Retinal detachment: A separation of the retina from its connection at the back of the eye. The separation usually results from a tear (that is, a rent or rip, not a tear drop) in the retina. The tear often occurs when the vitreous gel pulls loose or separates from its attachment to the retina, usually in the outside edges of the eye. The vitreous is a clear gel that fills most of the inside of the eye between the retina and the lens. If the retina is weak when the vitreous gel pulls loose, the retina will tear. This rip is sometimes accompanied by bleeding, or hemorrhage, if a blood vessel is also torn.

Once the retina has torn, liquid from the vitreous gel can then pass through the tear and accumulate behind the retina. The build-up of fluid behind the retina is what separates (detaches) the retina from the back of the eye. As more of the liquid vitreous collects behind the retina, the extent of the retinal detachment can progress and involve the entire retina, leading to a total retinal detachment. A retinal detachment almost always affects only one eye. The second eye, however, must be checked thoroughly for any signs of the problem.

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Salmon safety: The safety of eating salmon, especially farm-raised salmon. The levels of more than 50 pollutants, including polychlorinated biphenyls (PCBs), were determined in some 700 salmon from around the world. The results reported in 2004 indicated that farmed salmon have higher levels of toxic pollutants than wild salmon caught in the ocean and that the source of the toxic pollutants, as suspected, is the feed. The risks of eating salmon must be weighed against the known health benefits of salmon. See also: Feed contaminant.

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Bony syndactyly: A condition in which the bones of fingers or toes are joined together. Bony syndactyly is the opposite of cutaneous syndactyly, in which the bones are normal but skin between the digits is webbed.

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Ankyrin deficiency: Known also as hereditary spherocytosis (HS), this is a genetic disorder of the red blood cell membrane clinically characterized by anemia, jaundice (yellowing) and splenomegaly (enlargement of the spleen), due to deficiency of ankyrin, a protein in the membrane of the red cell.

In HS the red cells are smaller, rounder, and more fragile than normal. The red cells have a spherical rather than the biconcave-disk shape of the normal red cell. These rotund red cells (spherocytes) are osmotically fragile and less flexible than normal red cells and tend to get trapped in narrow blood passages, particularly in the spleen, and there they break up (hemolyze) leading to hemolytic anemia.

The clogging of the spleen with red cells almost invariably causes splenomegaly. The breakup of the red cells releases hemoglobin and the heme part gives rise to bilirubin, the pigment of jaundice. The excess bilirubin leads to the formation of gallstones, even in childhood, There is also often iron overload due to the excess destruction of iron-rich red cells.

Hereditary spherocytosis is most common in people of northern European ancestry. It often shows up in infancy or early childhood, causing anemia and jaundice. The bone marrow has to work extra hard to make more red cells. So, if in the course of an ordinary viral illness, the bone marrow stops making red cells, the anemia can quickly become profound. This is termed an aplastic crisis.

Laboratory studies show evidence not only of many spherocytes but also increased numbers of reticulocytes (young red blood cells), hyperbilirubinemia (increased blood levels of the jaundice pigment bilirubin due to the breakup of the red cells) and increased osmotic fragility of the red cells.

HS is due to a deficiency of a protein called ankyrin. Ankyrins are cell membrane proteins (thought to interconnect integral proteins with the spectrin-based membrane skeleton.) The ankyrin of red blood cells (erythrocytic ankyrin) is called ankyrin-R or ankyrin-1. It is represented by the symbol ANK1.

The HS gene, that for ANK1, has been mapped to chromosome 8 and, specifically, to chromosome band 8p11.2. HS is inherited as a dominant trait so, if a person with HS reproduces, their child (irrespective of whether it is a boy or girl) has a 50:50 chance to have HS.

The treatment of hereditary spherocytosis is to remove the spleen (splenectomy). Although the red cell defect persists, the breakup of the red cells (hemolysis) ceases. Splenectomy, however, is a hazard in young children. Young children without a spleen are at increased risk for overwhelming sepsis (bloodstream infection), particularly with the pneumococcus bacteria. Splenectomy is therefore usually postponed if possible until the age of 3 years. Before having a splenectomy, anyone with HS should have the pneumococcal vaccine. Persons with HS (or another cause of brisk ongoing hemolysis) should take supplemental folic acid.

