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Eighth Nerve Tumors

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A tumor can affect the al nerve and produce a neurofibromatosis. The symptom is usually a slow process, a terrible deafness of the sensory type that gradually worsens. Tinnitus accompanies it, and this gradually extends over 20-30 years. Dizziness in mild forms may occur, but this is seldom severe, the patient noticing clumsiness in walking. Vertigo may take place, and it may be confused with MeniCre’s disease. Later on there is involvement of other nerves, chiefly the facial nerve, that gives the telltale clue and makes a final diagnosis fairly certain.

However, in recent times, improved methods of diagnosis are bringing more to treatment at an earlier stage, Treatment is surgical, and current methods may produce relatively good results.

Eye Care

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The eye is a marvel of engineering. Each eye is a compact but exquisitely sensitive biological camera that focuses images of the external world onto the retina, a ten-layer cellular membrane directly connected to the brain through the optic nerve. Before arriving at the retina (located at the back of the eyeball), light must pass through

  • the cornea, a clear, highly sensitive structure that forms a domelike covering over the iris, whose pigment gives the eye its color;
  • the pupil, the small black circular aperture (opening) in the center of the iris. The pupil dilates or constricts in response to the amount of light striking the eye;
  • the lens, placed directly behind the iris, which focuses light on the retina;
  • the vitreous humor, clear gelatinous material that fills the eyeball.

Vision disturbances can arise from abnormalities in the shape, function, or clarity of these structures.

Other important structures of the eyes are the sclera, the white surface of the eyeball; the conjunctiva, a membrane that covers the sclera and the inner surfaces of the eyelids; the lacrimal gland, which produces tears; and the nasolacrimal duct, through which tears travel from the inner corner of the eye into the nose.

Even though a baby’s eyes are not fully developed at birth, the intricate process of collecting visual information begins as soon as a newborn can open her eyes. The retina is not fully functional during the first few months, and the brain needs time to assemble visual images into meaningful patterns. Nevertheless, during the first few weeks of life, a baby will gaze intently at objects 8 to 15 inches from her face. She prefers to study plain, high-contrast, black-and-white images such as stripes, checks, or spirals, or a simple drawing of a face. But a newborn’s favorite subject to scrutinize will be a person’s face about a foot away frosts hers. She will not respond directly to a smile for the first few weeks.

The iris in a light-skinned newborn contains little pigment and is usually blue gray or blue brown. The final color of a baby’s eyes won’t be known for at least six months or longer, during which time pigment gradually forms. The iris is brown from birth in most dark-skinned infants. The lacrimal gland does not become fully functional for about four weeks, so the crying new-born makes few tears. The sclera is relatively thin at birth and may have a slightly bluish tinge because of the dark color of the tissue lying just beneath it. A rise in bilirubin level shortly after birth may cause the sclera to appear yellow.

By two or three months of age a baby will be able to coordinate her eye movements to stay locked on an interesting visual target that passes through a semicircle in front of her. She will also be interested in more complex shapes and patterns and will be able to hold her head steady enough to fixate on simple, high-contrast objects hung over her crib. By three months of age her depth of vision will have increased so that she will recognize you halfway across a room. Responses to color also develop over the first several weeks. At first, a newborn will pay attention to objects with bright, strongly contrasting colors. It will take a few months before the color vision has matured enough to distinguish a full palette of colors and shades.

All babies cross their eyes briefly as they develop their tracking skills. However, an infant who does not follow a face by the age of three months or whose eyes frequently wander or cross after five or six months may have a visual problem that should be addressed by the pediatrician or family doctor. The primary-care doctor will examine the eyes and, if appropriate, refer the patient to an ophthalmologist for evaluation. (Ideally this would be a pediatric ophthalmologist – a physician who specializes in children’s eye problems – although many ophthalmologists deal with patients of all ages.)By six months of age an infant is normally able to focus on people or objects several feet away and follow movement in all directions. Visual acuity, or ability to see objects, will improve from approximately 20/400 at birth to about 20/80. (The numbers used to express visual acuity arc based on the ability to identify letters at certain distance. A visual acuity of 20/80 means that the smallest letters a person can identify 20 feet away could be read by someone with normal (20/20) vision at a distance of 80 feet. Obviously infants cannot identify letters, but their visual acuity measured by other methods is still expressed in the 20/ format.) A six-month-old will also show interest in more complex patterns and subtle shades of color.

