Medical terms - Letter I (page 9) | MedicalVocabulary.org

International AIDS Vaccine Initiative

See: IAVI
International normalized ratio

An international unit (IU) is an internationally accepted amount of a substance. This type of measure is used for the fat-soluble vitamins (such as vitamins A, D and E) and certain hormones, enzymes, and biologicals…
International unit (IU)

An international unit (IU) is an internationally accepted amount of a substance. This type of measure is used for the fat-soluble vitamins (such as vitamins A, D and E) and certain hormones, enzymes, and biologicals…
Interneuron

A neuron that exclusively signals another neuron
Internist

A physician who specializes in the diagnosis and medical treatment of adults. This specialty, called internal medicine, is dedicated to adult medicine. A minimum of seven years of medical school and postgraduate…
Interpersonal therapy

A form of psychotherapy in which the focus is on a patient's relationships with peers and family members and the way they see themselves. Interpersonal psychotherapy (IPT) is based on exploring issues in relationships…
Interphase

The interval in the cell cycle between two cell divisions when the individual chromosomes cannot be distinguished, interphase was once thought to be in resting phase but it is far from a time of rest for the cell. It is…
Intersex

A group of conditions sometimes referred to as disorders of sexual development (DSDs) in which there is a discrepancy between the appearance of the external genitalia and the type of internal (testes and ovaries)…
Intersexual genitalia

Genitalia that are neither typically female nor typically male. Known in clinical medicine as ambiguous genitalia. See: Ambiguous genitalia
Interstice

A small space between things, especially between things that are usually closely spaced, such as cells. Interstices are the cracks and crevices, the breaks, the gaps. The word 'interstice' comes from the Latin…
Interstitial

Pertaining to being between things, especially between things that are normally closely spaced. The word 'interstitial' comes from the Latin 'interstitium' which was derived from 'inter' meaning 'between' + 'sistere'…
Interstitial cystitis (IC)

Disease that involves inflammation or irritation of the bladder wall. This inflammation can lead to scarring and stiffening of the bladder, and even ulcerations and bleeding. Diagnosis is based on symptoms, findings on…
Interstitial radiation

Radiation therapy in which a radioactive material is placed directly into a tumor.
Interstitial radiation therapy

Radiation therapy: Radiation treatment given by placing radioactive material directly into the target, often a tumor. For example, in treating prostate cancer, radioactive seeds are implanted in the prostate gland. The…
Intertrigo

A superficial skin disorder involving any area of the body where opposing skin surfaces may touch and rub, such as the creases of the neck, the skin folds of the groin, axilla (armpit) and breasts (especially if large…
Interval malignancy

In mammography, a malignancy that becomes evident during the period between annual screening mammograms. The finding of an interval malignancy indicates that it either went undetected on the prior breast imaging scan or…
Intervening sequence

Part of a gene that is initially transcribed from the DNA into the primary RNA transcript but then is excised (removed) from it when the so-called exxon sequences on either side of it are spliced together. Intervening…
Intervention

The act of intervening, interfering or interceding with the intent of modifying the outcome. In medicine, an intervention is usually undertaken to help treat or cure a condition. For example, early intervention may help…
Interventional

Pertaining to the act of intervening, interfering or interceding with the intent of modifying the outcome. As, for example, an interventional radiologist
Interventional radiologist

A radiologist who uses image guidance methods to gain access to vessels and organs. Interventional radiologists can treat certain conditions through the skin (percutaneously) that might otherwise require surgery. The…
Interventional radiology (IR)

Rventional radiologists employ image guidance methods to gain access to the deep interstices of most organs and organ systems. Through a galaxy of techniques, they can treat certain conditions percutaneously (through…
Interventricular foramen

An opening between the lateral and third ventricles in a system of four communicating cavities within the brain that are continuous with the central canal of the spinal cord. The four ventricles consist of the two…
Interventricular septum

The stout wall separating the lower chambers (the ventricles) of the heart from one another. A hole in the interventricular septum is termed a ventricular septal defect (VSD)
Intervertebral disk

A pad of cartilage between two vertebrae that acts as a shock absorber
Intervertebral foramen

