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Intravitreal Administration
Intravitreal administration is a route of administration of a drug, or other substance, in which the substance is delivered into the vitreous humor of the eye. "Intravitreal" literally means "inside an eye". Intravitreal injections were first introduced in 1911 when Ohm gave an injection of air into the vitreous humor to repair a detached retina. In the mid-1940s, intravitreal injections became a standard way to administer drugs to treat endophthalmitis and cytomegalovirus retinitis. Epidemiology Intravitreal injections were proposed over a century ago however the number performed remained relatively low until the mid 2000s. Until 2001, intravitreal injections were mainly used to treat end-ophthalmitis. The number of intravitreal injections stayed fairly constant, around 4,500 injections per year in the US. The number of injections tripled to 15,000 in 2002 when triamcinolone injections were first used to treat diabetic macular oedema. This use continued to drive an increase to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three Main Layers Of The Eye
3 (three) is a number, numeral and digit. It is the natural number following 2 and preceding 4, and is the smallest odd prime number and the only prime preceding a square number. It has religious and cultural significance in many societies. Evolution of the Arabic digit The use of three lines to denote the number 3 occurred in many writing systems, including some (like Roman and Chinese numerals) that are still in use. That was also the original representation of 3 in the Brahmic (Indian) numerical notation, its earliest forms aligned vertically. However, during the Gupta Empire the sign was modified by the addition of a curve on each line. The Nāgarī script rotated the lines clockwise, so they appeared horizontally, and ended each line with a short downward stroke on the right. In cursive script, the three strokes were eventually connected to form a glyph resembling a with an additional stroke at the bottom: ३. The Indian digits spread to the Caliphate in the 9th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uveitis
Uveitis () is inflammation of the uvea, the pigmented layer of the eye 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, or panuveitic if all parts are involved. Anterior uveitis ( iridocyclitis) is the most common, with the incidence of uveitis overall affecting approximately 1:4500, most commonly those between the ages of 20–60. Symptoms include eye pain, eye redness, floaters and blurred vision, and ophthalmic examination may show dilated ciliary blood vessels and the presence of cells in the anterior chamber. Uveitis may arise spontaneously, have a genetic component, or be associated with an autoimmune disease or infection. While the eye is a relatively protected environment, its immune mecha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intravitreal Gene Therapy
Intravitreal gene therapy represents an approach to treating retinal diseases by delivering therapeutic genes directly into the vitreous humor of the eye. This method uses a viral vector, often an adeno-associated virus (AAV), to carry genetic material into retinal cells. Once inside, the therapeutic genes are expressed to address genetic deficiencies or modify biological pathways, offering a long-term or potentially permanent treatment ("biofactory approach") for conditions like wet age-related macular degeneration (AMD), diabetic macular edema, and inherited retinal dystrophies. Unlike traditional therapies requiring frequent injections, intravitreal gene therapy aims to reduce the treatment burden while improving efficacy potentially providing lifelong benefit. Advantages and challenges One of the key advantages of intravitreal administration is its minimally invasive nature compared to subretinal delivery. Intravitreal injections are already commonly used for administering ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye Drops
''Eye Drops'' is a television program on TechTV that showcased short computer animation movies and clips made using off the shelf 3D animation software. The show claimed to showcase all different types of animation, but only a very small number of shorts featured non-CG animation. Most animations are done completely by one person or by a small group of people. Series episodes Season one Episode 1, aired May 16, 2002 # ''It's Alive'' by Terry Ziegelman and Paul George Episode 2, aired May 23, 2002 # ''Bingo'' by Chris Landreth Episode 3, aired May 30, 2002 # ''Wild Card'' by Van Phan # ''Walk'' by Jeff Drew # ''Puppet'' by Anzovin Studio # ''Tung Fu'' by Gregory Lemons # ''F8 (part one)'' by Jason Wen # ''Airheads'' by Mike Wheeler # ''Serenade'' by Jason Judy, Paul Downs, and Michael Berger Episode 4, aired June 6, 2002 # ''Pasta for War'' by Zach Schlappi # Animation Lab: ''Rendering Transparent Materials'' by Henrik Wann Jensen # ''Ruby's Saloon'' by Kevin "Bubba" Lombar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Coherence Tomography Angiography
Optical coherence tomography angiography (OCTA) is a non-invasive Medical imaging, imaging technique based on optical coherence tomography (OCT) developed to visualize Retina#Blood supply, vascular networks in the human retina, choroid, skin and various animal models. OCTA may make use of speckle variance optical coherence tomography. OCTA uses motion contrast between cross-sectional OCT scans (B-frames) to differentiate blood flow from static tissue, enabling imaging of vascular anatomy. To correct for patient movement during scanning, bulk tissue changes in the axial direction are eliminated, ensuring that all detected changes are due to hemodynamics#Red blood cells, red blood cell movement. This form of Optical coherence tomography, OCT requires a very high sampling density in order to achieve the resolution needed to detect the tiny capillaries found in the retina. This has allowed OCTA to obtain detailed images of retinal vasculature in the human retina and become widely us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitrectomy
Vitrectomy is a surgery to remove some or all of the vitreous humor from the Human eye, eye. Anterior vitrectomy entails removing small portions of the vitreous humor from the front structures of the eye—often because these are tangled in an intraocular lens or other structures. ''Pars plana'' vitrectomy is a general term for a group of operations accomplished in the deeper part of the eye, all of which involve removing some or all of the vitreous humor—the eye's clear internal jelly. Even before the modern era, some surgeons performed crude vitrectomies. For instance, Dutch surgeon Anton Nuck (1650–1692) claimed to have removed vitreous by suction in a young man with an inflamed eye. In Boston, John Collins Warren (surgeon, born 1778), John Collins Warren (1778–1856) performed a crude limited vitrectomy for angle closure glaucoma. Anesthesia for vitrectomy Options for anesthesia for vitrectomy are general anaesthesia, local anesthesia, Topical anesthetic, topical a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypopyon
Hypopyon is a medical condition involving Inflammation#Cellular component, inflammatory cells in the anterior chamber of the human eye, eye. It is an exudate rich in white blood cells, seen in the anterior chamber, usually accompanied by redness of the conjunctiva and the underlying episclera. It is a sign of inflammation of the anterior uvea and iris (anatomy), iris, i.e. iritis, which is a form of uveitis, anterior uveitis. The exudate settles at the dependent aspect of the eye due to gravity. It can be sterile (in bacterial corneal ulcer) or not sterile (fungal corneal ulcer). Differential diagnosis Hypopyon can be present in a corneal ulcer. It can occur as a result of Behçet's disease, endophthalmitis, panuveitis/panophthalmitis, or adverse reactions to some drugs (such as rifabutin). Hypopyon is also known as ''sterile pus'' because it occurs due to the release of toxins and not by the actual invasion of pathogens. The toxins secreted by the pathogens mediate the outpouri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endophthalmitis
Endophthalmitis, or endophthalmia, is inflammation of the interior cavity of the eye, usually caused by an infection. It is a possible complication of all intraocular surgeries, particularly cataract surgery, and can result in loss of vision or loss of the eye itself. Infection can be caused by bacteria or fungi, and is classified as exogenous (infection introduced by direct inoculation as in surgery or penetrating trauma), or endogenous (organisms carried by blood vessels to the eye from another site of infection and is more common in people who have an immunocompromised state). Other non-infectious causes include toxins, allergic reactions, and retained intraocular foreign bodies. Intravitreal injections are a rare cause, with an incidence rate usually less than 0.05%. Endophthalmitis requires immediate medical attention to ensure the condition is diagnosed as soon as possible and treatment is started in order to reduce the risk of the person losing vision in the eye. Treatment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triamcinolone Acetonide
Triamcinolone acetonide, sold under the brand name Kenalog among others, is a synthetic compound, synthetic corticosteroid medication used topical medication, topically to treat various skin conditions, to relieve the discomfort of mouth sores, and by Joint injection, injection into joints to treat various arthropathy, joint conditions. It is also injected into lesion, lesions to treat inflammation in some parts of the body, particularly the skin. In nasal spray form, it is used to treat allergic rhinitis. It is used for the treatment of macular edema associated with uveitis. It is a more potency (pharmacology), potent derivative of triamcinolone, and is about eight times as potent as prednisone. Most forms of triamcinolone acetonide are Prescription drug, prescription drugs. In 2014, the U.S. Food and Drug Administration (FDA) made triamcinolone acetonide an over-the-counter drug in the United States in nasal spray form under the brand name Nasacort. It is available as a gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dexamethasone
Dexamethasone is a fluorinated glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive pulmonary disease (COPD), croup, brain swelling, eye pain following eye surgery, superior vena cava syndrome (a complication of some forms of cancer), and along with antibiotics in tuberculosis. In adrenocortical insufficiency, it may be used in combination with a mineralocorticoid medication such as fludrocortisone. In preterm labor, it may be used to improve outcomes in the baby. It may be given by mouth, as an injection into a muscle, as an injection into a vein, as a topical cream or ointment for the skin or as a topical ophthalmic solution to the eye. The effects of dexamethasone are frequently seen within a day and last for about three days. The long-term use of dexamethasone may result in thrush, bone loss, cataracts, easy bruising, or muscle weakness. It is in pregnancy category C in the United S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macular Edema
Macular edema occurs when fluid and protein deposits collect on or under the macula of the eye (a yellow central area of the retina) and causes it to thicken and swell ( edema). The swelling may distort a person's central vision, because the macula holds tightly packed cones that provide sharp, clear, central vision to enable a person to see detail, form, and color that is directly in the centre of the field of view. Cause The causes of macular edema are numerous and different causes may be inter-related. *It is commonly associated with diabetes. Chronic or uncontrolled diabetes type 2 can affect peripheral blood vessels including those of the retina which may leak fluid, blood and occasionally fats into the retina causing it to swell. *Age-related macular degeneration may cause macular edema. As individuals age there may be a natural deterioration in the macula which can lead to the depositing of drusen under the retina sometimes with the formation of abnormal blood vess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Route Of Administration
In pharmacology and toxicology, a route of administration is the way by which a medication, drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. Common examples include oral administration, oral and intravenous therapy, intravenous administration. Routes can also be classified based on where the target of action is. Action may be topical medication, topical (local), enteral administration, enteral (system-wide effect, but delivered through the gastrointestinal tract), or #Parenteral, parenteral (systemic action, but is delivered by routes other than the GI tract). Route of administration and dosage form are aspects of drug delivery. Classification Routes of administration are usually classified by application location (or exposition). The route or course the active substance takes from application location to the location where it has its target effect is usually rat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
