Introduction Houston Retina Associates

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3 Introduction This book was written by Houston Retina Associates to provide our patients with basic knowledge about retinal anatomy, an introduction to some of the diagnostic tests and treatments used by retinal specialists, and a sampling of the more common retinal diseases and conditions. If you are reading this book, you or someone close to you may have been asked to see a retina specialist. We hope that the information contained within this book will better prepare you to make informed decisions about possible tests and treatments that may be recommended. The information contained within this book is not intended to be an all encompassing list of retinal diseases and conditions, and it should not substitute or supplant any advice from your doctor. In addition, the treatments outlined within are current as of the publishing date of this book. Science and medicine are constantly evolving, and your eye doctor and retina specialist are the best sources of information about the latest and best treatments available. 3

4 Table of Contents Our Mission...Page 4 Our Doctors...Page 5 What is a Retina Specialist?...Page 6 Basic Eye Anatomy...Page 7 The Retina and Macula...Page 9 Diagnostic Tests The Retinal Examination...Page 12 o Optical Coherence Tomography (OCT)...Page 15 o Digital Fluorescein Angiography and Fundus Photography...Page 16 o Digital Indocyanine Green (ICG) Angiography...Page 18 o Ocular Ultrasound...Page 19 o 4 Common Conditions Macular Degeneration...Page 20 o Diabetic Retinopathy...Page 26 o Flashes & Floaters...Page 34 o Retinal Tears & Retinal Detachment...Page 36 o Epiretinal Membrane & Macular Pucker...Page 40 o Macular Hole...Page 42 o

5 Common Conditions Cont d Lattice Degeneration & Peripheral Retinal Holes...Page 44 o Retinal Vein Occlusion...Page 46 o Central Serous Retinopathy...Page 48 o Pigmented Retinal Lesions & Choroidal Nevus...Page 50 o Cystoid Macular Edema...Page 52 o Uveitis...Page 53 o Retained Lens Material...Page 54 o Common Treatments Laser Photocoagulation...Page 56 o Vitrectomy Surgery...Page 58 o Intravitreal Injections...Page 60 o Photodynamic Therapy...Page 61 o Driving Directions...Page 62 Amsler Grid...Page 64 Our Offices...Back Cover Your eye doctor may ask you to read one or more sections 5

6 Our Mission Houston Retina Associates consists of Board Certified Ophthalmologists devoted to excellence in diagnosing and treating diseases of the retina, macula, and vitreous. Our practice focuses on a single subspecialty of eye care, which in turn, enables us to stay focused on the latest advances in our field. Our mission is to provide the highest quality medical care with a personal approach that is sensitive to our patient s needs. We see patients with a wide variety of eye conditions including macular degeneration, diabetic eye disease, epiretinal membrane, macular hole, retinal detachment, retinal tear, retinal vascular disease, eye trauma, inflammatory eye disease, and various other conditions. We will work closely with your eye doctor and primary care physician during the course of your retinal treatment. When your retinal treatment is complete, you will return to your referring eye doctor for continuing general eye care. Because a well-informed patient is vital to the doctor-patient relationship, we will carefully review your diagnosis and our treatment recommendations with you. We encourage you to ask questions during your visit and to call us if questions arise later. We hope you find this information helpful, and we look forward to caring for you. 4

7 Our Doctors Dr. John J. Alappatt graduated magna cum laude with Alpha Omega Alpha honors from a 6-year combined undergraduate and medical school program at Northeastern Ohio Universities. He went on to complete his general ophthalmology residency at the University of Cincinnati, followed by subspecialty training in retinal diseases at the University of Texas and Parkland Hospital in Dallas. Following his subspecialty training, Dr. Alappatt accepted a position as full-time faculty at the University of Texas Southwestern Medical School where he conducted research in retinal diseases and mentored young retinal surgeons. Dr. Alappatt continues to teach as Clinical Assistant Professor at Baylor College of Medicine. Dr. Michael K. Lam grew up in Sugar Land, Texas. After graduating from Clements High School, he attended college at the University of California at Berkeley. While at U.C. Berkeley he earned the prestigious Regents scholarship and a degree in Biochemistry with the highest honors for academic achievement. He returned to Texas to attend medical school at the University of Texas Southwestern. Afterwards, he went on to complete his general ophthalmology residency at the University of Chicago, where he was elected Chief Resident in Ophthalmology. Upon completion of his residency, he returned to Texas to complete his retinal subspecialty training at the University of Texas and Parkland Hospital in Dallas. Dr. Lam currently serves as Clinical Assistant Professor at Baylor College of Medicine. Dr. Lee T. Tran grew up in Houston and graduated summa cum laude with a dual degree in chemistry and biology from the University of St. Thomas. He received his medical degree from Baylor College of Medicine. Dr. Tran completed his ophthalmology residency and vitreoretinal fellowship at the University of Texas Medical School at Houston, where he served as chief resident and received the Outstanding Fellow in Ophthalmology Award. Dr. Tran worked in South Texas in a busy retina practice prior to moving home and joining Houston Retina Associates. He has conducted research on vitreoretinal surgery, age-related macular degeneration, diabetic retinopathy, and diabetic macula edema. Dr. Tran teaches vitreoretinal surgery as Clinical Assistant Professor at Baylor College of Medicine. He has a passion for mission work and has traveled to Honduras and Vietnam to provide medical and surgical care for disadvantaged patients. 5

