiple surgeries are required including vitrectomy, scleral buckling, and the use of intraocular gases or oils. Retinal detachments usually occur secondary to a tear or hole in the retina which allows liquified vitreous to get underneath the retina causing it to separate from the back of the eye. If caught early, central vision can be preserved but if left too long retinal detachments can result in permanent vision loss. The main risk factors for retinal detachment are a positive family history, a history of trauma, and being very near-sighted. If you are concerned you may be developing a retinal detachment you should see your eye doctor urgently or go to your nearest emergency room.
Retinal vascular disease- This is a broad term and generally refers to retinal artery occlusions and retinal vein occlusions. Both problems are essentially strokes within the eye. They lead to sudden, painless vision loss. Arterial occlusions generally have a poor prognosis. Rarely, they can be reversed if treated within hours of the onset of symptoms. Vein occlusions can eventually lead to swelling of the retina, macular edema, which can be treated with laser or injections of special medicines into the eye. Occasionally both problems can lead to the growth of abnormal blood vessels and bleeding into the eye which may require laser and/or surgery. Patients with these problems need a comprehensive medical work-up to ensure there are no underlying predisposing conditions that require systemic treatment.
Choroidal vascular disease- The most common choroidal vascular disease that we see is called central serous chorioretinopathy (CSCR). This condition results in the accumulation of fluid underneath the retina. This condition is benign and usually improves on its own. The pathogenesis of CSCR is unknown but we do know that young men with type-A personalities are at the highest risk of developing it. Other risk factors include stress and the use of steroid containing medications. CSCR can recur and can happen in either eye. If it does not improve on its own there are different medications and laser therapies that can be performed. It is also important that patients with CSCR be monitored for the development of secondary problems that do require active treatment.
Vitreomacular traction (VMT)- The macula is the centre of the retina and is responsible for fine central vision. Sometimes the vitreous gel can pull on the macula and distort its shape. This can cause visual distortion and sometimes needs to be fixed with surgery.
Macular holes- The macula is the centre of the retina and isn responsible for fine central vision. When a hole develops in this region patients lose this central vision. A hole is not an emergency but should be fixed sooner than later. Most holes are fixed with surgery called pars plana vitrectomy/ membrane peeling. After this surgery a gas bubble is left inside the eye and patients must remain face down for a few days. After surgery the vision usually improves, but will never be as perfect as it was prior to the hole forming.
Epiretinal membranes- The macula is the centre of the retina and is responsible for fine central vision. Sometimes scar tissue can grow over the retina leading to retinal distortions. Most of the time, we do not know why this tissue forms but it can result after trauma, inflammation, retinal tears, and previous surgeries. This can only be treated with a surgery called pars plana vitrectomy/ membrane peeling. Vision usually improves but never completely.
Cataract and complications of cataract surgery- A cataract refers to a clouding of the lens, which works like a camera lens to focus light on the retina so we can see. Age-related cataract is very common and virtually all human beings will develop them as they age. Some people may be born with cataracts or develop them early due to certain medical conditions or trauma. Cataract surgery is a technically challenging, sophisticated, and elegant procedure that is the most commonly performed surgery in the world. After the clouded lens is removed, a permanent artificial lens is implanted in the eye. Occasionally, complications can occur during cataract surgery which can make placement of this lens implant difficult. If this occurs, a vitreoretinal surgeon may intervene to removed any fragments of clouded lens that could not be removed, and to find a suitable location to implant the lens.
Endophthalmitis- Endophthalmitis refers to an infection within the eyeball itself (not on the outside like conjunctivitis/pink eye). It is a feared complication of any intraocular surgery or injection because its prognosis is poor. Depending on the visual acuity, this infection is either treated with surgery or by injection of antibiotics directly into the eye followed by very strong eye drops. Vitreoretinal surgeons are the only eye doctors that treat this condition. It is our most important emergency but luckily also the rarest. Signs of endophthalmitis after surgery include loss of vision, deep pain within the eye, increasing redness of the eye and usually occur 2-3 days after a procedure. There are other conditions that can mimic endophthalmitis so you must be evaluated by an ophthalmologist as they are treated differently. Occasionally, patients can develop endophthalmitis without undergoing a surgical procedure if they have an underlying systemic infection.
Uveitis- The uvea is the middle coat of the eye and includes the iris, ciliary body, and choroid. It can become inflamed for a variety of idiopathic, autoimmune, or infectious reasons. It is important to determine the underlying cause of uveitis so it can be properly treated to prevent long term systemic and ocular problems. Retina specialists help diagnose and treat patients with posterior uveitis. Signs and symptoms of posterior uveitis include vision loss, pain, redness, and floaters.
Inherited retinal dystrophies- There are many different genetic conditions that can cause the rods and/or cones in the retina (specialized cells that detect light) to malfunction. These diseases can range from very mild to very severe. Treatment is limited at this time but we are learning more about the genetic causes of these diseases and gene therapies are being developed to treat specific mutations. In fact, there is an FDA approved gene therapy for people with an RPE65 mutation. Other treatment modalities include dietary modification, specific supplements, certain medications, retinal prostheses, and low vision rehabilitation.
Ocular trauma- Unfortunately serious accidents can happen that damage the eye. When penetrating trauma occurs, an ophthalmologist will attempt to surgically close the wound to the eye to restore the integrity of the globe. Many secondary complications can occur and these are normally only dealt with by a vitreoretinal surgeon. This can include dislocated lens, retinal tears, vitreous hemorrhage, retina detachment, retained intraocular foreign bodies and endophthalmitis. The final visual prognosis depends on the severity of the trauma and secondary complications.
Retinopathy of Prematurity- The retina does not finish developing until after birth. Babies that are born prematurely are at risk of developing retinal problems which can be treatable when caught in time. Retina specialists work with pediatric eye specialists to help diagnose and treat this problem. If not treated early enough, babies can go on to develop retinal detachments which are difficult to repair even with surgery. Looking after babies with this condition is some of the most important work we do as retinal specialists.
Choroidal nevus, melanoma, and other Intraocular tumours- Intraocular tumours are very rare. Just as you can develop moles on your skin, you can also develop moles inside your eye. These moles are called choroidal nevi. Rarely, a nevus can turn into a melanoma (cancer) within your eye. Patients with nevi should be monitored periodically to ensure they are not growing. Other cancers that affect the eye include metastases from systemic cancers and lymphoma. Children can rarely develop a tumour called retinoblastoma that is life threatening if not diagnosed early. Your pediatrician will screen your child for this by looking at the eye to ensure it has a normal "red reflex" when observed through an ophthalmoscope. If you or your child are diagnosed with an intraocular tumour you will be referred to a specialized major ocular oncology center where confirmation of diagnosis and treatment will be carried out.