The prognosis (outlook) after splenectomy is for a normal life and a normal life expectancy.

HS is also known as congenital hemolytic jaundice, severe atypical spherocytosis, spherocytosis type II, erythrocyte ankyrin deficiency, ankyrin-R deficiency, and ankyrin1 deficiency.

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Braxton Hicks contractions: Irregular contractions of the womb (the uterus) occurring towards the middle of pregnancy in the first pregnancy and, earlier and more intensely, in subsequent pregnancies.

These contractions tend to occur during physical activity. The uterus tightens for 30 to 60 seconds beginning at the top of the uterus; and the contraction gradually spreads downward before relaxing. Although said to be painless, Braxton Hicks contractions may be quite uncomfortable and sometimes difficult to distinguish from the contractions of true labor.

Not named for a Dr. Braxton and a Dr. Hicks but for John Braxton Hicks (1823-1897), a British gynecologist.

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Renal osteodystrophy: A combination of bone disorders usually caused by chronic kidney failure (renal disease). Can also occur because of abnormal kidney functioning at birth (congenital). When the kidneys have failed, death is imminent unless dialysis is given. Therefore, patients with osteodystrophy are usually on dialysis therapy. This bone disease, which is also simply called osteodystrophy, is common in patients on chronic hemodialysis.

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Cobalamin: Also called vitamin B12. A vitamin important for the normal formation of red blood cells and for the health of the nerve tissues. Undetected and untreated vitamin B12 deficiency can lead to anemia and permanent nerve and brain damage.

Pernicious anemia is a blood disorder caused by inadequate vitamin B12 in the blood. Patients who have this disorder do not produce the protein substance in the stomach that allows the body to absorb vitamin B12. This substance is called intrinsic factor (IF).

Pernicious anemia is simply treated with injections of vitamin B12. The vitamin B12 has to be administered by injection because people with PA do not have IF (or an effective form of IF) and so cannot absorb vitamin B12 taken by mouth.

Pernicious anemia has also been called Addison's anemia, addisonian anemia, Biermer's anemia.

Patients with Crohn's disease involving the small intestine (Crohn's ileitis) or who have undergone small intestine resection may not be able to absorb vitamin B12.

Strict vegetarians who consume no animal products can develop B12 deficiency since there is a lack of B12 in vegetables.

The recommended daily allowances of vitamin B12 in the United States are 2mcg for infants, 3 mcg for children under 4 years old, 6mcg for children over 4 years old and adults, and 8 mcg for pregnant women.

It is recommended for adults to take one multivitamin daily. One multivitamin a day is safe and inexpensive. The multivitamin should contain 400 micrograms of folic acid, approximately 2-3 mg of vitamin B6, 6-9 micrograms of vitamin of B12, and 400 IU of vitamin D. The folic acid and the other B vitamins can help lower homocysteine. The vitamin D is one of the important factors in preventing osteoporosis.

High blood homocysteine levels have been found to be a risk factor for atherosclerosis and heart disease. Most doctors will treat homocysteine levels higher than 9-10umol/liter. A doctor experienced in treating coronary heart disease should supervise the treatment of hyperhomocysteinemia. Treatment involves high doses of the B vitamins (1-5 mg/day of folic acid, 10mg/day of B6, and 0.4 mg/day of B12).

ALL vitamin supplements, with the exception of vitamin B12 supplement, are chemically synthesized. This means that they are produced by combining separate chemical elements in a factory. Vitamin B12 is biosynthesized, which means that it is made by using bacterial enzymes.

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Heart rhythm disorders: Abnormal rhythm of the heartbeat due to irregularities in transmission of the electrical signals that normally control heart rate and rhythm. Also known as arrhythmias. With an arrhythmia, the heartbeats may be irregular or too slow (bradycardia), too rapid (tachycardia), or occur too early. When a single heartbeat occurs earlier than normal, it is called a premature contraction. An abnormal heart rhythm can be due to electrical disturbances in the upper chambers of the heart (atria), the atrioventricular (AV) node, or the lower chambers of the heart (ventricles). Examples of atrial arrhythmias include atrial fibrillation, atrial flutter, and paroxysmal atrial tachycardia. Ventricular arrhythmias include ventricular tachycardia and ventricular fibrillation.