8 What is a Retina Specialist? Retina specialists are Ophthalmologists (eye surgeons) who have specialized training in the treatment of diseases of the retina, macula, and vitreous. Typically, a retina specialist has two years of additional training after completion of a general eye surgery residency. This additional subspecialty training is called a vitreoretinal fellowship. During a vitreoretinal fellowship, doctors learn specialized surgical and diagnostic techniques to treat a variety of retinal diseases. Common retinal diseases treated by retina specialists will be outlined in the latter parts of this book. A partial list includes: macular degeneration, diabetic eye disease, retinal detachment, epiretinal membrane, macular hole, retinal tear, flashes and floaters, retinal vascular disease, eye trauma, inflammatory eye disease, and various other retinal conditions. The doctors of Houston Retina Associates are retina specialists who focus exclusively on the medical and surgical treatment of retinal disease. Almost all of the patients seen by Houston Retina Associates have been referred from other eye doctors. Sometimes, we are asked to treat and stabilize your retinal condition. Other times, we serve as consultants and will provide a second opinion about your retinal care. We will always try to work closely with your primary eye doctor, because this helps us achieve the best visual outcome for our patients. 6

9 Basic Eye Anatomy 7

10 Basic Eye Anatomy In order to understand the variety of diseases diagnosed and treated by retina specialists, it would be useful to review some basic eye anatomy. The eye is a rather complex organ that functions very much like a camera. A camera has different components that serve separate functions. For example, a camera requires a lens to focus light and film in the back of the camera to capture the image. A camera also has a shutter which opens and closes, determining how much light to let into the back of the camera. Similar to a camera, the eye has separate parts which also serve different functions. The eye has a lens system (cornea, lens) which focuses light, and a shutter (iris) which determines how much light enters the eye. This book deals with the film component of the eye called the retina. Similar to the location of camera film, the retina is housed in the back of the eye. Initially, light passes through the cornea and lens located in the front of the eye. These two structures serve to focus the light entering the eye. After the light passes through the lens, it travels through the clear gel in the middle of the eye, called the vitreous gel. The vitreous gel makes up the majority of the eye s volume as it fills the center of the eye cavity. After traveling through the middle of the eye, the light is captured by the retina on the back surface of the eye. The retina transforms the light into a visual image, which is sent out of the eye to the brain through the optic nerve. 8

11 The Retina As a whole, the retina is very much like the film inside the back of a camera. It is a thin layer of nerve tissue that forms the inside lining of the eyeball. The retina receives light and sends an image signal to the brain. It covers most of the inner lining of the eye, except for the front of the eye where light enters. In addition to the retina, the back of the eye has two additional layers of cells, called the retinal pigment epithelium (RPE) and choroid. The retinal pigment epithelium is important for the retina s metabolism. For example, it stores and processes Vitamin A, which is a critical nutrient for the retina. The choroid also performs an important supporting role for the retina. It is a thick layer of blood vessels, which delivers oxygen and nutrients to the retinal cells. Diseases that affect the RPE and choroid can lead to a poorly functioning retina and even death of the retinal cells. 9

12 The Macula & Peripheral Retina The macula is the visual center of the retina. The color of the macula is slightly darker than the surrounding retina and it is located near the entry point of the optic nerve, which connects the eye to the brain. The macula and optic nerve are located in the center and back wall of the eye. The peripheral retina is the part of the retina that covers the inside walls of the eye located on the top, bottom, left, and right. The peripheral retina is responsible for peripheral or side vision. 10

13 The Macula & Peripheral Retina The macula is a special part of the retina that is located in the very center of the retina. Because of its location, the macula is critical for detailed central vision. Certain visual tasks, such as reading and focusing on small objects, are performed exclusively by the macula. The macula is particularly sensitive to certain diseases that affect vision. For example, age-related macular degeneration is a condition that tends to affect the macula and usually spares the other areas of the retina. Diseases and conditions that affect the macula may affect central vision and lead to blind spots, visual distortion, and central visual blur. The peripheral retina is the non-central part of the retina. The majority of the retinal surface is considered peripheral retina, which is responsible for side vision, also known as peripheral vision. The peripheral retina is important for seeing out of the corner of your eye, and it also determines the overall size of your visual field. The peripheral retina is also sensitive to certain diseases that affect vision. For example, a retinal detachment generally begins as a peripheral retinal problem. Peripheral retinal disease may manifest as a curtain coming down over one s visual field, or tunnel vision. 11

14 Diagnostic Tests The Retinal Examination When visiting with a retina specialist, he or she will use instruments and special lenses designed to directly visualize the retina. Direct retinal examination is perhaps the most important part of the evaluation process. The tools used by retina specialists are also used by primary eye doctors. Usually, patients are already familiar with these instruments. Most of the time, eye drops will be used to dilate your pupils at the time of the retinal examination. Dilating the pupils allows the doctor to examine both the central and peripheral retina more completely. After the examination, the pupils may remain dilated for several hours. Most people are able to drive home after receiving dilating drops. However, we recommend bringing a friend or family member to drive home if you have never been dilated before or if you have had blurred vision in the past after receiving dilating drops. The slit lamp and the indirect ophthalmoscope are two instruments that retina specialists use to examine the retina. With special lenses and relatively bright lights, the retina itself can be visualized directly. Although the lights used during the retinal examination can be uncomfortable for patients, they are not harmful to the eye. If abnormalities are detected during the retinal examination, additional diagnostic testing may be necessary for a more detailed or specific evaluation. 12

