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Retinopathy is any damage to the retina of the eyes, which may cause vision impairment. Retinopathy often refers to retinal vascular disease, or damage to the retina caused by abnormal blood flow. Age-related macular degeneration is technically included under the umbrella term retinopathy but is often discussed as a separate entity. Retinopathy, or retinal vascular disease, can be broadly categorized into proliferative and non-proliferative types. Frequently, retinopathy is an ocular manifestation of systemic disease as seen in diabetes or hypertension. Diabetes is the most common cause of retinopathy in the U.S. as of 2008. Diabetic retinopathy is the leading cause of blindness in working-aged people. It accounts for about 5% of blindness worldwide and is designated a priority eye disease by the World Health Organization.
Diabetic retinopathy, also known as diabetic eye disease (DED), is a medical condition in which damage occurs to the retina due to diabetes mellitus. It is a leading cause of blindness in developed countries.
Retinopathy of prematurity (ROP), also called retrolental fibroplasia (RLF) and Terry syndrome, is a disease of the eye affecting prematurely born babies generally having received neonatal intensive care, in which oxygen therapy is used due to the premature development of their lungs. It is thought to be caused by disorganized growth of retinal blood vessels which may result in scarring and retinal detachment. ROP can be mild and may resolve spontaneously, but it may lead to blindness in serious cases. Thus, all preterm babies are at risk for ROP, and very low birth-weight is an additional risk factor. Both oxygen toxicity and relative hypoxia can contribute to the development of ROP.
Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is a surgical emergency.
Uveitis is the inflammation of the uvea, the pigmented layer that lies between the inner retina and the outer fibrous layer composed of the sclera and cornea. The uvea consists of the middle layer of pigmented vascular structures of the eye and includes the iris, ciliary body, and choroid. Uveitis is described anatomically, by the part of the eye affected, as anterior, intermediate or posterior, from front to back. In the panuveitic form, all parts are involved. The commonest is the anterior form. Symptoms include pain, floaters and blurred vision, and clinical examination may show redness and an irregular pupil, while ophthalmic examination shows dilated ciliary blood vessels and the presence of cells in the anterior chamber. Uveitis may arise spontaneously and associated with some genetic factors, or be associated with a wide range of conditions including autoimmune disease and infections. While the eye is a relatively protected environment, its immune mechanisms may be overcome resulting in inflammation and tissue destruction associated with T-cell activation. The incidence is approximately 1:4500, most commonly between the ages of 20–60.
Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors, inner retinal cells, and the ganglion cells. Electrodes are placed on the surface of the cornea or on the skin beneath the eye to measure retinal responses. Retinal pigment epithelium (RPE) responses are measured with an EOG test with skin-contact electrodes placed near the canthi. During a recording, the patient's eyes are exposed to standardized stimuli and the resulting signal is displayed showing the time course of the signal's amplitude (voltage). Signals are very small, and typically are measured in microvolts or nanovolts. The ERG is composed of electrical potentials contributed by different cell types within the retina, and the stimulus conditions can elicit stronger response from certain components.
Central serous chorioretinopathy, also known as central serous retinopathy (CSR), is an eye disease that causes visual impairment, often temporary, usually in one eye. When the disorder is active it is characterized by leakage of fluid under the retina that has a propensity to accumulate under the central macula. This results in blurred or distorted vision (metamorphopsia). A blurred or gray spot in the central visual field is common when the retina is detached. Reduced visual acuity may persist after the fluid has disappeared.
Kearns–Sayre syndrome (KSS), oculocraniosomatic disorder or oculocranionsomatic neuromuscular disorder with ragged red fibers is a mitochondrial myopathy with a typical onset before 20 years of age. KSS is a more severe syndromic variant of chronic progressive external ophthalmoplegia, a syndrome that is characterized by isolated involvement of the muscles controlling movement of the eyelid and eye. This results in ptosis and ophthalmoplegia respectively. KSS involves a combination of the already described CPEO as well as pigmentary retinopathy in both eyes and cardiac conduction abnormalities. Other symptoms may include cerebellar ataxia, proximal muscle weakness, deafness, diabetes mellitus, growth hormone deficiency, hypoparathyroidism, and other endocrinopathies. In both of these diseases, muscle involvement may begin unilaterally but always develops into a bilateral deficit, and the course is progressive. This discussion is limited specifically to the more severe and systemically involved variant.
Progressive outer retinal necrosis (PORN) syndrome is a form of chorio-retinitis, an infection in the retina, the back of the eye. The disease is most commonly caused by the Varicella zoster virus and is found almost exclusively in patients with HIV/AIDS. Progressive outer retinal necrosis is the second most common opportunistic retinal infection in North America among people with AIDS. The reason this disease process is considered opportunistic is precisely because it only presents in patients with AIDS, a disease that attacks and weakens the immune system, making space for other infections, like Varicella zoster virus (VZV) and Herpes simplex virus (HSV), to attack the body.
Ocular ischemic syndrome is the constellation of ocular signs and symptoms secondary to severe, chronic arterial hypoperfusion to the eye. Amaurosis fugax is a form of acute vision loss caused by reduced blood flow to the eye; it may be a warning sign of an impending stroke, as both stroke and retinal artery occlusion can be caused by thromboembolism due to atherosclerosis elsewhere in the body. Consequently, those with transient blurring of vision are advised to urgently seek medical attention for a thorough evaluation of the carotid artery. Anterior segment ischemic syndrome is a similar ischemic condition of anterior segment usually seen in post-surgical cases. Retinal artery occlusion leads to rapid death of retinal cells, thereby resulting in severe loss of vision.
