Online Medical Dictionary

Letter B

B Cell
One of the main types of lymphocytes, along with T cells; white blood cells.
B Virus
An infectious agent found in some species of monkeys.
Back Pain, low
Pain experienced in the lower back that may indicate issues with the lumbar spine, lower back muscles, internal organs situated within the pelvis and abdomen, or skin covering the pained area.
The spine; the row of bones descending from the base of the skull to the tailbone.
A condition wherein live bacteria are present in the bloodstream. Also termed bacillemia.
Single-celled microorganisms free-living as independents or as parasites, dependent on other organism to sustain existence.
An abnormal and persistent fear of bacteria or germs.
Balloon Angioplasty
Coronary angioplasty, wherein the coronary artery, narrowed by the buildup of cholesterol-produced plaque, is enlarged by the use of a balloon-tipped catheter inserted through the groin or arm into the artery.
The involuntary action of urinating while in bed. Also termed enuresis.
Behavioral Therapy
Method of treatment involving the substitution of undesirable responses or behaviors with desirable ones.
Behavioral Medicine
An interdisciplinary medical field concerned with altering undesirable behaviors, such as drug abuse, with behavioral therapy techniques such as relaxation training, hypnosis and biofeedback.
Behind-the-ear Hearing Aid
Hearing aid worn on the back of the ear, behind the ear lobe, amplifying sounds for those who have experienced hearing loss.
That which does not threaten health or life. More commonly refers to a benign tumor, meaning a tumor that is not malignant or cancerous.
The period of grief and mourning experienced after a loss.
Berry Aneurysm
A small out pouching of a berry-like appearance, usually occurring at the base of the brain, where the cerebral artery departs from the circular artery. Also referred to as a brain aneurysm.
A fluid, yellow and green in colour, produced by the liver and stored in the gallbladder. Bile passes through a duct into the duodenum where it aids in the digestion of fat. Bile is composed mainly of cholesterol, the pigment bilirubin and bile salts.
Relating to both ears. Hearing aids may be placed in both ears (binaural) or placed in one ear (monaural).
Binge Eating Disorder
An eating disorder marked by bouts of excessive over-eating, however is not followed by periods of purging as is common in most cases of bulimia. Binge eating disorder can contribute to weight gain, diabetes, high blood pressure and heart disease.
Binocular Vision
The ability to maintain visual focus with both eyes, creating a single visual image of the object in view. Individuals lacking in binocular vision experience visual misrepresentations of depth perception or perceived distances.
The ability to have effect or to interact with anything living. Bioactive substances include antibiotics, vitamins and enzymes.
The study and application of chemical processes in living organisms.
A treatment method utilizing monitors to relay physiological information, of which the patient is usually unaware, back to them to aid them, through a process of trial and error, to adjust their negative mental processes. Used to aid patients suffering from conditions such as anxiety, addiction and depression to control their involuntary reactions. Aids in normalizing functions such as blood pressure, gastrointestinal functioning, brain wave activity and body temperature.
Biological Therapy
Any form of treatment or therapy that employs the body's natural immune system abilities to fight or guard against treatment side effects, infection or disease. Also termed immunotherapy and biotherapy.
The extracting of a tissue sample for the purpose of diagnosis.
Bipolar Disorder
A mood disorder usually involving rapid and dramatic cycles of depression then mania, or elation. Also referred to as manic-depressive illness or manic-depression.
Birth Defect
Any defect present at birth, regardless of the cause being genetic or non-genetic.
Birth Rate
Usually calculated as the number of live births to the average population of the area for which the rate is being deduced.
Black Lung Disease
A chronic disease of the lungs contracted through prolonged inhaling of coal dust.
The pouch-like organ situated in the lower abdomen which functions to stores urine.
Bladder Cancer
Cancer usually forming out of a superficial tumor situated in the lining of the bladder. Symptoms include blood in the urine stream, pain during urination and frequent need to urinate or the feeling of needing to urinate with no results. Can be confirmed through a bladder biopsy.
Bladder Infection
Infection of the bladder, also termed a urinary tract infection(UTI). Experienced by 20 per cent of women.
Bladder Inflammation
Inflammation of the bladder commonly caused by bacteria. Also termed cystitis.
Blood Cleaner
A process by which the majority of possible pathogens, such as bacteria, fungi and viruses, are cleansed from blood that has been donated. Also called pathogen inactivation.