15 Diagnostic Tests The Retinal Examination Slit-lamp examination: The slit-lamp microscope is a tool used to examine the retina. With the patient seated upright, a bright light is used to illuminate the inside of the eye. With the assistance of a magnifying lens, the eye doctor uses a slit-lamp to see the macula and optic nerve in great detail. 13

16 Diagnostic Tests The Retinal Examination Indirect examination: The indirect ophthalmoscope is another magnifying tool used to examine the peripheral retina. The patient is usually examined sitting upright or lying back. The doctor wears a headpiece containing special mirrors, lenses, and a light source. Combined with a handheld lens, the doctor is able to examine different parts of the peripheral retina in detail. Sometimes, the indirect examination is combined with a maneuver called scleral indentation, where gentle pressure is placed on the eyelids to examine the most peripheral parts of the retina. 14

17 Diagnostic Tests Optical Coherence Tomography (OCT) Optical Coherence Tomography, OCT is a non-invasive technology used for imaging the retina. OCT allows doctors to see cross-sectional images of the retina and has revolutionized the early detection and treatment of eye conditions such as macular degeneration, macular holes, epiretinal membranes, vitreomacular traction, macular swelling, and optic nerve damage. This test has clinical applications for early diagnosis of many retinal and macular diseases since subtle changes may be detected before diseases are evident by examination alone. OCT can also be used to track changes in retinal disease by measuring the thickness of the retina quantitatively. Therefore, it can be an important tool in monitoring treatment of retinal diseases, such as diabetic macular edema and macular degeneration. 15

18 Diagnostic Tests Digital Fluorescein Angiography and Retinal Photography A large digital camera, a computer server, and a color monitor are the essential components of a digital photography and angiography system. High resolution photographs are taken of the patient s retina by a trained retinal photographer, and the results are available immediately for review by the doctor. 16

19 Diagnostic Tests Digital Fluorescein Angiography and Retinal Photography Digital retinal photography is performed with a large digital camera that takes high resolution photographs of the retina and macula. The test is performed with the patient seated in a chair, and both the camera and photographer facing the patient. The images are available immediately for review on a computer monitor by both the doctor and the patient. Digital retinal photography has many clinical uses. For example, it is particularly useful for accurately documenting the extent of retinal disease at one point in time, for comparison at a later date. Fluorescein (a yellow synthetic dye) angiography may also be used to enhance the digital photographs in certain retinal diseases. Fluorescein is injected into a vein in the arm and circulates quickly to the eye. When the digital camera is used with certain light filters, fluorescein will highlight blood vessels and most areas of retinal disease. Clinical decision making for a variety of retinal diseases depends on fluorescein angiography. For example, fluorescein angiography is commonly used to guide treatment for agerelated macular degeneration, diabetic retinopathy, and retinal vascular occlusions. In the past, 35 mm film was used for retinal photography and angiography. This requires waiting for the film to be developed for a clinical decision to be made. This can take several days if the film is sent off-site for development. With the latest technology, digital angiography and photography provide instant and accurate results viewable on a computer monitor or by hard copy from a photographic printer. 17

20 Diagnostic Tests Digital ICG Angiography Indocyanine Green (ICG) angiography focuses on an important layer of blood vessels just beneath the retina called the choroid. These blood vessels serve several important roles in the eye, including supplying the retina with oxygen and nutrients. The choroidal vessels cannot be directly visualized by retinal examination or fluorescein angiography, but they can be imaged using ICG angiography. In a manner similar to fluorescein angiography, ICG dye is injected into a vein in the arm. A digital camera is used with certain light filters, to highlight the choroidal blood vessel layer located underneath the retinal layers. ICG angiography can be performed as a stand-alone test. However, it is often used in conjunction with fluorescein angiography to provide a more complete picture of the blood vessels in the back of the eye. ICG imaging of the choroidal vessels is useful when evaluating certain types of retinal diseases. Age-related macular degeneration and inflammatory diseases of the retina are two diseases where ICG can be particularly helpful. For example, ICG angiography can be used as a supplement to fluorescein angiography to diagnose the wet form of macular degeneration that may be undetectable with fluorescein angiography alone. 18

21 Diagnostic Tests Ocular Ultrasound Ocular ultrasound is a technique in which a small ultrasound probe is used to image the eye. Sound waves transmitted from the probe reflect differently through various layers of the eye, thus generating a virtual image. Conditions such as a dense cataract or vitreous hemorrhage can prevent a direct view of the retina. When a view to the back of the eye is not possible, the ultrasound probe can produce an image of the entire eye. Ultrasound can also be used to diagnose and make measurements of a tumor within the eye. 19