By seven or eight months, a baby’s visual capabilities will mature to the point that she can focus en people and objects across the room, though not quite with the clarity with which she sees whatever is directly in front of her. The average one-year-old can see well enough to see small objects across the room or planes flying over land, and by the age of two a child’s visual acuity can approach 20/30 or 20/20, although this can be difficult to establish objectively. A child age two or older that squints a lot or brings objects close to her face should have a formal eye exam, as should a stint, who is old enough to complain specifically of blurt vision or difficulty seeing the blackboard at school. Routine infant and childhood exams include a full check of the eyes: the clarity of each cornea, appearance of the eyelids, and responses of the pupils. Children young as three can be screened for visual acuity with an appropriate eye chart or other testing methods the child can comprehend.

Eye Problems

Common Eye Problems during Infancy

Chronic mucous drainage (nasolacrimal duct obstruction) is caused by a blockage of a baby’s now lacrimal duct, which normally drains tears into the nose after they have entered small openings in the corner of each eye. Six to 10 percent of infuses are born with an obstruction of this duct. Within days or weeks after birth, tears will accumulate and overflow from the affected eye. The small lacrimal located just above the obstructed duct may become infected, causing a constant backflow of discolored mucus into the eye. This usually bothers parents more than the baby, but more severe signs of infection such as inflammation and swelling may develop in the awe-corner of the eye.

If the baby’s primary-care physician diagnosis has a problem, he or she might recommend warm soup, a massage of the tear duct up to six times per day (done by pressing the tip of a finger against the nose just above the lacrimal sac) (in the area where the upper and lesser eyelids come together) and pinning downward toward the nasolacrimal duct. Antibiotic drops or ointment may be prescribed if an infection is present.

More than 70 percent of obstructed nasolacrimal ducts will open before the child is three months old, 90 percent will open by nine months. If the problem does not resolve spontaneously, a probing, which involves placing a thin wire probe through the obstacle, can be done in the office (or hospital) between three and nine months.

Strabismus is a misalignment of the eye. An eye may squint inward (esotropia), outward (exotropia), up (pertropia), or down (hypotropia). Strabismus occurs in 4 to 5 percent of infants. Since eye movements are notably coordinated until the child is three to six month old, temporary deviations in any direction before the age of three months usually do not require specific treatment. However, persistent deviation after the age of six months should be checked by the baby’s physician, and usually the physician will refer the patient to an ophthalmologist. Appropriate treatment of strabismus is important because misalignment of the eyes causes ongoing troubled vision, causing the infant’s brain to suppress in – formation arriving from one eye or the other. This results in an impairment of vision called amblyopia, which develops in 2 to 4 percent of individuals. Depending on the extent of the strabismus, correction may require the use of special glasses or even muscle surgery on one or both eyes. The operation, usually done on an outpatient basis, modifies the attachment positioning one or more of the muscles that control eye movements.

Common Eye Problems during Childhood

So far the most common vision disorders in children are refractive errors, in which the retina does not receive a perfectly focused image. These affect 20 percent of children by the age of 16. Since genetic factors play a role in these disturbances, other family members may have similar problems. There are several types of refractive errors:

  • Myopia (nearsightedness) – distant objects are out of focus. This condition usually develops as the eyeball grows and becomes longer than is ideal for focusing images on the retina. Normally myopia is not seen until a child is five to ten years of age, and it may become more pronounced during adolescence and early adulthood. A near-sighted child may squint because this helps bring distant objects into focus.
  • Hyperopia (farsightedness) – distant objects are more easily brought into focus than those that are close. This condition is present in 80 percent of newborns, a consequence of the smaller size of a baby’s eye. Normal alterations in the shape of the newborn’s lens and cornea compensate for hyperopia early in infancy. Farsightedness may actually become more pronounced during the first few years of life, but a child’s eye has a greater capacity than an adult’s to adjust the shape of the lens (a process called accommodation), which effectively brings a close object into focus. However, hours of this effort can cause eyestrain, headaches, and crossed eyes.
  • Astigmatism is an abnormality in which the cornea is more egg-shaped than round, producing blurry or distorted vision. Squinting may improve a child’s focus when astigmatism is present, but a severe distortion can cause eyestrain and headaches.