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Diverticulitis: Inflammation of the diverticula (small outpouchings) along the wall of the colon, the large intestine. (One outpouching is a diverticulum; two or more are diverticula).

For diverticulitis to occur, there must be diverticulosis, the presence of diverticula. Diverticulosis can occur anywhere in the colon but it is most typical in the sigmoid colon, the S-shaped segment of the colon the left lower part of the abdomen. (Sides are from the patient's perspective so the left lower part of your abdomen is nearest your left hand).

The incidence of diverticulosis increases with age. Age causes a weakening of the walls of the colon and this weakening permits the formation of diverticula. By age 80, most people have diverticulosis.

A key factor promoting the formation of diverticulosis is elevated pressure within the colon. The pressure within the colon is raised when a person is constipated and has to push down to pass small, hard bits of stool ("rabbit droppings").

Most patients with diverticulosis have few or no symptoms although some have mild symptoms including abdominal cramping and bloating.

Diverticulosis sets the stage for inflammation and infection of the outpouching, that is for diverticulitis. (The "-itis" refers to inflammation.) It is potentially serious and can result in pain in the left lower abdomen, fever, nausea, vomiting, constipation and, paradoxically, diarrhea and frequent urination. Even graver consequences such as perforation of the colon and peritonitis are well known from diverticulitis.

The best way to avoid developing diverticulosis in the first place (aside from the impossibility of staying young) is by eating a proper healthy diet With plenty of fiber. A diet high in fiber keeps the bowels moving, keeps the pressure within the colon within normal limits, and slows or stops the formation of diverticula.

Diverticulitis can be diagnosed with barium x-rays of the colon or with sigmoidoscopy or colonoscopy. Treatment of diverticulitis is designed to combat the inflammation and infection.

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Fertility awareness: Also known as natural family planning, periodic abstinence and the rhythm method, this approach entails not having sexual intercourse on the days of a woman's menstrual cycle when she could become pregnant or using a barrier method (such as a condom, the diaphragm or a cervical cap) for birth control on those days.

Because a sperm may live in the female's reproductive tract for up to 7 days and the egg remains fertile for about 24 hours, a woman can get pregnant in a substantial window of time -- from 7 days before ovulation to 3 days after. Methods to approximate when a woman is fertile are usually based on the menstrual cycle, changes in cervical mucus, or changes in body temperature.

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White phosphorus: A waxy solid which burns easily and is used in chemical manufacturing and smoke munitions. It is also used by industry to produce phosphoric acid and other chemicals for use in fertilizers, food additives, and cleaning compounds. Small amounts of white phosphorus were used in the past in pesticides and fireworks.

Breathing white phosphorus for short periods may cause coughing and irritation of the throat and lungs. Breathing white phosphorus for long periods may cause a condition known as "phossy jaw" which involves poor wound healing of the mouth and breakdown of the jaw bone.

Eating or drinking small amounts of white phosphorus may cause liver, heart, or kidney damage, vomiting, stomach cramps, drowsiness, or death. We do not know what the effects are from eating or drinking very small amounts of white phosphorus-containing substances over long periods of time. Skin contact with burning white phosphorus may burn skin or cause liver, heart, and kidney damage.

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Tocophobia: An abnormal and persistent fear of childbirth.

A phobia is an unreasonable fear that can cause avoidance and panic. Phobias are a relatively common type of anxiety disorder. Phobias can be treated with cognitive behavioral therapy using exposure and fear reduction techniques. In many cases, anti-anxiety or anti-depressant medication proves helpful, especially during the early stages of therapy.

Tocophobia is derived from the Greek "tocos" (childbirth) + "phobos" (fear).

A related term is teratophobia, fear of bearing a malformed child.

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Acoustic neurinoma: A benign tumor that may develop on the hearing and balance nerves near the inner ear. The tumor results from an overproduction of Schwann cells -- small sheet-like cells that normally wrap around nerve fibers like onion skin and help support the nerves. When growth is abnormally excessive, Schwann cells bunch together, pressing against the hearing and balance nerves, often causing gradual hearing loss, tinnitus (ringing in the ears), and dizziness. If the tumor becomes large, it can interfere with the facial nerve, causing partial paralysis, and eventually press against nearby brain structures, becoming life-threatening.

