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Vitreous Base
The vitreous base is an area in the fundus of the eye in which the vitreous membrane, neural retina, and pigment epithelium all are firmly adherent, one to the other. The vitreous membrane is more firmly attached to the retina The retina (from la, rete "net") 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 ... anteriorly at the vitreous base. The vitreous membrane does not normally detach from the vitreous base, although it can be detached with extreme trauma. Vitreous base detachment is typically associated with blunt ocular trauma.Myron Yanoff; Jay S Duker; James J Augsburger; et al: ''Ophthalmology'', 3rd ed. References {{reflist Human eye anatomy ... [...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, pulsation an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitreous Membrane
The vitreous membrane (or hyaloid membrane or vitreous cortex) is a layer of collagen separating the vitreous humour from the rest of the eye. At least two parts have been identified anatomically. The posterior hyaloid membrane separates the rear of the vitreous from the retina. It is a false anatomical membrane. The anterior hyaloid membrane separates the front of the vitreous from the lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'' .... Andres Bernal, Jean-Marie Parel, Fabrice MannsEvidence for posterior zonular fiber attachment on the anterior hyaloid membrane "Investigative Ophthalmology and Visual Science" 2006, 47, 4708-4713. Bernal et al. describe it "as a delicate structure in the form of a thin layer that runs from the pars plana to the posterior lens, where it shares ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigment Epithelium
The 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. 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, these cells are smooth and hexagonal in shape. When seen in section, each cell consists of an outer non-pigmented part containing a large oval nucleus and an inner pigmented portion which extends as a series of straight thread-like processes between the rods, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retina
The retina (from la, rete "net") 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 image sensor in a camera. The neural retina consists of several layers of neurons interconnected by 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: rods and cones. Rods function mainly in dim light and provide monochromatic vision. Cones function in well-lit conditions and are responsible for the perception of colour through the use of a range of opsins, as well as high-acuity vision used f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blunt Trauma
Blunt trauma, also known as blunt force trauma or non-penetrating trauma, is physical traumas, and particularly in the elderly who fall. It is contrasted with penetrating trauma which occurs when an object pierces the skin and enters a tissue of the body, creating an open wound and bruise. Blunt trauma can result in contusions, abrasions, lacerations, internal hemorrhages, bone fractures, as well as death. Blunt trauma represents a significant cause of disability and death in people under the age of 35 years worldwide. Classification Blunt abdominal trauma Blunt abdominal trauma (BAT) represents 75% of all blunt trauma and is the most common example of this injury. 75% of BAT occurs in motor vehicle crashes, in which rapid deceleration may propel the driver into the steering wheel, dashboard, or seatbelt, causing contusions in less serious cases, or rupture of internal organs from briefly increased intraluminal pressure in the more serious, depending on the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