Blood Clot
Blood that has been coagulated by the body to form a solid mass, which can become dangerous depending on physiological position. Also termed a thrombus. The blood clot is referred to as an embolus if it should travel.
Blood Culture
A test to determine the presence of any microorganisms, such as bacteria and fungi, in blood.
Blood Glucose
The simple sugar that the body produces out of the food it consumes. Glucose is carried through the bloodstream to provide energy to cells, which digest the energy with the aid of insulin.
Blood pH
Blood acidity or alkalinity. Normal blood pH levels between 7.35 and 7.45.
Blood Poisoning
Septicemia; the presence of pathogenic microorganisms and/or the toxins they emit in the bloodstream.
Blood Pressure
The pressure of the blood within the arteries produced by the contracting of the heart muscle. Blood pressure is recorded in two numbers: systolic pressure, the higher number, measured after the heart contracts; and diastolic pressure, the lower number, measured before contraction.
Blood Pressure, high
Hypertension; blood pressure exceeding a systolic pressure of 140 with a diastolic pressure of 90.
Blood Pressure, low
Hypotension; blood pressure measured below the normal expected blood pressure for an individual in their circumstances.
Blood Sugar
See Blood Glucose.
Blood Transfusion
The transfer of blood, or its components, from the bloodstream of a donor to that of a recipient.
An anticoagulant agent used to prevent blood clots from coagulating.
Body mass index.
BMI Calculation
An individual's weight in kilograms divided by their height in meters, squared.
Abbreviation for bone marrow transplantation.
Body Dysmorphic Disorder
Psychiatric disorder in which patient is excessively preoccupied with imagined defects in their physical appearance.
Body Type
Refers to the three classic body shape types: ectomorphic, mesomorphic and endomorphic.
Any therapeutic or relaxing practice that involve manipulation, massage or regimented body movement.
Boerhaave's Syndrome
The spontaneous tear and rupture of the esophagus, usually requiring surgery.
A collection of pus abscessed in the skin.
Bone Cancer
Malignancy in the bone, commonly originating from cancer in another area in the body, with a tendency to further spread and cause a great deal of symptomatic pain.
Bone Density
The amount of bone tissue in a specific volume of bone.
Bone Marrow
The blood-forming tissue filling the bone's cavities, composed of fat and immature and mature blood cells.
Bone Marrow Biopsy
The extraction of a bone marrow sample and a marginal amount of bone through a large needle, usually conducted through the hip.
Bone Marrow Transplant (BMT)
The procedure by which diseased or damaged bone marrow is replaced with healthy bone marrow.
Bone Mass Density
Measure of bone density.
Bone Mineral Density (BMD)
Measure of bone density, or bone strength, as reflected by the bones' calcium content.
Bone Scan
A technique that provides bone images for visualization on computer screen or film.
Booster Shot
A dosage of vaccine periodically required to refresh the immune system to better protect itself against the disease represented in the vaccine.
Borderline Personality Disorder
An illness characterized by a debilitating instability in moods, self-image, behavior and in interpersonal relationships, often disrupting familial and work roles, long-term commitments, and the individual's concept of identity.
A condition in which the legs curve outward after infancy, leaving a gap between the knees. Can be surgically corrected. Also termed genu varum and tibia vara.
Bowen Disease
An early stage of squamous cell carcinoma, a form of cancer, within the epidermis.
Radiation treatment administered by placing radioactive material directly in or on the the point at aim, most commonly a malignant tumor. When used to treat prostate cancer, brachytherapy is referred to as interstitial radiation therapy.
Brain Aneurysm
A small out-pouching resembling a berry, occurring at the base of the brain. Brain aneurysms are prone to rupture and bleed. Also see Berry Aneurysm.
Brain Biopsy
The removal of a small sample of brain tissue, utilized for diagnostic purposes.
Brain Cancer
Cancer of the brain. Primary cancerous brain tumors develop in the brain tissue, while secondary brain cancer tumors metastasize to the brain tissue from other malignant areas of the body. If brain cancer occurred from the spread of cancer originating in the stomach, the organ of cancerous origin would be named first. The individual would be said to have stomach cancer with secondary brain metastasis.
Brain Hemorrhage
Cerebral or intracerebral bleeding. A brain hemorrhage, or bleeding in the brain, may occur as a result of a tumor, stroke, aneurysm rupture, trauma or hemophilia.
