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Ultrasound or ultrasonography is a medical imaging technique that uses high frequency sound waves and their echoes. The technique is similar to the echolocation used by bats, whales and dolphins, as well as SONAR used by submarines. In ultrasound, the following events happen: The ultrasound machine transmits high-frequency (1 to 5 megahertz) sound pulses into your body using a probe. The sound waves travel into your body and hit a boundary between tissues (e.g. between fluid and soft tissue, soft tissue and bone). Some of the sound waves get reflected back to the probe, while some travel on further until they reach another boundary and get reflected. The reflected waves are picked up by the probe and relayed to the machine. The machine calculates the distance from the probe to the tissue or organ (boundaries) using the speed of sound in tissue (5,005 ft/s or1,540 m/s) and the time of the each echo's return (usually on the order of millionths of a second). The machine displays the distances and intensities of the echoes on the screen, forming a two dimensional image like the one shown below.
Pulmonary fibrosis is a condition in which the tissue deep in your lungs becomes scarred over time. This tissue gets thick and stiff. That makes it hard for you to catch your breath, and your blood may not get enough oxygen. Causes of pulmonary fibrosis include environmental pollutants, some medicines, some connective tissue diseases, and interstitial lung disease. Interstitial lung disease is the name for a large group of diseases that inflame or scar the lungs. In most cases, the cause cannot be found. This is called idiopathic pulmonary fibrosis
Sodium levels are tightly controlled in a healthy individual by regulation of urine concentration and an intact thirst mechanism. Hypernatremia (defined as a serum sodium level >145 mEq/L) is rare in patients with preserved thirst mechanism. When hypernatremia does occur, it is associated with a high mortality rate (>50% in most studies). Given this high mortality rate, the emergency physician must be able to recognize and treat this condition. This article discusses the patients in whom hypernatremia should be suspected and how to initiate workup and administer appropriate treatment. In general, hypernatremia can be caused by derangement of the thirst response or altered behavioral response thereto (primarily psychiatric patients, and elderly patients who are institutionalized), impaired renal concentrating mechanism (diabetes insipidus [DI]) secondary to kidney pathology (nephrogenic DI) or difficulty with the neurohormonal control of this concentrating mechanism (central DI), or by losses of free water from other sources.
Priapism is a prolonged erection of the penis. The persistent erection continues hours beyond or isn't caused by sexual stimulation. Priapism is usually painful. Although priapism is an uncommon condition overall, it occurs commonly in certain groups, such as people who have sickle cell anemia. Prompt treatment for priapism is usually needed to prevent tissue damage that could result in the inability to get or maintain an erection (erectile dysfunction). Priapism is most common in men in their 30s.
Penile implants are devices placed inside the penis to allow men with erectile dysfunction (ED) to get an erection. Penile implants are typically recommended after other treatments for ED fail. There are two main types of penile implants, semirigid and inflatable.
This video: Patent ductus arteriosus (PDA) is a persistent opening between two major blood vessels leading from the heart. The opening, called the ductus arteriosus, is a normal part of a baby's circulatory system before birth that usually closes shortly after birth. If it remains open, however, it's called a patent ductus arteriosus. A small patent ductus arteriosus often doesn't cause problems and might never need treatment. However, a large patent ductus arteriosus left untreated can allow poorly oxygenated blood to flow in the wrong direction, weakening the heart muscle and causing heart failure and other complications. Treatment options for a patent ductus arteriosus include monitoring, medications and closure by cardiac catheterization or surgery.
What is the spleen and what causes an enlarged spleen (splenomegaly)? The spleen sits under your rib cage in the upper left part of your abdomen toward your back. It is an organ that is part of the lymph system and works as a drainage network that defends your body against infection. White blood cells produced in the spleen engulf bacteria, dead tissue, and foreign matter, removing them from the blood as blood passes through it. The spleen also maintains healthy red and white blood cells and platelets; platelets help your blood clot. The spleen filters blood, removing abnormal blood cells from the bloodstream. A spleen is normally about the size of your fist. A doctor usually can't feel it during an exam. But diseases can cause it to swell and become many times its normal size. Because the spleen is involved in many functions, many conditions may affect it.
our uterus (or womb) is normally held in place inside your pelvis with various muscles, tissue, and ligaments. Because of pregnancy, childbirth or difficult labor and delivery, in some women these muscles weaken. Also, as a woman ages and with a natural loss of the hormone estrogen, her uterus can drop into the vaginal canal, causing the condition known as a prolapsed uterus.
A Pap smear (also called a Pap test) is a screening procedure for cervical cancer. It tests for the presence of precancerous or cancerous cells on the cervix, the opening of the uterus. It's named after the doctor who determined that this was a useful way to detect signs of cervical cancer.