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The cornea occupies the front center part of the outer wall of the eye. It is made of collagen fibers in a very special arrangement so that the cornea is clear. One looks through the cornea to see the iris and pupil. The cornea bends light coming into the eye so that it is focused on the retina.
Traumatic brain injury (TBI) is a nondegenerative, noncongenital insult to the brain from an external mechanical force, possibly leading to permanent or temporary impairment of cognitive, physical, and psychosocial functions, with an associated diminished or altered state of consciousness.
Most people have general anesthesia right before surgery. This means you will be asleep and pain-free. Other kinds of anesthesia, like regional anesthesia or a block, may also be used for this surgery. The tissue to replace your damaged ACL will come from your own body or from a donor. A donor is a person who has died and chose to give all or part of his or her body to help others. Tissue taken from your own body is called an autograft. The two most common places to take tissue from are the knee cap tendon or the hamstring tendon. Your hamstring is the muscle behind your knee. Tissue taken from a donor is called an allograft. The procedure is usually performed with the help of knee arthroscopy. With arthroscopy, a tiny camera is inserted into the knee through a small surgical cut. The camera is connected to a video monitor in the operating room. Your surgeon will use the camera to check the ligaments and other tissues of your knee. Your surgeon will make other small cuts around your knee and insert other medical instruments. Your surgeon will fix any other damage found, and then will replace your ACL by following these steps: The torn ligament will be removed with a shaver or other instruments. If your own tissue is being used to make your new ACL, your surgeon will make a larger cut. Then, the autograft will be removed through this cut. Your surgeon will make tunnels in your bone to bring the new tissue through. This new tissue will be in the same place as your old ACL. Your surgeon will attach the new ligament to the bone with screws or other devices to hold it in place. As it heals, the bone tunnels fill in. This holds the new ligament in place. At the end of the surgery, your surgeon will close your cuts with sutures (stitches) and cover the area with a dressing. You may be able to view pictures after the procedure of what the doctor saw and what was done during the surgery.
The eyes A close up of a young person's eyes. The eyes are responsible for four-fifths of all the information our brain receives. Here you can find out a bit more about how they work, common problems that affect vision and the work Sightsavers does to treat and prevent avoidable blindness. You can also find out more about the people whose lives have been changed thanks to donations from people like you. How do eyes work? (click image to see enlarged version or click here for text alternative) Graphic of an eye with information about its different parts The images we see are made up of light reflected from the objects we look at. This light enters the eye through the cornea. Because this part of the eye is curved, it bends the light, creating an upside down image on the retina (this is eventually put the right way up by the brain). The retina is a complex part of the eye, but only the very back of it is light sensitive. This part of the retina has roughly the area of a 10p coin, and is packed with photosensitive cells called rods and cones. Cones are the cells responsible for daylight vision. There are three kinds – each responding to a different wavelength of light: red, green and blue. The cones allow us to see images in colour and detail. Rods are responsible for night vision. They are sensitive to light but not to colour. In darkness, the cones do not function at all. How do we see an image? The lens focuses the image. It can do this because it is adjustable – using muscles to change shape and help us focus on objects at different distances. The automatic focusing of the lens is a reflex response and is not controlled by the brain. Once the image is clearly focused on the sensitive part of the retina, energy in the light that makes up that image creates an electrical signal. Nerve impulses can then carry information about that image to the brain through the optic nerve.
Endoscopic retrograde cholangiopancreatography, or ERCP, is a specialized technique used to study the bile ducts, pancreatic duct and gallbladder. Ducts are drainage routes; the drainage channels from the liver are called bile or biliary ducts. The pancreatic duct is the drainage channel from the pancreas.
A narrowing of the major artery (the aorta) that carries blood to the body. This narrowing affects blood flow where the arteries branch out to carry blood along separate vessels to the upper and lower parts of the body. CoA can cause high blood pressure or heart damage.
Nephrotic syndrome is a kidney disorder that causes your body to excrete too much protein in your urine. Nephrotic syndrome is usually caused by damage to the clusters of small blood vessels in your kidneys that filter waste and excess water from your blood. Nephrotic syndrome causes swelling (edema), particularly in your feet and ankles, and increases the risk of other health problems. Treatment for nephrotic syndrome includes treating the underlying condition that's causing it and taking medications. Nephrotic syndrome can increase your risk of infections and blood clots. Your doctor may recommend medications and dietary changes to prevent these and other complications of nephrotic syndrome.
Post-streptococcal GN is a form of glomerulonephritis. It is caused by an infection with a type of streptococcus bacteria. The infection does not occur in the kidneys, but in a different part of the body, such as the skin or throat. The strep bacterial infection causes the tiny blood vessels in the filtering units of the kidneys (glomeruli) to become inflamed. This makes the kidneys less able to filter the urine. Post-streptococcal GN is uncommon today because infections that can lead to the disorder are commonly treated with antibiotics. The disorder may develop 1 to 2 weeks after an untreated throat infection, or 3 to 4 weeks after a skin infection. It may occur in people of any age, but it most often occurs in children ages 6 through 10. Although skin and throat infections are common in children, post-streptococcal GN is a rare complication of these infections. Risk factors include: Strep throat Streptococcal skin infections (such as impetigo)
Sex easily falls to the wayside during pregnancy. Research shows that good sex has a significant impact upon not just the relationship, but also a woman’s ability to have an easeful and even joyful birth. Unfortunately, sex during pregnancy can be quite complicated for a variety of physical and emotional reasons. This week’s video will outline how to overcome these hurdles and make sure you continue to enjoy the wonders of sex as you embark on the first steps of parenthood.
A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery. A cataract can occur in either or both eyes. It cannot spread from one eye to the other.
Glycogen storage disease (GSD, also glycogenosis and dextrinosis) is the result of defects in the processing of glycogen synthesis or breakdown within muscles, liver, and other cell types. GSD has two classes of cause: genetic and acquired.
The pituitary gland is often portrayed as the "master gland" of the body. Such praise is justified in the sense that the anterior and posterior pituitary secrete a battery of hormones that collectively influence all cells and affect virtually all physiologic processes. The pituitary gland may be king, but the power behind the throne is clearly the hypothalamus. As alluded to in the last section, some of the neurons within the hypothalamus - neurosecretory neurons - secrete hormones that strictly control secretion of hormones from the anterior pituitary. The hypothalamic hormones are referred to as releasing hormones and inhibiting hormones, reflecting their influence on anterior pituitary hormones.
A glucagonoma is a rare tumor of the alpha cells of the pancreas that results in the overproduction of the hormone glucagon. Alpha cell tumors are commonly associated with glucagonoma syndrome, though similar symptoms are present in cases of pseudoglucagonoma syndrome in the absence of a glucagon-secreting tumor.
As a result, the amount of glucose in the blood increases while the cells are starved of energy. Over time, high blood glucose levels damage nerves and blood vessels, leading to complications such as heart disease and stroke, the leading causes of death among people with diabetes.
There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body's exterior.