The early diagnosis of an acoustic neurinoma is the key to preventing its serious consequences. Unfortunately, early detection of the tumor is sometimes difficult because the symptoms may be subtle and may not appear in the beginning stages of growth. Once the symptoms do appear, a thorough ear examination and hearing test are essential for diagnosis. Computerized tomography (CT) scans and magnetic resonance imaging (MRI) are helpful in determining the location and size of a tumor and also in planning its microsurgical removal.

If an acoustic neurinoma is surgically removed when it is still very small, hearing may be preserved and accompanying symptoms may go away. As the tumor grows larger, surgical removal is often more complicated because the tumor may become firmly attached to the nerves that control facial movement, hearing, and balance.

The removal of tumors attached to hearing, balance, or facial nerves can make the patient's symptoms worse because sections of these nerves must also be removed with the tumor. As an alternative to conventional surgical techniques, radiosurgery may be used to reduce the size or limit the growth of the tumor. Radiosurgery, utilizing carefully focused radiation, is sometimes performed on the elderly, on patients with tumors on both hearing nerves, or on patients with a tumor growing on the nerve of their only hearing ear. If the tumor is not removed, MRI is used to carefully monitor its growth.

There are two types of acoustic neurinoma: unilateral and bilateral. Unilateral acoustic neurinomas affect only one ear. They account for approximately 8 percent of all tumors inside the skull. Symptoms may develop at any age but usually occur between the ages of 30 and 60 years.

Bilateral acoustic neurinomas, which affect both ears, are hereditary. Inherited from one's parents, this tumor results from a genetic disorder known as neurofibromatosis-2 (NF2). Affected individuals have a 50 percent chance of passing this disorder on to their children. Unlike those with a unilateral acoustic neurinoma, individuals with NF2 usually develop symptoms in their teens or early adulthood. Because NF2 patients usually have multiple tumors, the surgical procedure is more complicated than the removal of a unilateral acoustic neurinoma. Further research is needed to determine the best approach in these circumstances.

In addition to tumors arising from the hearing and balance nerves, NF2 patients may develop tumors on other cranial nerves associated with swallowing, speech, eye and facial movement, and facial sensation. NF2 patients may also develop tumors within the spinal cord and on the brain's thin covering.

Both types of acoustic neurinoma occur following a loss of the function of a gene on chromosome 22. A gene is a small section of DNA responsible for a particular trait like hair color or skin tone. This particular gene on chromosome 22 suppresses the growth of Schwann cells. When this gene malfunctions, Schwann cells can grow out of control. This gene may help suppress other types of tumor growth. In NF2 patients, the faulty gene on chromosome 22 is inherited.

Acoustic neurinoma is also called an acoustic neuroma or a vestibular schwannoma.

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Parkinson disease: A slowly progressive neurologic disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40. Also known as paralysis agitans and shaking palsy.

Treatment is by medication, such as levodopa (Larodopa) and carbidopa (Sinemet). A surgically implanted device that helps control the shaking has recently become available. In some cases, surgery on the globus pallidus or thalamus has proved helpful.

From a genetic viewpoint it is now clear that Parkinson disease is heterogeneous. It is not one, but a number of diseases. Genes appear to be involved in all forms of Parkinson disease. See also: Parkinson disease gene.

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Hospice care: Care designed to give supportive care to people in the final phase of a terminal illness and focus on comfort and quality of life, rather than cure. The goal is to enable patients to be comfortable and free of pain, so that they live each day as fully as possible. Aggressive methods of pain control may be used. Hospice programs generally are home-based, but they sometimes provide services away from home -- in freestanding facilities, in nursing homes, or within hospitals. The philosophy of hospice is to provide support for the patient's emotional, social, and spiritual needs as well as medical symptoms as part of treating the whole person.

Hospice programs generally use a multidisciplinary team approach, including the services of a nurse, doctor, social worker and clergy in providing care. Additional services provided include drugs to control pain and manage other symptoms; physical, occupational, and speech therapy; medical supplies and equipment; medical social services; dietary and other counseling; continuous home care at times of crisis; and bereavement services. Although hospice care does not aim for cure of the terminal illness, it does treat potentially curable conditions such as pneumonia and bladder infections, with brief hospital stays if necessary. Hospice programs also offer respite care workers, people who are usually trained volunteers, who take over the patient's care so that the family or other primary caregivers can leave the house for a few hours. Volunteer care is part of hospice philosophy.

