Macular degenerationMacular degeneration, also known as age-related macular degeneration (AMD or ARMD), is a medical condition which may result in blurred or no vision in the center of the visual field. Early on there are often no symptoms. Over time, however, some people experience a gradual worsening of vision that may affect one or both eyes. While it does not result in complete blindness, loss of central vision can make it hard to recognize faces, drive, read, or perform other activities of daily life. Visual hallucinations may also occur.
Fundus photographyFundus photography involves photographing the rear of an eye, also known as the fundus. Specialized fundus cameras consisting of an intricate microscope attached to a flash enabled camera are used in fundus photography. The main structures that can be visualized on a fundus photo are the central and peripheral retina, optic disc and macula. Fundus photography can be performed with colored filters, or with specialized dyes including fluorescein and indocyanine green.
TherapyA therapy or medical treatment (Both words, "Treatment" and "Therapy" are often abbreviated tx, Tx, or Tx) is the attempted remediation of a health problem, usually following a medical diagnosis. As a rule, each therapy has indications and contraindications. There are many different types of therapy. Not all therapies are effective. Many therapies can produce unwanted adverse effects. Medical treatment and therapy are generally considered synonyms. However, in the context of mental health, the term therapy may refer specifically to psychotherapy.
RetinaThe retina (from rete "net"; : retinae or retinas) is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then processes that image within the retina and sends nerve impulses along the optic nerve to the visual cortex to create visual perception. The retina serves a function which is in many ways analogous to that of the film or in a camera.
Retinal detachmentRetinal 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. The retina is a thin layer of light-sensitive tissue on the back wall of the eye. The optical system of the eye focuses light on the retina much like light is focused on the film in a camera.
Fluorescein angiographyFluorescein angiography (FA), fluorescent angiography (FAG), or fundus fluorescein angiography (FFA) is a technique for examining the circulation of the retina and choroid (parts of the fundus) using a fluorescent dye and a specialized camera. Sodium fluorescein is added into the systemic circulation, the retina is illuminated with blue light at a wavelength of 490 nanometers, and an angiogram is obtained by photographing the fluorescent green light that is emitted by the dye.
Expressive therapiesThe expressive therapies are the use of the creative arts as a form of therapy, including the distinct disciplines expressive arts therapy and the creative arts therapies (art therapy, dance/movement therapy, drama therapy, music therapy, writing therapy, poetry therapy, and psychodrama). The expressive therapies are based on the assumption that people can heal through the various forms of creative expression. Expressive therapists share the belief that through creative expression and the tapping of the imagination, people can examine their body, feelings, emotions, and thought process.
Vascular endothelial growth factorVascular endothelial growth factor (VEGF, vɛdʒ'ɛf), originally known as vascular permeability factor (VPF), is a signal protein produced by many cells that stimulates the formation of blood vessels. To be specific, VEGF is a sub-family of growth factors, the platelet-derived growth factor family of cystine-knot growth factors. They are important signaling proteins involved in both vasculogenesis (the de novo formation of the embryonic circulatory system) and angiogenesis (the growth of blood vessels from pre-existing vasculature).
Retinal pigment epitheliumThe pigmented layer of retina or retinal pigment epithelium (RPE) is the pigmented cell layer just outside the neurosensory retina that nourishes retinal visual cells, and is firmly attached to the underlying choroid and overlying retinal visual cells. The RPE was known in the 18th and 19th centuries as the pigmentum nigrum, referring to the observation that the RPE is dark (black in many animals, brown in humans); and as the tapetum nigrum, referring to the observation that in animals with a tapetum lucidum, in the region of the tapetum lucidum the RPE is not pigmented.
AngiogenesisAngiogenesis is the physiological process through which new blood vessels form from pre-existing vessels, formed in the earlier stage of vasculogenesis. Angiogenesis continues the growth of the vasculature mainly by processes of sprouting and splitting, but processes such as coalescent angiogenesis, vessel elongation and vessel cooption also play a role. Vasculogenesis is the embryonic formation of endothelial cells from mesoderm cell precursors, and from neovascularization, although discussions are not always precise (especially in older texts).