22 Macular Degeneration Macular degeneration is a term that includes a variety of eye diseases that affect central vision. Age-related macular degeneration (AMD) is by far the most common form of macular degeneration. AMD is caused by a premature aging of the cells in the area of retina responsible for detailed central vision. This area of the eye is called the macula. Age-related macular degeneration is the leading cause of legal blindness in people older than 55 years in the United States. The disease affects more than 15 million Americans, including 35% of Americans older than 75 years. Because overall life expectancy continues to increase, age-related macular degeneration has become a major public health problem. Symptoms of macular degeneration include central visual blur, distortion of images, and blind spots near the central vision. An Amsler Grid (see page 64) is a useful tool to test the central visual field and to detect early vision problems due to macular degeneration. Early stages of AMD may have no visual symptoms at all. Risk factors for age-related macular degeneration include increasing age, family history, and cigarette smoking. There are two major types of age-related macular degeneration: The initial stage of macular degeneration is called Non-exudative Dry macular degeneration. In some patients, a more aggressive form of macular degeneration can develop, called Exudative Wet macular degeneration. 20

23 Macular Degeneration These photographs illustrate how macular degeneration might affect one s vision. The photograph to the right is blurred, distorted, and contains a blind spot in the middle of the image. Photographs credit: National Eye Institute, National Institutes of Health 21

24 Non-exudative ( Dry ) Macular Degeneration Multiple, small, yellowish deposits develop underneath the central retina called drusen. Drusen are the main feature of dry macular degeneration. As drusen accumulate underneath the central retina in an area called the macula, the macula can become thin and the retinal cells begin to function poorly. Many people with drusen have excellent vision and no symptoms at all. However, some develop mild to moderate vision loss if the drusen worsen and the retinal cells are significantly affected. When visual loss develops, this generally happens slowly over a period of years. Most people with age related macular degeneration begin with the dry form of the disease. The dry form accounts for 90% of all cases of age-related macular degeneration. Dry AMD progresses slowly, and most patients maintain useful vision throughout life. 22

25 Exudative ( Wet ) Macular Degeneration: Choroidal neovascularization CNV Newly-formed abnormal blood vessels, called choroidal neovascularization, are the hallmark of wet macular degeneration. These abnormal blood vessels grow between the retina and the deeper layers of the eye wall, in the area of the macula. These blood vessels will spontaneously leak fluid, bleed, and scar the retina. This process causes distortion and damage of the central retina. Vision distortion, visual blur, and/or a blind spot can develop suddenly with the development of choroidal neovascularization. Most patients who develop wet macular degeneration have some degree of preexisting dry macular degeneration. Although wet macular degeneration affects only 10% of people who have agerelated macular degeneration, it accounts for the majority of people who have significant visual loss. More than 200,000 new cases of wet age-related macular degeneration occur each year in the US. 23

26 Treatment: Macular Degeneration Treatments: As there is no cure for aging, there is no cure for macular degeneration. However, proven treatments are available which can slow or halt the progression of the disease and sometimes improve vision in many patients. 1. Lifestyle Modifications: Smoking cessation is crucial in reducing the risk of AMD progression. Eating a diet rich in dark, leafy green vegetables and fish may also slow progression of the disease. Studies have shown that a poor diet and uncontrolled blood pressure could contribute to worsening of AMD. 2. Vitamins: The Age Related Eye Disease Study (AREDS) showed that antioxidants and vitamins reduce the risk of vision loss in patients with moderate to advanced dry agerelated macular degeneration. The nutrients evaluated by the AREDS are contained in several different formulations, which are now available over the counter. However, these formulations are not without risk. A consultation with your eye doctor is recommended to determine if vitamins may benefit you. 3. Injections: Several medicines have been proven effective for treatment of wet macular degeneration by injection directly into the eye. Lucentis, Avastin, and Eylea are medications that are commonly used to treat wet macular degeneration. These medications block a chemical substance that promotes the growth of abnormal blood vessels. Medication therapy is currently the area of most active research for AMD treatment. 4. Photodynamic Therapy: A light-activated drug called verteporfin (Visudyne ) is given intravenously. Shortly after the administration of the drug, a cold laser is used to close the abnormal vessels. Photodynamic therapy is used for treatment of wet macular degeneration. 5. Laser Treatment: Laser surgery was the first proven treatment for wet macular degeneration. Patients with neovascularization outside the center of vision may be treated with a hot laser to directly destroy the abnormal blood vessels. Only a small percentage of patients with wet macular degeneration are good candidates for this treatment. 24

27 Prognosis: Macular Degeneration The dry form accounts for 90% of all cases of AMD. Dry AMD progresses slowly, and most patients maintain useful vision throughout life. The wet form comprises 10% of all cases of AMD. Wet AMD is a leading cause of irreversible legal blindness in patients older than 55 in the United States. Approximately 60% of those who lose vision in one eye lose some vision in the other eye as well. When both eyes have wet AMD, quality of life can be severely affected. People rarely lose all of their vision from macular degeneration as the peripheral or side vision usually stays intact. Despite poor central vision, most people with macular degeneration are able to care for themselves and perform most of the activities of daily living. Treatments for macular degeneration are constantly evolving. Research and a better understanding of the disease process have led to new treatments and better visual outcomes for patients with AMD. With today s treatments, the visual prognosis for macular degeneration is better than it has ever been. 25

