|
White Dot Syndromes
White dot syndromes are inflammatory diseases characterized by the presence of white dots on the fundus, the interior surface of the eye. Tewari A, Elliot D. White Dot Syndromes. 2007. Emedicine from WebMD. 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.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. There are many theories for the etiology of white dot syndromes including infectious, viral, genetics and autoimmune. Classically recognized white dot syndromes include:Forrester JV, IOIS, Okada AA, BenEzra D. Posterior segment intraocular inflammation: guidelines. 1998:184. * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fundus (eye)
The fundus of the eye is the interior surface of the eye opposite the lens and includes the retina, optic disc, macula, fovea, and posterior pole.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. The fundus can be examined by ophthalmoscopy and/or fundus photography. Variation The color of the fundus varies both between and within species. In one study of primates the retina is blue, green, yellow, orange, and red; only the human fundus (from a lightly pigmented blond person) is red. The major differences noted among the "higher" primate species were size and regularity of the border of macular area, size and shape of the optic disc, apparent 'texturing' of retina, and pigmentation of retina. Clinical significance Medical signs that can be detected from observation of eye fundus (generally by funduscopy) include hemorrhages, exudates, cotton wool spots, blood vessel abnormalities ( tortuosity, puls ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choroid
The choroid, also known as the choroidea or choroid coat, is a part of the uvea, the vascular layer of the eye. It contains connective tissues, and lies between the retina and the sclera. The human choroid is thickest at the far extreme rear of the eye (at 0.2 mm), while in the outlying areas it narrows to 0.1 mm. The choroid provides oxygen and nourishment to the outer layers of the retina. Along with the ciliary body and iris, the choroid forms the uveal tract. The structure of the choroid is generally divided into four layers (classified in order of furthest away from the retina to closest): *Haller's layer – outermost layer of the choroid consisting of larger diameter blood vessels; * Sattler's layer – layer of medium diameter blood vessels; * Choriocapillaris – layer of capillaries; and * Bruch's membrane (synonyms: Lamina basalis, Complexus basalis, Lamina vitra) – innermost layer of the choroid. Blood supply There are two circulations of the eye: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinal Pigment Epithelium
The pigmented layer of retina or retinal pigment epithelium (RPE) is the pigment A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored sub ...ed 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. History 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. Anatomy The RPE is composed of a single layer of hexagonal cells that are densely packed with pigment granules. When viewed from the outer surface, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retina
The retina (; or retinas) is the innermost, photosensitivity, light-sensitive layer of tissue (biology), tissue of the eye of most vertebrates and some Mollusca, molluscs. The optics of the eye create a focus (optics), 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 photographic film, film or image sensor in a camera. The neural retina consists of several layers of neurons interconnected by Chemical synapse, synapses and is supported by an outer layer of pigmented epithelial cells. The primary light-sensing cells in the retina are the photoreceptor cells, which are of two types: rod cell, rods and cone cell, cones. Rods function mainly in dim light and provide monochromatic vision. Cones function in well-lit conditions and are responsible fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmology
Ophthalmology (, ) is the branch of medicine that deals with the diagnosis, treatment, and surgery of eye diseases and disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a medical degree, a doctor specialising in ophthalmology must pursue additional postgraduate residency training specific to that field. In the United States, following graduation from medical school, one must complete a four-year residency in ophthalmology to become an ophthalmologist. Following residency, additional specialty training (or fellowship) may be sought in a particular aspect of eye pathology. Ophthalmologists prescribe medications to treat ailments, such as eye diseases, implement laser therapy, and perform surgery when needed. Ophthalmologists provide both primary and specialty eye care—medical and surgical. Most ophthalmologists participate in academic research on eye diseases at some point in their training and many inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RLBP1
Retinaldehyde-binding protein 1 (RLBP1) also known as cellular retinaldehyde-binding protein (CRALBP) is a 36-kD water-soluble protein that in humans is encoded by the ''RLBP1'' gene. Discovery Cellular retinol binding protein (CRBP) was first discovered in 1973 from lung tissues by Bashor et al. There have been three cellular retinol binding protein categories discovered; Cellular retinol-binding protein, cellular retinoic acid-binding protein and cellular retinaldehyde-binding protein(CRALBP). CRALBP was first discovered in 1977, after it was purified from retina and retinal pigment epithelial cells. Function The cellular retinaldehyde-binding protein transports 11-cis-retinal (also known as 11-cis-retinaldehyde) as its physiological ligands. It plays a critical role as an 11-cis-retinal acceptor which facilitates the enzymatic isomerization of all 11-trans-retinal to 11-cis-retinal, in the isomerization of the rod and cones of the visual cycle. Tissue distribution CR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Idiopathic Blind Spot Enlargement Syndrome