An opening between vertebrae through which nerves leave the spine and extend to other parts of the body. Also called a neural foramen
Intestinal gas

Intestinal gas: The complaint referred to as 'intestinal gas' is a common one and the discomfort can be quite significant. Everyone has gas and eliminates it by burping or passing it through the rectum. In many…
Intestinal obstruction

Blockage of the intestine by infolding (intussusception), malformation, tumor, digestive problems, a foreign body, or inflammation. Symptoms can include crampy abdominal pain, lack of ability to eliminate normal feces…
Intestinal pseudo-obstruction

Symptoms of intestinal obstruction with no sign of actual physical obstruction. This condition may be due to problems with the nerves that control intestinal muscles or other causes. Treatment depends on the cause
Intestinal villus

A tiny projection from the surface of the small intestine which helps absorb nutrients and fluids
Intestine

The long, tubelike organ in the abdomen that completes the process of digestion. It consists of the small and large intestines.
Intestine, large

The tubelike organ that completes the process of digestion, receiving material from the small intestine. It has four parts: the cecum (caecum), the appendix (vermiform appendix), the colon, and the rectum. Once the…
Intestine, small

The tubelike organ that receives the products of digestion from the stomach. It has three parts, the duodenum, the jejunum, and the ileum. The duodenum is rich in glands that produce digestive enzymes, and also receives…
Intolerance, food

Difficulty in digesting a food. Common offenders include milk products, wheat and other grains that contain gluten, and foods that tend to cause intestinal gas, such as cabbage or beans. Food intolerance is often…
Intolerance, lactose

The inability to digest lactose, a sugar component of milk and most other dairy products. Lactose is sometimes also used as an ingredient in other foods, so those with a lactase deficiency should check labels carefully…
Intra-arterial pressure

The pressure of the blood within an artery, the arterial pressure. Also called the arterial tension
Intracellular

Within a cell. In contrast to extracellular, meaning outside a cell
Intracerebral hematoma

Bleeding within the brain. Diagnosis is usually by MRI or CAT scan. Treatment is by surgery
Intracorporeal

Within the body or any structure anatomically called the corpus. For example, when men with erectile dysfunction fail intracorporeal (penile) injection therapy, sildenafil (Viagra) alone or added to the injection…
Intracranial

Within the cranium, the bony dome that houses and protects the brain. An intracranial hemorrhage is bleeding within the cranium due, for example, to a stroke or leakage of blood from an aneurysm in the brain. The…
Intracranial hematoma

A hematoma (a collection of blood) within the cranium (skull). The bleed may or may not be within the brain itself. See: Epidural hematoma; Subdural hematoma; Intracerebral hematoma.
Intractable

Unstoppable. For example, intractable diarrhea or intractable pain.
Intracytoplasmic sperm injection (ICSI)

A test-tube fertilization procedure in which a sperm is injected directly into an egg to achieve fertilization. ICSI is done for male infertility. Babies conceived by ICSI have no more major birth defects or delays in…
Intradermal

In or into the skin. An intradermal injection is given into the skin. Intradermal tests are a type of skin test. An agent (such as pollen) is injected into the skin to test the reaction to it. Intradermal tests are much…
Intradiskal electrothermal therapy

A procedure designed to relieve back pain due to damage to the disks between the spine bones. Called IDET for short. Under local anesthesia and X-ray guidance, a needle is introduced into the disk and a catheter with a…
Intraductal carcinoma

Also called ductal carcinoma in situ. See: DCIS
Intraductal papilloma

A benign, wart-like growth that occurs in breast ducts
Intraepithelial

Within the layer of cells that forms the surface or lining of an organ
Intrafallopian

A term meaning 'within the fallopian tube.' There are two fallopian tubes in female mammals, including human females. These tubes are also called oviducts. They serve as passageways connecting the egg-producing ovaries…
Intrahepatic

Within the liver.
Intramuscular (IM)

An intramuscular (IM) medication is given by needle into the muscle. This is as opposed to a medication that is given by a needle, for example, into the skin (intradermal) or just below the skin (subcutaneous) or into a…