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Intraocular Hemorrhage
Intraocular hemorrhage (sometimes called hemophthalmos or hemophthalmia) is bleeding inside the eye (''oculus'' in Latin). Bleeding can occur from any structure of the eye where there is vasculature or blood flow, including the anterior chamber, vitreous cavity, retina, choroid, suprachoroidal space, or optic disc. Intraocular hemorrhage may be caused by physical trauma (direct injury to the eye); ocular surgery (such as to repair cataracts); or other diseases, injuries, or disorders (such as diabetes, hypertension, or shaken baby syndrome). Severe bleeding may cause high pressure inside the eye, leading to blindness. Types Intraocular hemorrhage is classified based on the location of the bleeding: * Hyphema (in the anterior chamber) * Suprachoroidal hemorrhage (SCH) is a rare complication of intraocular surgery in which blood from the ciliary arteries enters the space between the choroid and the sclera. It is potentially vision-threatening. *In the posterior segment of the eye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bleeding
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties (by comparison, blood donation typically takes 8–10% of the donor's blood volume). The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery. Types * Upper head ** Intracranial hemorrhage – bleeding in the skull. ** Cerebral hemorrhage – a type of intracranial hemorrhage, bleeding within the brain tissue itself. ** Intracerebral hemorrhage – bleeding in the brain caused by the ruptur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciliary Arteries
The ciliary arteries are divisible into three groups, the long posterior, short posterior, and the anterior. * The short posterior ciliary arteries from six to twelve in number, arise from the ophthalmic artery as it crosses the optic nerve. * The long posterior ciliary arteries, two for each eye, pierce the posterior part of the sclera at some little distance from the optic nerve. * The anterior ciliary arteries The anterior ciliary arteries are seven small arteries in each eye-socket that supply the conjunctiva, sclera and the recti muscles. They are derived from the muscular branches of the ophthalmic artery. Course The anterior ciliary arteries are ... are derived from the muscular branches of the ophthalmic artery. Additional images File:Gray514.png, The ophthalmic artery and its branches File:Gray878.png, Iris, front view. File:Gray880.png, The terminal portion of the optic nerve and its entrance into the eyeball, in horizontal section. References Arteries of ... [...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 force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Vessel
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues. Blood vessels are needed to sustain life, because all of the body's tissues rely on their functionality. There are five types of blood vessels: the arteries, which carry the blood away from the heart; the arterioles; the capillaries, where the exchange of water and chemicals between the blood and the tissues occurs; the venules; and the veins, which carry blood from the capillaries back towards the heart. The word ''vascular'', meaning relating to the blood vessels, is derived from the Latin ''vas'', meaning vessel. Some structures – such as cartilage, the epithelium, and the lens and cornea of the eye – do not contain blood vessels and are labeled ''avascular''. Etymology * artery: late Middle English; from Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cough
A cough is a sudden expulsion of air through the large breathing passages that can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phases: an inhalation, a forced exhalation against a closed glottis, and a violent release of air from the lungs following opening of the glottis, usually accompanied by a distinctive sound. Frequent coughing usually indicates the presence of a disease. Many viruses and bacteria benefit, from an evolutionary perspective, by causing the host to cough, which helps to spread the disease to new hosts. Most of the time, irregular coughing is caused by a respiratory tract infection but can also be triggered by choking, smoking, air pollution, asthma, gastroesophageal reflux disease, post-nasal drip, chronic bronchitis, lung tumors, heart failure and medications such as angiotensin-converting-enzyme inhibitors (ACE inhibitors). Treatment should t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sneeze