28 Diabetic Retinopathy Diabetes mellitus is one of the leading causes of irreversible blindness worldwide. In the United States, it is the most common cause of blindness in people younger than 65 years. Severe diabetic eye disease most commonly develops in people who have had diabetes mellitus for many years. High blood sugar and other abnormalities in metabolism found in people with diabetes mellitus can damage the blood vessels in the body. This damage to the blood vessels leads to poor circulation of blood to various parts of the body. Some of the most sensitive tissues to decreased blood flow and oxygen delivery include the feet, heart, kidneys, and eyes. The primary part of the eye affected by diabetes mellitus is the retina. Damage to the retinal blood vessels can lead to bleeding, retinal swelling, poor blood flow to the retina, and scarring of the retina. Diabetics that have better control of their blood sugar have fewer problems in the long run. The most important method of preventing eye disease related to diabetes is to maintain strict control of blood sugar. High blood pressure and high lipid or cholesterol levels must also be treated as these conditions exacerbate the retinal disease caused by diabetes. In mild cases of diabetic eye disease, vision may be stable for many years. Retinal laser, intraocular injection, and eye surgery can also improve vision in many cases. There are two major stages of diabetic retinopathy. The earlier stage of diabetic retinopathy is called non-proliferative diabetic retinopathy. The later, more advanced stage of diabetic retinopathy is called proliferative diabetic retinopathy. 26

29 Diabetic Retinopathy 27

30 Non-proliferative Diabetic Retinopathy Elevated blood sugar levels damage the walls of small blood vessels in the retina. These small blood vessels may begin to break down as damage accumulates with time. This leads to the accumulation of fluid (edema), protein deposits (hard exudates) and blood (hemorrhages) inside the retina. Diseased blood vessels will also develop thin walled pouches called microaneurysms, which are one of the earliest signs of diabetic eye disease. This process of blood vessel damage and leakage in the retina is called background diabetic retinopathy or non-proliferative diabetic retinopathy. If fluid accumulates in the central part of the retina (called the macula), this leads to a condition called diabetic macular edema. In severe cases of blood vessel damage, the small capillaries that supply the center of the vision (macula) may close permanently. This condition is called macular ischemia. Macular edema and macular ischemia are common causes of visual loss in diabetics. Central visual blur, visual distortion, and/or a blind spot are common symptoms in patients who have moderate to severe macular disease from non-proliferative diabetic retinopathy. Many patients with non-proliferative diabetic retinopathy have the early stages of the disease and do not require treatment. However, scheduled retinal examinations by an eye doctor are always necessary for patients with diabetic retinopathy. 28

31 Treatment: Non-proliferative Diabetic Retinopathy 1. Laser Treatment: Non-proliferative diabetic retinopathy is treated with laser when there is swelling of the macula. This swelling is called macular edema. Laser treatment is performed in the office and involves focusing a beam of laser light to treat leaking blood vessels and areas of retinal swelling. Macular photocoagulation has been proven to reduce the risk of vision loss from macular edema. 2. Intraocular Injections: Diabetic macular edema that is resistant to treatment with laser alone, may also be treated with other therapies. Intraocular injections of medicines (e.g. anti-inflammatory steroid injections, Avastin, and Lucentis ) may be helpful for reducing the macular swelling in some cases. 3. Vitrectomy Surgery: In certain cases, the vitreous gel and membranes on the surface of the retina can contribute to macular edema. Vitrectomy surgery may be useful in these cases to reduce the macular swelling. 29

32 30 Proliferative Diabetic Retinopathy

33 Proliferative Diabetic Retinopathy Damage to the blood vessels caused by high blood sugar eventually leads to decreased blood flow and lower amounts of oxygen delivered to the retina. As a response to poor oxygen delivery to the retina, the body may create new blood vessels that grow on the retinal surface. The process of new blood vessel formation is called retinal neovascularization. Retinal neovascularization is the hallmark of proliferative diabetic retinopathy. While new blood vessels may sound like a good thing, they are actually more harmful than beneficial. The new blood vessels are extremely fragile and unstable. If left untreated, neovascularization can lead to bleeding and scar tissue formation inside the eye. The scar tissue can contract and pull on the retina causing a tractional retinal detachment. This often results in severe vision loss. In advanced stages of the disease, this vision loss may be permanent. Early detection and treatment is important to prevent vision loss from proliferative diabetic retinopathy. In severe cases, neovascularization can develop in the front of the eye on the iris (the colored part of the eye). If abnormal vessels develop on the iris, they can block the filter that drains fluid from the eye, causing the pressure inside the eye to increase dramatically. This condition is called neovascular glaucoma and can lead to eye pain and further vision loss. 31

34 Treatment: Proliferative Diabetic Retinopathy Laser treatment for proliferative diabetic retinopathy retinopathy Vitrectomy surgery to remove blood inside the eye 32