Refractive errors can be corrected with glasses or contact lenses. Mild hyperopia is usually not treated. Children who are highly active should use shatterproof lenses. Youngsters involved in sports can wear an elastic strap that attaches to the glasses and extends around the back of the head to keep them in place and prevent loss or damage.

Eye trauma, ranging from a scratch on the cornea to a severe injury that causes permanent visual impairment or loss, is not uncommon in childhood. According to the U.S. Public Health Service, more than 100,000 eye in-juries occur every year in the United States, of which 90percent are preventable. (Injuries due to darts, BB guns, and firecrackers are all too common.

A corneal abrasion is a scratch in the cornea’s outer cell layers, often caused by a seemingly minimal incident such as being brushed by a leaf or twig. Since the cornea is very sensitive, the pain of an abrasion is usually intense. After the eye is examined by a doctor or ophthalmologist, an antibiotic is usually placed on the eye and a patch applied to pre-vent the eyelid from opening and closing over the in-jury. The antibiotic helps prevent secondary infection that could lead to more serious damage of the cornea. The surface of the cornea normally heals completely within 24 to 48 hours.

Sometimes trauma will cause internal bleeding of the eye, resulting in extreme pain and clouded vision. When blood appears in the clear space behind the cornea (a condition called a hyphenate child should be taken immediately to an ophthalmologist or emergency room. To prevent further bleeding, the child must be kept at strict bed rest for up to five days. Enforcement of this low level of activity is critical. If the blood is not absorbed, an operation might be needed to remove it. A hyphema can cause scarring of the eye, which can in turn produce glaucoma (increased pressure within the eye). Further eye exams may be conducted to ensure that no additional damage has occurred.

If the eyeball has been penetrated or cut open, the child should be taken directly to the emergency room for immediate evaluation. If fluid is oozing front the eye, the child should be transferred while lying flat on her back so that additional fluid will not escape from the eye. A simple shield such as a small paper cup should be held over the eye (but without exerting pressure) to protect it. A chemical injury to the eye, especially from an alkaline substance such as drain cleaner, can be very damaging and difficult to treat. It is important to flush any such material out of the eye with prolonged irrigation. Immediately place the face under a water faucet or hose and rinse the eye. Then promptly see an ophthalmologist or go to a hospital.

A foreign object (such as a piece of dirt) in the eye will cause irritation, pain, and tearing. Sometimes a parent can locate the foreign body under the upper or lower eyelid and gently remove it. If the object’s size or location or the child’s discomfort prevents removal at home, the child’s doctor or an ophthalmologist should be contacted. Usually an anesthetic drop will be placed in the eye so the foreign body can be removed without pain. Eye infections can be caused by viruses, bacteria, or fungal agents. Common symptoms of an eye infection are redness, tearing, watery or mucous drainage, and mild sensitivity to light. Significant pain in one or both eyes, with or without sensitivity to light, should not be ignored. In such cases, the child should be examined by her physician or an ophthalmologist, not only to relieve the discomfort but to treat conditions that might damage the eye if left alone.

Any virus or a bacterium that infects the nose or throat can find its way into the linings of one or both eyes (or conjunctivae). Infections here, known as conjunctivitis, produce a reddish discoloration and thick, discolored drainage. When this material dries overnight, the eyelids may stick together with crusty debris, which you will need to remove gently with a warm, wet washcloth. Your child’s doctor will normally prescribe antibiotic drops or ointment for a few days. If the infection is caused by a virus (such as the common adenovirus, which is usually accompanied by an upper-respiratory-tract infection, fever, and sore throat), symptoms may not resolve for several weeks. Careful hand washing is a must for anyone handling a baby with conjunctivitis because the organisms involved can spread to others via contaminated fingers (see conjunctivitis).Various forms of the herpes virus can on rare occasion cause problems on the surface of (or deeper within)the eye. Chicken pox (varicella) occasionally causes conjunctivitis if the virus forms one or more small blisters (similar to those on the skin surface) on the conjunctiva of the eye. These normally resolve without damage. A reappearance of the chicken pox virus later on in life, known as herpes roster, or shingles, can also involve the cornea. In addition, the herpes simplex virus which causes common cold sores of the lips, may affect the eye. Treatment of any herpes infection involving eye will require an ophthalmologist to relieve discomfort and prevent rare complications that can cause scarring long-term visual impairment.