Acute idiopathic blind spot enlargement syndrome (AIBSE) is a rare eye disease affecting the retina of the eye. It is basically a type of retinopathy which affects females more than males. Currently there is no treatment for this condition, but, it is usually self limiting. Cause Though exact etiology of AIBSE syndrome is unknown, studies shows that viral illness like influenza and vaccinations like MMR may trigger the condition. Demographics AIBSE syndrome affects females more than males. Higher incidence is seen in Caucasian people. Signs and Symptoms Enlargement of blind spot area in the visual field of the eye is the main sign and acute onset photopsia is the main symptom of AIBSE syndrome. Other symptoms include monocular scotoma and reduced light perception. Diagnosis Diagnostic techniques like ophthalmoscopy, visual field test, optical coherence tomography, fluorescein angiography, multifocal electroretinography and electrophysiology may be used in diagnosing AIBSE syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophages
Macrophages (; abbreviated MPhi, φ, MΦ or MP) are a type of white blood cell of the innate immune system that engulf and digest pathogens, such as cancer cells, microbes, cellular debris and foreign substances, which do not have proteins that are specific to healthy body cells on their surface. This self-protection method can be contrasted with that employed by Natural killer cell, Natural Killer cells. This process of engulfment and digestion is called phagocytosis; it acts to defend the host against infection and injury. Macrophages are found in essentially all tissues, where they patrol for potential pathogens by amoeboid movement. They take various forms (with various names) throughout the body (e.g., histiocytes, Kupffer cells, alveolar macrophages, microglia, and others), but all are part of the mononuclear phagocyte system. Besides phagocytosis, they play a critical role in nonspecific defense (innate immunity) and also help initiate specific defense mechanisms (adapti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocytes
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include T cells (for cell-mediated and cytotoxic adaptive immunity), B cells (for humoral, antibody-driven adaptive immunity), and innate lymphoid cells (ILCs; "innate T cell-like" cells involved in mucosal immunity and homeostasis), of which natural killer cells are an important subtype (which functions in cell-mediated, cytotoxic innate immunity). They are the main type of cell found in lymph, which prompted the name "lymphocyte" (with ''cyte'' meaning cell). Lymphocytes make up between 18% and 42% of circulating white blood cells. Types The three major types of lymphocyte are T cells, B cells and natural killer (NK) cells. They can also be classified as small lymphocytes and large lymphocytes based on their size and appearance. Lymphocytes can be identified by their large nucleus. T cells and B cells T cells (thymus cells) and B cells ( bone marrow- or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granuloma
A granuloma is an aggregation of macrophages (along with other cells) that forms in response to chronic inflammation. This occurs when the immune system attempts to isolate foreign substances that it is otherwise unable to eliminate. Such substances include infectious organisms including bacteria and fungi, as well as other materials such as foreign objects, keratin, and suture fragments. Definition In pathology, a granuloma is an organized collection of macrophages. In medical practice, doctors occasionally use the term ''granuloma'' in its more literal meaning: "a small nodule". Since a small nodule can represent any tissue from a harmless nevus to a malignant tumor, this use of the term is not very specific. Examples of this use of the term ''granuloma'' are the lesions known as vocal cord granuloma (known as contact granuloma), pyogenic granuloma, and intubation granuloma, all of which are examples of granulation tissue, not granulomas. "Pulmonary hyalinizing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Pole
In ophthalmology, the posterior pole is the back of the eye, usually referring to the retina between the optic disc and the macula.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. See also * Fundus (eye) The fundus of the eye is the interior surface of the eye opposite the lens and includes the retina, optic disc, macula, fovea, and posterior pole.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Pu ... References Human eye anatomy {{eye-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Posterior Multifocal Placoid Pigment Epitheliopathy
Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is an acquired inflammatory uveitis that belongs to the heterogenous group of white dot syndromes in which light-coloured (yellowish-white) lesions form in the retina. Early in the course of the disease, the lesions cause acute and marked vision loss (if it interferes with the optic nerve) that ranges from mild to severe but is usually transient in nature. APMPPE is classified as an inflammatory disorder that is usually bilateral and acute in onset but self-limiting. The lesions leave behind some pigmentation, but visual acuity eventually improves even without any treatment (providing scarring doesn't interfere with the optic nerve). It occurs equally between men and women with a male to female ratio of 1.2:1. Mean onset age is 27, but has been seen in people aged 16 to 40. It is known to occur after or concurrently with a systemic infection (but not always), showing that it is related generally to an altered immun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