35 Treatment: Proliferative Diabetic Retinopathy Proliferative diabetic retinopathy is treated with both laser and operating room surgery. The hallmark of proliferative diabetic retinopathy is retinal neovascularization, or abnormal new blood vessels growing on the retina. These blood vessels may bleed spontaneously and can cause serious scarring of the retina. Laser Treatment: Pan-retinal photocoagulation (PRP) is a laser technique that stimulates shrinkage of these abnormal vessels. This procedure is performed in the office under topical or local anesthesia. Pan-retinal photocoagulation has been proven to reduce the risk of vision loss due to proliferative diabetic retinopathy. Vitrectomy Surgery: If extensive new blood vessel growth, scar tissue formation, or bleeding inside the eye occurs, a surgical procedure known as a vitrectomy may be recommended. This surgery is performed in an operating room at a hospital or ambulatory surgery center. During a vitrectomy for proliferative diabetic retinopathy, blood inside the eye is removed and replaced with a clear fluid. Scar tissue is also removed from the retinal surface with delicate instruments. A vitrectomy surgery is often combined with laser treatment and/or retinal detachment surgery. 33

36 Flashes & Floaters Most of the eye s interior is filled with vitreous, a clear, thick, gel-like substance that has the consistency of raw egg whites. As we age, the center of the vitreous slowly liquefies. The vitreous gel, with it s liquid center, eventually collapses in upon itself and pulls away from the retina. Separation of the vitreous from the retina can happen rather suddenly. When the separation occurs, the fibers inside the vitreous can become dense and visible. These fibers appear as floaters, often described as black spots or cobwebs floating in one s field of vision. These floaters may also be accompanied by flashes of light (lightning streaks) in one s peripheral, or side vision. These flashes are caused by a pulling effect or traction that the vitreous has on the retina (the light sensitive part of the eye) as it separates from the retina. This mechanical pulling stimulates the retinal nerve cell to send an electrical signal to the brain. The brain interprets this signal as light, even though no light is there. 34

37 Flashes & Floaters This entire process is called a posterior vitreous detachment (PVD). In most cases, a PVD is harmless and requires no treatment. A posterior vitreous detachment is a common condition that can affect people of any age, but usually affects people over age 50. People who are nearsighted are also at increased risk for a posterior vitreous detachment. People who have a vitreous detachment in one eye are also likely to develop one in the other eye, although it may not happen until years later. In most cases, people do not notice vitreous detachment when it occurs or merely find it a minor annoyance because of the increase in floaters. Although a vitreous detachment does not usually threaten one s sight, occasionally, some of the vitreous fibers pull so hard on the retina that they create a tear in the retina. A retinal tear can then lead to a retinal detachment, which is a serious and sight-threatening condition. Retinal tears and retinal detachments should be treated promptly. If left untreated, a detached retina can lead to permanent vision loss in the affected eye. Those who experience a sudden increase in floaters or flashes of light should have an eye care professional examine their eyes as soon as possible. The only way to diagnose the cause of the problem is with a comprehensive eye examination. If a vitreous detachment has led to a retinal tear or detachment, early treatment can help prevent loss of vision. 35

38 36 Retinal Tears & Retinal Detachment

39 Retinal Tears & Retinal Detachment Retinal tears and detachments are sight-threatening conditions that are considered one of the few ocular emergencies. A retinal detachment can occur at any age, but it is more common in people over 40 years of age. It affects men more than women. It is estimated that 1 in 300 people develop a retinal detachment sometime during their life. The retina is a thin layer of nerve tissue that lines the inside of the eye. This nerve layer is analogous to the film inside a camera and is essential for sight. In certain abnormal conditions, the retina may separate from the inside wall of the eye and hang freely within the middle of the eye. This is called a retinal detachment. The most common sequence of events leading to a retinal detachment begins with the sudden collapse of the vitreous gel that fills the middle of the eye, called a posterior vitreous detachment (PVD). As the vitreous collapses, it may pull on the retina hard enough to cause the retina to tear. Retinal tears allow fluid to pass though the retina and move behind the retinal layer. As fluid accumulates behind the retina, it moves further away from the wall of the eye. This condition is called a retinal detachment and can result in severe loss of vision. Retinal detachments and retinal tears are treated with surgery. The type of operation depends on the nature of the retinal detachment. With modern surgical techniques, over 90 percent of patients with a retinal detachment can be successfully treated. Sometimes a second treatment is needed. The final visual result may not be known for up to several months following surgery. Visual results are best if the retinal detachment is repaired before the macula (the center region of the retina responsible for fine, detailed vision) becomes detached. 37

40 Retinal Tears & Retinal Detachment Scleral buckle for retinal detachment Vitrectomy surgery for retinal detachment 38

41 Treatment: Retinal Tears & Retinal Detachment 1. Retinal laser or retinal cryotherapy: Retinal tears and holes can be treated with either laser surgery or a freezing treatment called cryotherapy. During laser surgery, tiny laser spots are placed around the retinal hole to weld the retina into place. Cryotherapy freezes the area around the hole and also helps keep the retina from detaching. These procedures are usually performed in the doctor s office. 2. Vitrectomy: Tiny incisions are made in the sclera (white of the eye), and small instruments are placed into the eye to reattach the retina. A gas bubble is then injected into the eye to place pressure on the retina to help keep it attached. In addition, a laser is applied to the retina to hold the retina in place. During the healing process, the natural fluid of the eye gradually replaces the gas bubble and refills the eye. This surgery is usually performed in an operating room under local anesthesia with mild sedation. 3. Scleral buckle: A tiny synthetic band is attached to the outside of the eyeball to gently push the wall of the eye against the detached retina. During this procedure, cryotherapy or laser is also used to help hold the retina in place. This surgery is usually performed in an operating room under local anesthesia with sedation or general anesthesia. 4. Pneumatic retinopexy: A small gas bubble is injected into the eye that pushes the retina back against the wall of the eye. Laser or cryotherapy is then used to seal the retinal tear and help hold the retina in place. This surgery is performed in an office setting under topical or local anesthesia. Recovery time can be much quicker with pneumatic retinopexy. However, not all patients will be good candidates for this technique. 39