Allergies can cause itchy and runny eyes, a condition known as allergic conjunctivitis, which often respond to antihistamines. In some cases eye drops containing antihistamines or other anti-inflammatory substances can help reduce symptoms, although they do not provide cure. Thick mucus, crusting, and pain are not a part of this problem, and causes other than allergy should be considered. In more severe allergic reactions, swelling of the conjunctival membrane occurs, producing a bubble on the surface of the eye or inner lids. This can look frightening, but it resolves without harming the eye.

Problems with the Eyelids and the Iris

The eyelids can be the site of both inflammation and infection. Blepharitis is a chronic condition that causes swelling and redness of the eyelids and a scaling dandruff-like material from the eyelashes. Often blepharitis is caused by bacteria called staphylococci, but may also be related to an inflammatory condition called seborrhea. Treatment involves removing the crust with a moist cotton applicator (which may be dipped in baby shampoo diluted with an equal amount of water). Antibiotic ointment may also be useful.

A hordeolum, better known as a sty, is a staphylococcal infection of a gland in the eyelid. This usually begins as a tiny red spot that grows into a pustule, which will eventually drain. Warm com-presses may be applied three or four times a day, and antibiotic drops can be helpful. Inflammation of a different type of gland in the eyelid leads to a small lump called a chalazion. Warm soaks are also helpful, although this condition may take up to three months to resolve. Rarely a chalazion will not disappear, and surgical removal under anesthesia becomes necessary. The persistence of blepharitis or a chalazion is often discouraging to parents but most children will outgrow these problems. As mentioned earlier, persistent pain in the eye, especially when discomfort is aggravated by light, should be evaluated as soon as possible. One condition that may cause this combination of symptoms is iritis, or inflammation of the iris. Frequently this is accompanied by redness of the sclera, which may give the misleading impression that a child has the more common conjunctive pinkeye. But iritis must be treated quite differently to relieve pain and prevent scarring of the iris and other eye structures. In children, iritis is often associated medical conditions that affect other parts of the most commonly juvenile rheumatoid arthritis. Further evaluation to search for one of these disorders will probably be recommended.

Influenza

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Better known as flu, an acute infection, that frequently occurs in epidemics or occasionally in world-wide outbreaks known as pandemics. Three types of influenza virus, known simply as types A, B, and C, have been identified; A and B are responsible for nearly all epidemics. Unfortunately, each of the three types has a number of different strains, and the virus undergoes subtle biochemical changes on an ongoing basis. As a result, someone who catches the flu or is vaccinated this year usually will not be immune during next year’s out-break. That is why those who need flu shots must get anew one each year. Influenza is typically seen in the United States and Canada in the fall and winter, usually involving strains that have been identified a few months earlier in Asia. These outbreaks develop quickly, spread rapidly, and may involve sizable numbers of people in a given community. While complications and mortality are uncommon in healthy individuals, influenza can be serious for children who have chronic illnesses.

Influenza Symptoms

Influenza is characterized by the sudden onset of chills, fever, muscle aches, headache, lack of appetite, and a dry cough. Nausea, vomiting, and abdominal pain some-times occur in younger children but are less common in adolescents or adults. (Acute gastroenteritis, often called stomach flu, is an entirely different type of infection.) In some children, influenza can appear to be a simple respiratory-tract infection or an illness with fever but without any cold or cough. Influenza does not cause a rash or intense inflammation of the throat (pharyngitis). If bacteria become involved as secondary invaders, complications such as bronchitis, sinusitis, middle-ear infection, and pneumonia could develop. Flu is spread via respiratory secretions that become airborne with coughing or are passed person to person by unwashed hands. A child or adult is most contagious for a period extending from 24 hours before the onset of symptoms through the time they show signs of resolving. The incubation period (the time from exposure to onset of symptoms) is one to three days.

Influenza Treatment

Treatment of influenza is usually focused on relief of symptoms. Acetaminophen (Tylenol and other brands) or ibuprofen (Children’s Motrin and other brands) can be used to relieve fever and aches, but aspirin should be completely avoided because of the risk of Reye’s syndrome. The child should drink a lot of fluids. (There is usually not much appetite for solids until symptoms begin to abate.) Until the fever, aches, and cough have calmed down for 24 hours, the child should remain at home and quiet. Antibiotics will have no effect on the course of the illness, although they can be helpful if secondary bacterial infections develop.