The word "hospice" comes from the Latin "hospitium" meaning guesthouse. It was originally described a place of shelter for weary and sick travelers returning from religious pilgrimages. During the 1960's, Dr. Cicely Saunders began the modern hospice movement by establishing St. Christopher's Hospice near London. St. Christopher's organized a team approach to professional caregiving, and was the first program to use modern pain management techniques to compassionately care for the dying. The first hospice in the United States was established in New Haven, Connecticut in 1974. Today more than 3,000 hospice programs across the country offer comprehensive hospice care. Most insurance plans in the US include hospice as a covered benefit.

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Glucose tolerance test: A blood test done to make the diagnosis of diabetes mellitus. The test may also be done for other purposes such as to diagnose hypoglycemia (low blood sugar) or a malabsorption syndrome in which sugar is not absorbed properly through the intestines into the bloodstream.

The test was designed originally to determines the tolerance for the sugar glucose. "Tolerance" refers to the body's ability to handle (tolerate) glucose. However, the test is not that simple. The test depends on a number of factors including the ability of the intestine to absorb glucose, the power of the liver to take up and store glucose, the capacity of the pancreas to produce insulin, the amount of "active" insulin it produces, and the sensitivity of the cells in the body to the action of insulin.

For the test, you fast overnight and then are given a specific amount (100 grams) of glucose by mouth and then your blood glucose levels are monitored for 3 hours. Normally, the blood glucose should return to normal within 2 to 2½ hours. The outcome of the test may indicate:

• Normal glucose tolerance
• Abnormal glucose tolerance
  • Depressed glucose tolerance -- in which the blood glucose peaks sharply before declining slower then usual to normal levels -- as in:
    • Diabetes mellitus
    • Hemochromatosis (iron overload disease)
    • Cushing syndrome (too much cortisol ["cortisone"] hormone)
    • Pheochromocytoma (adrenaline-producing tumor)
    • Central nervous system lesions
  • Increased glucose tolerance -- in which the blood glucose levels peak at lower than normal levels -- as in the:
    • Malabsorption syndrome
    • Insulinoma (an insulin-producing tumor)
    • Addison disease (adrenocortical insufficiency)
    • Hypopituitarism (underactivity of the pituitary gland)
    • Hypothyroidism (underactivity of the thyroid gland)

Since the dose of glucose is taken by mouth, the test is sometimes called an oral glucose tolerance test.

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Puerperium: The time immediately after the delivery of a baby. (In Latin a "puerpera" is a woman in childbirth since "puer" means child and "parere" means to give birth.) Puerperal fever is childbirth (or childbed) fever due to an infection usually of the placental site within the uterus. If that infection involves the bloodstream, it constitutes puerperal sepsis.

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Keratosis follicularis: A genetic skin disease characterized by slowly progressive hardening of the skin (keratoses) around the hair follicles. This disorder is inherited in an autosomal dominant manner and is due to mutation in a gene called ATP2A2 on chromosome 12. Also known as Darier disease.

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Bed bugs: Bed bugs are small, oval, wingless insects of the family Cimicidae, which have a flat, reddish-brown body and feed on human and animal blood. Bed bugs are active at night and bite any areas of exposed skin. Bed bugs can infest a home and hide in crevices or cracks around beds or furniture. While some bites may go unnoticed, bed bug bites may also result in localized swelling and itching, and the areas may become inflamed or infected when scratched. Bed bugs are not believed to transmit diseases to humans.

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Gynecoid obesity: A fat distribution generally characteristic of that of a woman, around the hips, etc.

Gynecoid means like a woman, womanly, female. The word gynecoid comes from the Greek gyno, gynaikos meaning woman. Gyneco-, gyno-, gyn-, and gyne- are combining forms meaning woman. For examples:

• Gynecoid pelvis: A pelvis that is shaped like a woman's.
• Gynecology: The study of the diseases of the female reproductive organs and the breasts.
• Gynecomastia: Excessive development of the male breast (so that it is female-like).

Male obesity is a fat distribution characteristic of a man, with a paunch, etc.

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