42 40 Epiretinal Membrane & Macular Pucker

43 Epiretinal Membrane & Macular Pucker Scar tissue can grow on the surface of the retina directly over the macula. This scar tissue causes the retina to wrinkle. The scar tissue on the surface of the retina is called an epiretinal membrane or macular pucker. An epiretinal membrane can cause visual loss as well as distorted or double vision. Epiretinal membranes occur more frequently in the older population with studies showing 2% prevalence in individuals aged 50 years and as much as 20% prevalence in individuals aged 75 years. Epiretinal membranes may be caused by a variety of eye problems. However, in most cases, an epiretinal membrane occurs in an otherwise healthy eye. Treatment: Surgical removal is the only treatment for the visual loss caused by an epiretinal membrane. However, if the vision is only mildly reduced, it is often best to observe the condition without performing surgery. If the visual loss or distortion is significant, a vitrectomy surgery may be performed to remove the membrane. During the procedure, the surgeon uses fine instruments to gently lift the membrane and peel it off the surface of the retina. This surgery can be performed under local anesthesia with sedation or general anesthesia. Prognosis: Studies have shown that between 65% and 90% of patients have better vision after surgery when tested on the eye chart. In most cases, visual improvement following epiretinal membrane surgery occurs gradually as the eye heals. Usually there is some visual improvement in the first six weeks, but final visual recovery is not achieved in many patients until at least six months after surgery. 41

44 Macular Hole The retina is a thin layer of nerve tissue that lines the inside of the eye. Its function is to gather light and send visual information to the brain. The macula is the area of the retina that is critical to central vision. A macular hole is a defect in the central retina. Most macular holes are caused by localized pulling on the retina by the jelly (vitreous) that normally fills the entire back of the eye. Early on, this pulling may cause mild visual blur as the retina becomes thinner. If a complete hole develops, patients are usually aware of a blind spot or distortion of their central vision. There are several different causes for macular holes. Chronic macular edema (i.e. diabetics) and trauma are two potential causes for macular holes. However, the overwhelming majority of macular holes develop spontaneously and have no underlying disease cause. Macular holes that have no underlying cause are called idiopathic macular holes. These are the most common type of macular holes. 42

45 Macular Hole Intraocular Injection: Small macular holes associated with abnormal pulling of the retina by the vitreous gel can be treated with an intraocular injection of a medicine called Jetrea. This medication dissolves the proteins that cause the abnormal pulling and allows for proper separation of the vitreous gel. Vitrectomy Surgery: Surgery is necessary to close large macular holes and macular holes which fail to close after non-surgical treatment with an intraocular injection. The goal of the surgery is to remove the gel (vitreous) that is pulling on the macula. This is done with a surgical procedure called a vitrectomy. The eye is filled with a large gas bubble. Following the surgery, the patient positions his/her head face down for the first 5-7 post-operative days. This permits the bubble to float to the back of the eye and maintains gentle pressure on the macular hole, which helps the hole close. The gas bubble disappears by itself in about 2 weeks. Prognosis: In most cases, visual improvement following macular hole surgery occurs gradually as the eye heals. Usually there is some visual improvement in the first few months. Many patients will continue to show gradual visual improvement up to 2 years following surgery. 43

46 44 Lattice Degeneration & Peripheral Retinal Holes

47 Lattice Degeneration & Peripheral Retinal Holes The majority of the retina s surface area is considered peripheral retina. The peripheral retina is responsible for side vision, also know as, peripheral vision. Some people have areas of thinning in the peripheral retina, known as lattice degeneration. The thinning can be severe enough that a retinal hole can develop. Usually, retinal holes and lattice degeneration cause no visual symptoms and are diagnosed on a routine eye examination. Lattice degeneration and retinal holes can be a precursor to a sight threatening condition called a retinal detachment. Treatments: Several factors will determine whether lattice degeneration or retinal holes need to be treated. Patients with lattice degeneration and retinal holes should have a careful and thorough assessment to determine the risk of a retinal detachment. Patients who are at high risk for retinal detachment may be treated preventatively. Preventative treatment usually consists of a laser treatment performed in the office. Prognosis: In the absence of a retinal detachment or other complications, patients with lattice degeneration and retinal holes should not develop visual problems. 45

48 Retinal Vein Occlusion When a peripheral retinal vein is occluded, this is called a branch retinal vein occlusion (BRVO). In a BRVO, swelling (edema) and hemorrhage are usually limited to one part of the retina. When the main vein draining the eye is occluded, this is called a central retinal vein occlusion (CRVO). In a CRVO, edema and hemorrhage can involve the entire retina resulting in more severe vision loss. 46