Two drugs, amantadine and rimantadine, may reduce the severity of symptoms if given within the first 48hours of the onset of a type A influenza virus infection. (The type of virus involved in a local epidemic may be identified by the local health department.) They can also prevent influenza from spreading to other family members. These drugs are not routinely given to children, since influenza normally resolves without treatment in two to five days. Your child’s doctor can advise you whether one of these medications might be helpful or necessary.

A flu vaccine is developed each year and given every fall. It is not recommended for all children but should be considered annually for those with chronic conditions such as heart disease, asthma, kidney failure, and disorders of the immune system. For children with these and other long-term medical problems, influenza can be a much more serious (or even fatal) illness. Other family members in the home of a high-risk child should be vaccinated as well. Flu vaccine can be given to infants as young as six months of age, although it is less effective its younger children.

Some parents may choose to vaccinate children who do not have chronic illnesses to minimize the risk of their missing school or other important activities.

Food and Vitamins

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When food is eaten, the teeth and oral cavity are geared to break large food particles into smaller ones that may be swallowed with ease. The food is mixed with saliva, which contains weak chemicals that put the process of digestion into operation. From the oral cavity, the food slips into the food tube called the esophagus. This tube has a small valve at the far end, called the cardiac valve. This opens at regular intervals, enabling the food mass (called a bolus) to enter the stomach. The stomach is merely a dilated portion of the digestive system. It is lined with specialized cells that actively secrete a powerful acid (hydrochloric acid) and certain digestive juices. Here digestion of the food really gets under way. The food particles are reduced into still smaller particles, until a thick fluid volume is produced. From here, the food passes through another valve, called the pylorus, into the next part of the intestinal (or digestive or bowel) system, called the duodenum. Here there is a prolongation and intensification of the digestive process. Gradually the duodenum empties the food into the next part, the so-called small intestinal system. This is the lengthy bowel system, and here digestion continues. This is also where the final ingredients of the broken-clown food are actively absorbed by the cells lining the bowel wall and pass into the bloodstream. Apart from the gaseous interchange occurring, other vital blood-borne products are also deposited at these points – food, vitamins, enzymes, immunological agents. The great carrying capacity of the blood fluid is fully taken advantage of at this juncture.

Just as carbon dioxide is passed back into the blood, so other waste products of the body’s metabolism are also injected into the blood. These are unwanted chemicals and other contaminants that are totally useless at the cell face.

As these are passed back into the fluid of the blood, the circulation rapidly moves onwards. The capillaries commence to link up with larger vessels, and these in turn join bigger ones called venules. As venules flow into still larger ones, called veins, the total oxygen-reduced blood accumulates. The blood enters larger and still larger veins until it finally flows into a major one that conveys it directly back into the right-hand atrium of the heart once more.

There is a relatively small volume of blood in your body, but it is recycled continuously throughout the system.

If you would like to know how much blood is in your body, you can work it out with this simple sum. Check your body weight on the scales. Now for each kilogram of body weight, the body contains 60 – 80 ml of blood. So if you weigh about 50 kg (approximately 8 stone), and are a nice trim female, and allow an average of 70 ml for each kg, it works out as: 50 kg x 70 ml = 3500 ml, or 3.5 litres of blood.

Considering the tremendous amount of work the blood does, and the remarkable load of material it carries, this is efficiency of the highest order.

If human beings applied this same efficiency to their own physical output of work, in terms of achievement, the net effect would be earth-shattering.

The nation’s highway system would be built in a few weeks; the total work-entailing programs would be finished in record time. Perhaps this would not be a good thing, for very soon there would be nothing left to do. Then humans might turn to warfare and bloodshed again, and totally revoke all the good that had been done. But they are doing this anyway, so what’s the difference? Maybe it is food for contemplation.

For the heart to be able to carry this enormous, incessant workload it must receive a substantial amount of oxygen and food supplies itself. It cannot receive this directly from the fluid it pumps, for this is purely a mechanical procedure, and the blood flows through the cardiac chambers.

However, the heart has an important circulation buried in the deep tissues of the heart muscle. This is termed the coronary blood supply, and it plays a vital part throughout life.

Major vessels gradually branch out through the heart structure, taking valuable supplies to every part. Similarly, a venous system collects this deoxygenated blood to take it back via the general circulation to the lung system.

It is essential that the efficiency of these heart vessels be maintained throughout life. Unless they are, problems loom. If the heart is deprived of its vital elements, then it is no longer capable of operating at peak efficiency.


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