A sneeze (also known as sternutation) is a semi-autonomous, convulsive expulsion of air from the lungs through the nose and mouth, usually caused by foreign particles irritating the nasal mucosa. A sneeze expels air forcibly from the mouth and nose in an explosive, spasmodic involuntary action. This action allows for mucus to escape through the nasal cavity. Sneezing is possibly linked to sudden exposure to bright light, sudden change (fall) in temperature, breeze of cold air, a particularly full stomach, exposure to allergens, or viral infection. Because sneezes can spread disease through infectious aerosol droplets, it is recommended to cover one's mouth and nose with the forearm, the inside of the elbow, a tissue or a handkerchief while sneezing. In addition to covering the mouth, looking down is also recommended in order to change the direction of the droplets spread and avoid high concentration in the human breathing heights. The function of sneezing is to expel mucus con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunctiva
The conjunctiva is a thin mucous membrane that lines the inside of the eyelids and covers the sclera (the white of the eye). It is composed of non-keratinized, stratified squamous epithelium with goblet cells, stratified columnar epithelium and stratified cuboidal epithelium (depending on the zone). The conjunctiva is highly vascularised, with many microvessels easily accessible for imaging studies. Structure The conjunctiva is typically divided into three parts: Blood supply Blood to the bulbar conjunctiva is primarily derived from the ophthalmic artery. The blood supply to the palpebral conjunctiva (the eyelid) is derived from the external carotid artery. However, the circulations of the bulbar conjunctiva and palpebral conjunctiva are linked, so both bulbar conjunctival and palpebral conjunctival vessels are supplied by both the ophthalmic artery and the external carotid artery, to varying extents. Nerve supply Sensory innervation of the conjunctiva is divided into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subconjunctival Hemorrhage
Subconjunctival bleeding, also known as subconjunctival hemorrhage or subconjunctival haemorrhage, is bleeding from a small blood vessel over the whites of the eye. It results in a red spot in the white of the eye. There is generally little to no pain and vision is not affected. Generally only one eye is affected. Natural causes can include coughing, vomiting, heavy lifting, straining to pass hard stools during acute constipation or the act of "pushing" or "bearing down" during labour/childbirth as these activities can increase the blood pressure in the vascular systems supplying the retina. There are up to four vascular retinal plexuses that are supplied by tiny, delicate capillaries whose walls if encountered with a sudden amount of force from blood will rupture. External causes can include direct impact/injury from an accidental bump or a physical altercation resulting in blunt force trauma. Risk factors include hypertension, diabetes, old age, and blood thinners. They occur i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macula
The macula (/ˈmakjʊlə/) or macula lutea is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around and is subdivided into the umbo, foveola, foveal avascular zone, fovea, parafovea, and perifovea areas. The anatomical macula at a size of is much larger than the clinical macula which, at a size of , corresponds to the anatomical fovea. The macula is responsible for the central, high-resolution, color vision that is possible in good light; and this kind of vision is impaired if the macula is damaged, for example in macular degeneration. The clinical macula is seen when viewed from the pupil, as in ophthalmoscopy or retinal photography. The term macula lutea comes from Latin ''macula'', "spot", and ''lutea'', "yellow". Structure The macula is an oval-shaped pigmented area in the center of the retina of the human eye and other animal eyes. Its center is shifted slightly away from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitreous Humour
The vitreous body (''vitreous'' meaning "glass-like"; , ) is the clear gel that fills the space between the lens and the retina of the eyeball (the vitreous chamber) in humans and other vertebrates. It is often referred to as the vitreous humor (also spelled humour, from Latin meaning liquid) or simply "the vitreous". Vitreous fluid or "liquid vitreous" is the liquid component of the vitreous gel, found after a vitreous detachment. It is not to be confused with the aqueous humor, the other fluid in the eye that is found between the cornea and lens. Structure The vitreous humor is a transparent, colorless, gelatinous mass that fills the space in the eye between the lens and the retina. It is surrounded by a layer of collagen called the vitreous membrane (or hyaloid membrane or vitreous cortex) separating it from the rest of the eye. It makes up four-fifths of the volume of the eyeball. The vitreous humour is fluid-like near the centre, and gel-like near the edges. The vitreous h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