49 Retinal Vein Occlusion The retinal blood supply consists of arteries and veins. Arteries supply blood to the retina and veins drain blood from the retina. Occlusions, or blockages, in a retinal vein can occur for various reasons. The most common reason for a retinal vascular occlusion is atherosclerosis, or hardening of the arteries, that occurs with increasing age, high blood pressure, or high cholesterol. When a retinal vein is blocked, blood has difficulty draining from the eye. This leads to back pressure on the vessels and spillage of blood and fluid into the retinal tissue. If blood and fluid (macular edema) build up in the central retina, vision loss develops. Back pressure in the vein can also impair overall blood flow though the macula causing poor oxygen levels (macular ischemia). This can lead to permanent vision loss. Diagnosis: The diagnosis of a retinal vein occlusion can usually be made by a direct clinical examination of the retina. Fluorescein angiography is a useful clinical tool to determine the severity of the edema and ischemia. Optical coherence tomography (OCT) can be used to document the thickness of the retina and the amount of fluid in the macula. Treatment & Prognosis: Some patients with retinal vein occlusion are candidates for treatment. Laser treatment and intraocular injections are both used to treat retinal vein occlusions. Retinal laser is employed to lessen the amount of macular swelling in patients with branch retinal vein occlusions and to prevent a potentially serious complication called neovascularization in patients with central and branch retinal vein occlusions. In addition to laser treatment, intraocular injections with medicines such as steroids, Lucentis, Avastin, and Eylea are also commonly used treatments for macular swelling in central and branch retinal vein occlusions. Not all patients with retinal vein occlusions require treatment, and careful monitoring by an eye doctor will determine whether treatment is needed. The visual prognosis for CRVO and BRVO depends primarily upon the severity of the disease. 47

50 48 Central Serous Retinopathy (CSR)

51 Central Serous Retinopathy (CSR) Central serous retinopathy (CSR), also known as central serous chorioretinopathy (CSCR) is a problem that affects the macula. The exact cause of CSR is not well understood. Blood vessels that lie underneath the central retina begin to leak causing a blister of clear fluid to accumulate. This problem is somewhat similar to a water blister that forms under the skin. This water blister beneath the macula leads to blurred central vision, wavy or distorted vision, or a central blind spot. CSR affects men more often than women and usually occurs in young adults between the ages of 25 and 50. In certain people, stress is thought to be a potential cause of CSR. Diagnosis: Usually the diagnosis of CSR can be made by a direct clinical examination of the retina. Fluorescein angiography and optical coherence tomography (OCT) are also useful to confirm the diagnosis and gather additional information about the extent and severity of the problem. Treatment & Prognosis: Most patients with CSR do not require treatment, since the fluid usually absorbs gradually over a period of months. In cases where visual recovery is delayed or under specific clinical indications, laser treatment may be recommended to seal the fluid leak and help the vision improve more quickly. The majority of patients (80-90%) will have significant visual improvement as the water blister resolves. However, many will have some degree of mild visual blur or distortion after the active leakage has stopped, and there is a 40-50% chance of recurrent leakage in the same eye. 49

52 50 Pigmented Retinal Lesions & Choroidal Nevus

53 Pigmented Retinal Lesions & Choroidal Nevus The retina sits on top of two pigmented layers that line the inside of the eye. These pigmented layers are called the retinal pigment epithelium and the choroid. These two layers contain a pigment called melanin, which is common to other parts of the body, such as the skin. When pigment containing cells are clumped together in the skin, they can appear as freckles or moles. When the pigment containing skin cells begin to grow abnormally, as in a cancer, this is called a melanoma. Similar to the skin, the inside of the eye can have freckles, moles, and melanomas. Freckles and moles inside the eye are called choroidal nevi. Although very rare, some choroidal nevi have the potential to develop into choroidal melanomas. Diagnosis: Choroidal nevi must be monitored carefully by an eye doctor. When possible, nevi should be measured and their size documented with photography and ultrasound. Significant growth of a choroidal nevus should prompt suspicion of a choroidal melanoma. Treatment & Prognosis: Choroidal nevi (freckles and moles) are generally harmless and require no treatment. Choroidal melanomas are treated by a variety of methods depending on size, location, and stage of disease. Prognosis depends largely upon early detection. 51

54 Cystoid Macular Edema Cystoid macular edema (CME), or swelling of the macula, arises as a response to disease, injury, or in rare instances eye surgery. Clear fluid accumulates within layers of the macula causing visual blur and/or visual distortion. Diagnosis: Detecting CME can be difficult with a standard retinal examination since the swelling can be very subtle. Fluorescein angiography and optical coherence tomography (OCT) are excellent tests to diagnose CME. Treatment: The treatment of CME depends on the underlying cause and the severity of the swelling. Topical drops are often used as first line treatment. In more severe cases, an anti-inflammatory steroid injection can be given into or around the eye to reduce the macular swelling. Vitrectomy or laser surgery may be recommended if CME is caused by a condition which is not normally treatable by medicines alone. 52