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Schlemm's Canal
Schlemm's canal, also known as the canal of Schlemm, and as the scleral venous sinus, is a circular Lymph, lymphatic-like vessel in the human eye, eye. It collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels. Canaloplasty may be used to widen it. Structure Schlemm's canal is an endothelium-lined tube, resembling that of a lymphatic vessel. On the inside of the canal, nearest to the aqueous humor, it is covered and held open by the trabecular meshwork. This creates outflow resistance against the Aqueous humour, aqueous humor. Development While Schlemm's canal has generally been considered as a vein or a scleral venous sinus, the canal is similar to the lymphatic system, lymphatic vasculature. It is never filled with blood in physiological settings as it does not receive arterial blood circulation. Schlemm's canal displays several features of lymphatic endothelium, including the expression of PROX1, VEGFR3, CCL21, FOXC2, but lacked th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Eye
The human eye is a sensory organ in the visual system that reacts to light, visible light allowing eyesight. Other functions include maintaining the circadian rhythm, and Balance (ability), keeping balance. The eye can be considered as a living optics, optical device. It is approximately spherical in shape, with its outer layers, such as the outermost, white part of the eye (the sclera) and one of its inner layers (the pigmented choroid) keeping the eye essentially stray light, light tight except on the eye's optic axis. In order, along the optic axis, the optical components consist of a first lens (the cornea, cornea—the clear part of the eye) that accounts for most of the optical power of the eye and accomplishes most of the Focus (optics), focusing of light from the outside world; then an aperture (the pupil) in a Diaphragm (optics), diaphragm (the Iris (anatomy), iris—the coloured part of the eye) that controls the amount of light entering the interior of the eye; then an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiopoietin 2
Angiopoietin-2 is a protein that in humans is encoded by the ''ANGPT2'' gene. Naturally occurring antagonist for both ANGPT1 and TIE2; expressed only at the sites of vascular remodeling; similar to angiopoietin-1 Function * See Angiopoietin#Clinical relevance Interactions ANGPT2 has been shown to interact with TEK tyrosine kinase. See also * Angiopoietin Angiopoietin is part of a family of vascular growth factors that play a role in embryonic and postnatal angiogenesis. Angiopoietin signaling most directly corresponds with angiogenesis, the process by which new arteries and veins form from pree ... References External links * Further reading * * * * * * * * * * * * * * * * {{gene-8-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intraocular Pressure
Intraocular pressure (IOP) is the fluid pressure inside the eye. Tonometry is the method eye care professionals use to determine this. IOP is an important aspect in the evaluation of patients at risk of glaucoma. Most tonometers are calibrated to measure pressure in millimeters of mercury (mmHg). Physiology Intraocular pressure is determined by the production and drainage of aqueous humour by the ciliary body and its drainage via the trabecular meshwork and uveoscleral outflow. The reason for this is because the vitreous humour in the posterior segment has a relatively fixed volume and thus does not affect intraocular pressure regulation. An important quantitative relationship (Goldmann's equation) is as follows: :P_o = \frac + P_v Where: * P_o is the IOP in millimeters of mercury (mmHg) * F the rate of aqueous humour formation in microliters per minute (μL/min) * U the resorption of aqueous humour through the uveoscleral route (μL/min) * C is the facility of outflow in mic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomist
Anatomy () is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine, and is often studied alongside physiology. Anatomy is a complex and dynamic field that is constantly evolving as discoveries are made. In recent years, there has been a significant increase in the use of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germans
Germans (, ) are the natives or inhabitants of Germany, or sometimes more broadly any people who are of German descent or native speakers of the German language. The Basic Law for the Federal Republic of Germany, constitution of Germany, implemented in 1949 following the end of World War II, defines a German as a German nationality law, German citizen. During the 19th and much of the 20th century, discussions on German identity were dominated by concepts of a common language, culture, descent, and history.. "German identity developed through a long historical process that led, in the late 19th and early 20th centuries, to the definition of the German nation as both a community of descent (Volksgemeinschaft) and shared culture and experience. Today, the German language is the primary though not exclusive criterion of German identity." Today, the German language is widely seen as the primary, though not exclusive, criterion of German identity. Estimates on the total number of Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Schlemm
Friedrich Schlemm (11 December 1795 – 27 May 1858) was a German anatomist who was professor at the University of Berlin. He was born in Salzgitter. As his family could not afford higher education, he was apprenticed to a barber-surgeon in Braunschweig. This gave him the opportunity to study anatomy and surgery at the local Anatomico-Surgical Institute. In 1821 he received his medical doctorate from the University of Berlin, and became Prosector at the university in 1823. In 1829 he became "professor extraordinary" of anatomy, and attained the title of "full professor" in 1833. Recently discovered archival sources demonstrate that, in June 1816, Schlemm and a fellow student disinterred the body of a deceased woman late at night in a Braunschweig churchyard to bring the body to this Institute and study the effects of rickets on the woman's bones. They were caught and sentenced to 4 weeks of prison. Subsequently, Schlemm left Braunschweig and found work as a low-rank army surgeon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaucoma
Glaucoma is a group of eye diseases that can lead to damage of the optic nerve. The optic nerve transmits visual information from the eye to the brain. Glaucoma may cause vision loss if left untreated. It has been called the "silent thief of sight" because the loss of vision usually occurs slowly over a long period of time. A major risk factor for glaucoma is increased pressure within the eye, known as Intraocular pressure, intraocular pressure (IOP). It is associated with old age, a family history of glaucoma, and certain medical conditions or the use of some medications. The word ''glaucoma'' comes from the Ancient Greek word (), meaning 'gleaming, blue-green, gray'. Of the different types of glaucoma, the most common are called open-angle glaucoma and closed-angle glaucoma. Inside the eye, a liquid called Aqueous humour, aqueous humor helps to maintain shape and provides nutrients. The aqueous humor normally drains through the trabecular meshwork. In open-angle glaucoma, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buphthalmos
Buphthalmos (plural: buphthalmoses) is enlargement of the eyeball and is most commonly seen in infants and young children. It is sometimes referred to as buphthalmia (plural buphthalmias). It usually appears in the newborn period or the first 3 months of life. and in most cases indicates the presence of congenital (infantile) glaucoma, which is a disorder in which elevated pressures within the eye lead to structural eye damage and vision loss. Signs and symptoms Buphthalmos in itself is merely a clinical sign and does not generate symptoms. Patients with glaucoma often initially have no symptoms; later, they can exhibit excessive tearing (lacrimation) and extreme sensitivity to light (photophobia). On ophthalmologic exam, a doctor can detect increased intraocular pressure, distortion of the optic disc, and corneal edema, which manifests as haziness. Other symptoms include a prominent eyeball, Haab's striae tear in the Descemet's membrane of the cornea, an enlarged cornea, and my ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanocyte
Melanocytes are melanin-producing neural-crest, neural crest-derived cell (biology), cells located in the bottom layer (the stratum basale) of the skin's epidermis (skin), epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and heart found in many mammals and birds. Melanin is a dark pigment primarily responsible for skin color. Once synthesized, melanin is contained in special organelles called melanosomes which can be transported to nearby keratinocytes to induce pigmentation. Thus darker skin tones have more melanosomes present than lighter skin tones. Functionally, melanin serves as protection against Ultraviolet, UV radiation. Melanocytes also have a role in the immune system. Function Through a process called melanogenesis, melanocytes produce melanin, which is a pigment found in the human skin, skin, human eye, eyes, hair, nasal cavity, and inner ear. This melanogenesis leads to a long-lasting pigmentation, which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is coherence (physics), ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and Photolithography#Light sources, lithography. It also allows a laser beam to stay narrow over great distances (collimated light, collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argon Laser
An ion laser is a gas laser that uses an ionized gas as its lasing medium. Like other gas lasers, ion lasers feature a sealed cavity containing the laser medium and mirrors forming a Fabry–Pérot resonator. Unlike helium–neon lasers, the energy level transitions that contribute to laser action come from ions. Because of the large amount of energy required to excite the ionic transitions used in ion lasers, the required current is much greater, and as a result almost all except for the smallest ion lasers are water-cooled. A small air-cooled ion laser might produce, for example, 130 milliwatts of output light with a tube current of about 10 amperes and a voltage of 105 volts. Since one ampere times one volt is one watt, this is an electrical power input of about one kilowatt. Subtracting the (desirable) light output of 130 mW from power input, this leaves the large amount of waste heat of nearly one kW. This has to be dissipated by the cooling system. In other words, the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Trabeculoplasty
Trabeculoplasty is a laser treatment for glaucoma. It is done on an argon laser equipped slit lamp, using a Goldmann gonioscope lens mirror. Specifically, an argon laser is used to improve drainage through the eye's trabecular meshwork, from which the aqueous humour drains. This helps reduce intraocular pressure caused by open-angle glaucoma. Research The LiGHT trial compared the effectiveness of eye drops and selective laser trabeculoplasty for open angle glaucoma. Both contributed to a similar quality of life but most people undergoing laser treatment were able to stop using eye drops. Laser trabeculoplasty was also shown to be more cost-effective.; See also * Eye surgery * Laser surgery * Trabeculectomy Trabeculectomy is a surgical procedure used in the treatment of glaucoma to relieve intraocular pressure by removing part of the eye's trabecular meshwork and adjacent structures. It is the most common glaucoma surgery performed and allows drainag ... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