Brain Tumor
A growth in the brain which can be malignant (cancerous) or benign (of no harm).
Brainstem Implant
A hearing aid that forgoes the cochlea and auditory nerves and is implanted into the brainstem, used on individuals whose auditory nerves are not functioning and thus would not gain benefit from a cochlear implant.
BRCA Mutation
Mutations of the genes BRCA1 and BRCA2, directly shown to lend to a greater propensity to develop ovarian cancer and breast cancer, in women.
Breast Aplasia
A rare condition that prevents the development of a nipple to take place.
Breast Biopsy
A procedure in which a sample of a abnormal breast growth is removed through needle or surgery, most commonly to conduct cancer diagnostics.
Breast Cancer
Cancer of the breast, most commonly detected through a self or physician-conducted examination of the breast, in a mammograph, ultrasound or biopsy. Breast cancer can take on many forms with varying likelihoods to spread. Treatment is dependent on the form and location of the malignant cells, and the health condition and age of the individual.
Breast Cancer Gene
Mutated genes that can contribute or increase the likelihood of developing breast cancer. See BRCA Mutation.
Breast Lump
A localized swelling, bulge, knot, protuberance or bump found or felt in the breast, occurring at any age and in both genders. Breast lumps can be the result of a benign, treatable condition such as fibroadenoma, a cyst or infection, but all breast lumps need be examined by a physician.
Breech Birth
The delivery of a baby rear-end first. A breech birth has a greater likelihood to cause injury to the mother and/or infant, but in many cases the infant can be turned around prior to delivery through simple maneuvering.
Bright's Disease
A condition causing chronic inflammation of the blood vessels located within the kidney.
The air tubes that allow for the passing of air between the trachea and lungs.
Permanent dilatation of the bronchi, which can result in serious illness including recurrent respiratory infections and the coughing of blood.
A tiny tube within the lungs' airway system that continues out of the bronchi and connects to the alveoli.
Inflammation of the bronchioles due to viral infections such as respiratory syncytial virus (RSV),influenza or adenoviruses.
Inflammation and swelling of the bronchi, acute or chronic. Chronic bronchitis maintains symptoms for three months or two consecutive years.
Teeth grinding and gnashing.
Lymph node that is enlarged, tender and painful, usually in the groin or armpit area.
Bubonic Plague
Plague named for the characteristic symptom of swollen lymph nodes, or buboes,it produced. Plague was caused by Yershina pestis bacteria transmitted from rats to fleas to humans.
Bulimia nervosa is a psychological eating disorder marked by episodes of secretive and excessive binge eating, followed by abnormal attempts to achieve weight control. These may include purging (self-induced vomiting), excessive exercise, and abuse of laxatives or diuretics. The binging appetite of bulimia is often interjected with anorexic periods, wherein the bulimic individual becomes unable to eat.
Bulimia Susceptibility Gene
A gene used to determine an individual's susceptibility to developing bulimia. A bulimia susceptibility gene is known to be linked to chromosome 10p and another may be on chromosome 14.
Being in a state of blistering, such as when one has suffered second-degree burns.
Burn Treatment
The treatment of burns dependent on location, depth and severity.
Burn - first degree
A superficial burn; skin is red and responsive to sensation.
Burn - second degree
Like a first degree burn, the skin in an area with second degree burns is red and responsive to sensation, but blistering has formed and pain is usually greater.
Burn - third degree
Skin is so damaged that it is lifeless, white and without sensation.
Burning Mouth Syndrome
An intense burning sensation experience on the tongue, more common among supertasters, those with an over-abundance of taste and pain receptors located on their tongues, and post-menopausal women.
Inflammation of the bursa, a tiny, fluid-filled sac that serves to reduce friction between body tissues.
Bursitis of the Elbow
Inflammation of the bursa at the elbow; olecranon bursitis.
Bursitis of the Hip
Inflammation of the bursa at the hip joint.
Bursitis of the Knee
Inflammation of the bursa at the knee joint.
Bursitis of the Shoulder
Inflammation of the bursa at the shoulder joint.
An surgical operation in which a new tubular pathway is created to aid the movement of fluids and/or other substances flowing within the body.
Bypass - Cardiopulmonary
A bypass that takes place in the heart or lungs. Blood bound for the heart is diverted through a pump-oxygenator before it is returned to circulation, performing the functions of both the heart and lungs in surgery.