Cotton wool spots are opaque fluffy white patches on the retina of the eye that are considered an abnormal finding during a funduscopic exam. Cotton wool spots are typically a sign of another disease state, most common of which is diabetic retinopathy. The irregularly shaped white patches are a result of ischemia, or reduced blood flow and oxygen, in the retinal nerve fiber layer, which is located in the distribution of the capillaries of the superficial layer of the retina. These areas with reduced blood flow reflect the obstruction of axoplasmic flow due to mechanical or vascular causes and the consequential accumulation as a result of decreased axonal transport. This reduced axonal transport can then cause swelling or bulging on the surface layer of the retina, increasing the potential for nerve fiber damage.
Acute retinal necrosis (ARN) is a medical inflammatory condition of the eye. The condition presents itself as a necrotizing retinitis. The inflammation onset is due to certain herpes viruses, varicella zoster virus (VZV), herpes simplex virus and Epstein–Barr virus (EBV).
White dot syndromes are inflammatory diseases characterized by the presence of white dots on the fundus, the interior surface of the eye. The majority of individuals affected with white dot syndromes are younger than fifty years of age. Some symptoms include blurred vision and visual field loss. There are many theories for the etiology of white dot syndromes including infectious, viral, genetics and autoimmune.
Purtscher's retinopathy is a disease where part of the eye (retina) is damaged. Usually associated with severe head injuries, it may also occur with other types of trauma, such as long bone fractures, or with several non-traumatic systemic diseases. However, the exact cause of the disease is not well understood. There are no treatments specific for Purtscher's retinopathy, and the prognosis varies. The disease can threaten vision, sometimes causing temporary or permanent blindness.
Bascom Palmer Eye Institute is the University of Miami School of Medicine's ophthalmic care, research, and education center. The institute is based in the Health District of Miami, Florida, and has been ranked consistently as the best eye hospital and vision research center in the nation.
Michael David Abràmoff is a Dutch-American ophthalmologist, computer scientist and entrepreneur. He is the Robert C. Watzke Professor of Ophthalmology and Visual Sciences at the Roy J. and Lucille A. Carver College of Medicine at the University of Iowa. He is the Founder and Executive Chairman of Digital Diagnostics, of Iowa City, called by Wired Magazine "the bolder AI company", and which received the first FDA marketing authorization for an autonomous diagnostic AI system in any field of medicine.
Autoimmune retinopathy (AIR) is a rare disease in which the patient's immune system attacks proteins in the retina, leading to loss of eyesight. The disease is poorly understood, but may be the result of cancer or cancer chemotherapy. The disease is an autoimmune condition characterized by vision loss, blind spots, and visual field abnormalities. It can be divided into cancer-associated retinopathy (CAR) and melanoma-associated retinopathy (MAR). The condition is associated with retinal degeneration caused by autoimmune antibodies recognizing retinal proteins as antigens and targeting them. AIR's prevalence is extremely rare, with CAR being more common than MAR. It is more commonly diagnosed in females in the age range of 50–60.
John Donald MacIntyre Gass was a Canadian-American ophthalmologist, one of the world's leading specialists on diseases of the retina. He was the first to describe many macular diseases.
Indocyanine green angiography (ICGA) is a diagnostic procedure used to examine choroidal blood flow and associated pathology. Indocyanine green (ICG) is a water soluble cyanine dye which shows fluorescence in near-infrared range, with peak spectral absorption of 800-810 nm in blood. The near infrared light used in ICGA penetrates ocular pigments such as melanin and xanthophyll, as well as exudates and thin layers of sub-retinal vessels. Age-related macular degeneration is the third main cause of blindness worldwide, and it is the leading cause of blindness in industrialized countries. Indocyanine green angiography is widely used to study choroidal neovascularization in patients with exudative age-related macular degeneration. In nonexudative AMD, ICGA is used in classification of drusen and associated subretinal deposits.
Sickle cell retinopathy can be defined as retinal changes due to blood vessel damage in the eye of a person with a background of sickle cell disease. It can likely progress to loss of vision in late stages due to vitreous hemorrhage or retinal detachment. Sickle cell disease is a structural red blood cell disorder leading to consequences in multiple systems. It is characterized by chronic red blood cell destruction, vascular injury, and tissue ischemia causing damage to the brain, eyes, heart, lungs, kidneys, spleen, and musculoskeletal system.
References
- ↑ Quillen DA, Davis JB, Gottlieb JL, Blodi BA, Callanan DG, Chang TS, et al. The white dot syndromes. American Journal of Ophthalmology. 2004;137(3):538-50.
- ↑ Carrasco L, Ramos M, Galisteo R, Pisa D, Fresno M, Gonzalez ME. Isolation of Candida famata from a Patient with Acute Zonal Occult Outer Retinopathy. J Clin Microbiol. 2005;43(2):635-40.
- 1 2 3 "AZOOR". American Academy of Ophthalmology.Hugo R. Salcedo, MD, Koushik Tripathy, MD (AIIMS), FRCS (Glasgow) and Vinay A. Shah M.D.