Light therapyLight therapy, also called phototherapy or bright light therapy is the exposure to direct sunlight or artificial light at controlled wavelengths in order to treat a variety of medical disorders, including seasonal affective disorder (SAD), circadian rhythm sleep-wake disorders, cancers, and skin wound infections. Treating skin conditions such as neurodermatitis, psoriasis, acne vulgaris, and eczema with ultraviolet light is called ultraviolet light therapy.
Biological pigmentBiological pigments, also known simply as pigments or biochromes, are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments. Many biological structures, such as skin, eyes, feathers, fur and hair contain pigments such as melanin in specialized cells called chromatophores. In some species, pigments accrue over very long periods during an individual's lifespan.
Alternative cancer treatmentsAlternative cancer treatment describes any cancer treatment or practice that is not part of the conventional standard of cancer care. These include special diets and exercises, chemicals, herbs, devices, and manual procedures. Most alternative cancer treatments do not have high-quality evidence supporting their use and many have been described as fundamentally pseudoscientific. Concerns have been raised about the safety of some purported treatments and some have been found unsafe in clinical trials.
Photodynamic therapyPhotodynamic therapy (PDT) is a form of phototherapy involving light and a photosensitizing chemical substance, used in conjunction with molecular oxygen to elicit cell death (phototoxicity). PDT is popularly used in treating acne. It is used clinically to treat a wide range of medical conditions, including wet age-related macular degeneration, psoriasis, atherosclerosis and has shown some efficacy in anti-viral treatments, including herpes. It also treats malignant cancers including head and neck, lung, bladder and particular skin.
Alternative medicineAlternative medicine is any practice that aims to achieve the healing effects of medicine despite lacking biological plausibility, testability, repeatability or evidence of effectiveness. Unlike modern medicine, which employs the scientific method to test plausible therapies by way of responsible and ethical clinical trials, producing repeatable evidence of either effect or of no effect, alternative therapies reside outside of medical science and do not originate from using the scientific method, but instead rely on testimonials, anecdotes, religion, tradition, superstition, belief in supernatural "energies", pseudoscience, errors in reasoning, propaganda, fraud, or other unscientific sources.
FractionA fraction (from fractus, "broken") represents a part of a whole or, more generally, any number of equal parts. When spoken in everyday English, a fraction describes how many parts of a certain size there are, for example, one-half, eight-fifths, three-quarters. A common, vulgar, or simple fraction (examples: and ) consists of an integer numerator, displayed above a line (or before a slash like ), and a non-zero integer denominator, displayed below (or after) that line.
Cognitive behavioral therapyCognitive behavioral therapy (CBT) is a psycho-social intervention that aims to reduce symptoms of various mental health conditions, primarily depression and anxiety disorders. Cognitive behavioral therapy is one of the most effective means of treatment for substance abuse and co-occurring mental health disorders. CBT focuses on challenging and changing cognitive distortions (such as thoughts, beliefs, and attitudes) and their associated behaviors to improve emotional regulation and develop personal coping strategies that target solving current problems.
Amsler gridThe Amsler grid, used since 1945, is a grid of horizontal and vertical lines used to monitor a person's central visual field. The grid was developed by Marc Amsler, a Swiss ophthalmologist. It is a diagnostic tool that aids in the detection of visual disturbances caused by changes in the retina, particularly the macula (e.g. macular degeneration, Epiretinal membrane), as well as the optic nerve and the visual pathway to the brain. Amsler grid usually help detecting defects in central 20 degrees of the visual field.
NeovascularizationNeovascularization is the natural formation of new blood vessels (neo- + vascular + -ization), usually in the form of functional microvascular networks, capable of perfusion by red blood cells, that form to serve as collateral circulation in response to local poor perfusion or ischemia. Growth factors that inhibit neovascularization include those that affect endothelial cell division and differentiation.
Photothermal therapyPhotothermal therapy (PTT) refers to efforts to use electromagnetic radiation (most often in infrared wavelengths) for the treatment of various medical conditions, including cancer. This approach is an extension of photodynamic therapy, in which a photosensitizer is excited with specific band light. This activation brings the sensitizer to an excited state where it then releases vibrational energy (heat), which is what kills the targeted cells. Unlike photodynamic therapy, photothermal therapy does not require oxygen to interact with the target cells or tissues.
