balloon tamponade A procedure in which a balloon is inflated within the esophagus or stomach, to apply pressure on bleeding blood vessels, compress the vessels, and stop the bleeding. It is used in the treatment of bleeding veins in the esophagus (esophageal varices) and stomach. Also known as esophagogastric tamponade.
balloon angioplasty Coronary angioplasty that is accomplished by using a balloon-tipped catheter inserted through an artery in the groin or arm, to enlarge a narrowing in a coronary artery. Angioplasty is commonly successful in opening coronary arteries. Recurrent narrowing at the site of balloon inflation can still develop following successful coronary angioplasty. See also coronary…
ball-and-socket joint A joint in which the round end of a bone fits into the cavity of another bone. The hip joint is a ball-and-socket joint.
baldness Lack or loss of hair on the scalp. Also known as alopecia. There are many types of baldness, each with a different cause. Baldness may be localized to the front and top of the head, as in the very common type of male-pattern baldness; baldness may be patchy, a condition called alopecia areata; or…
balanoposthitis Inflammation of both the glans penis and foreskin. An uncircumcised boy should be taught to clean his penis with care to prevent infection and inflammation of the foreskin and the glans. Cleaning of the penis is done by gently retracting the foreskin, only to the point where resistance is met. Full retraction of the…
balanitis, circinate A skin inflammation around the penis in males with Reiter syndrome. With circinate balanitis, the skin around the shaft and tip of the penis can become inflamed and scaly. Cortisone creams can be used as treatment. See also balanitis; keratodermia blennorrhagicum; Reiter syndrome.
balanitis Inflammation of the rounded head (the glans) of the penis. Inflammation of the foreskin is called posthitis. In the uncircumcised male, balanitis and posthitis generally occur together as balanoposthitis: inflammation of both the glans and foreskin.
Baker cyst A swelling in the space behind the knee (the popliteal space) that is composed of a membrane-lined sac filled with synovial fluid that has escaped from the joint. Also known as synovial cyst of the popliteal space.
bag of waters The amniotic sac and amniotic fluid.
bacterium Singular of bacteria. See also bacteria.
bacteriostatic Capable of inhibiting the growth or reproduction of bacteria. See also bacteriocidal.
bacteriophage A virus that lives within a bacterium, replicating itself and eventually destroying the bacterial cell. Bacteriophages have been very helpful in the study of bacterial and molecular genetics. They are sometimes simply called phages.