I - Glossary of Terms

Glossary of terms index - A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

I - Glossary of Terms

-iasis	(-i'a-sis) Suffix denoting morbid or diseased condition; as elephantiasis, nephrolithiasis, dracontiasis.
iatrogenic	Resulting from the activity of physicians.
idio-	(id'i-o-) Prefix combining form denoting self-produced; as idiopathic, self-originated, of unknown cause.
ileac	(il-e-ak) Pertaining to ileum or to ileus; cf. iliac.
ileo-	(il'e-o-) Prefix denoting some relation to ileum; as ileocolic, ileocecal, ileotomy.
ileocecal valve	(il´´e-o-se´kal) a modification of the mucosa at the junction of the small and large intestine that forms a one-way passage and prevents the backflow of food materials.
ileum	(il´e-um) The terminal portion of the small intestine between the jejunum and cecum.
ileus	(il'e-us) Condition caused by intestinal obstruction, marked by severe pain in and distention of abdomen.
iliac	(il'e-ak) Of or pertaining to ilium; cf. ileac.
iliac fossa	groin area (see inguinal region)
ilium	(ile-um) The components of the hip bone, the ilium, ischium and pubis, meet in the centre of the acetabulum, the three parts fusing at about 16 yrs of age.
im- , in-	Prefixes meaning in, within, or into, as in immersion, injection; also, not, non-, un-, as in imbalance, inactive, incurable.
image detail	The sharpness of small structures on the radiograph.
image-forming x-ray	An X-ray that exits from the patient and enters the image receptor.
image intensifier	An electronic vacuum tube that amplifies a fluoroscopic image to reduce patient dose.
image matrix	A layout of cells in rows and columns.
image noise	The deterioration of the radiographic image.
image receptor (IR)	The medium that transforms the X-ray beam into a visible image; radiographic film or a phosphorescent screen.
image receptor contrast	Contrast that is inherent in the film and is influenced by processing of the film. See also subject contrast.
impacted	(im-pak'ted) Firmly wedged or lodged in position; forcibly driven together, as two ends of a bone in an impacted fracture.
improper fraction	A fraction in which the quotient is greater than 1.
incipient	(in-sip'e-ent) Beginning to exist; commencing; as the incipient or initial stage of a disease.
incisura	(in"si-su-rah) Notch or cleft; deep indentation.
incisure	(in-sizh'ur) Notch; cut or gash.
incontinence	(in-kon'ti-nens) Inability of any of organs to restrain a natural evacuation; involuntary discharges; as incontinence of urine or feces.
incus	(ing´kus) the middle of three auditory ossicles within the middle-ear chamber; commonly called the anvil.
indirect effect	The effect of radiation that results from the production of free radicals produced by the interaction of radiation with water.
indolent	Causing little or no pain; slow to heal.
induction	The process of making ferromagnetic material magnetic.
induction motor	An electric motor in which the rotor is a series of wire loops but the external magnetic field is supplied by several fixed electromagnets called stators.
induration	(in"du-rd'shun) Hardening or hardened tissue resulting from inflammation or congestion.
inertia	The property of matter that resists change in motion or at rest.
infarct	(in'farkt) Circumscribed area of necrosis of tissue, resulting from obstruction of local blood supply by an embolus or a thrombus.
infarction	Death of tissue because of interruption of the normal blood supply.
infection	(in-fek'shun) Communication of disease germs to body tissues by any means.
infectious	(infek'shus) Contaminated or charged with disease germs; readily communicable by infection but not necessarily contagious; cf. contagious.
inferior	(in-fer'ier). Situated lower or nearer to bottom or base; below.
inferior vena cava	(in-fer'ier ve´na ka´va) a large systemic vein that collects blood from the body regions inferior to the level of the heart and returns it to the right atrium.
inferosuperior	(in'fer-o-su-per'i-er) Directed or extending from below upward; caudocranial.
infiltration	(in"fil-tra'shun) Filtering into or penetration of tissues by a substance not normal to them.
inflammation	(in"fla-ma'shun). Morbid condition produced in tissues by an irritant; natural reaction to irritation wherein plasma and blood cells are excluded at site of infection or injury in attempt to heal damage; it is manifested by redness, swelling, and pain.
infra-	(in'frah-) Prefix meaning below; as infraorbital, situated below orbit.
infraorbitomeatal line	(in"frah-orbit-o-me-a'tal) Also known as Virchow's plane (ve'koz). A line that extends from center of inferior orbital margin to center of tragus and that is used in radiography for adjustment of base of cranium. Because this line closely parallels anthropologic base line, it is frequently denoted by this and other terms applied to anthropologic base line.
infrared light	A light consisting of photons with wavelengths longer than those of visible light but shorter than those of microwaves.
infrared radiation	Electromagnetic radiation just lower in energy than visible light, with a wavelength in the range of 0.7 to 1000 p.m.
infundibula	Thin passages connecting the calyces to the renal pelvis
infundibulum	(in´´fun-dib´u-lum) latin = funnel, the stalk that attaches the pituitary gland to the hypothalamus of the brain.
infusion	(in-filzhun) Process of introducing a solution into a vessel or a hollow viscus by gravity pressure; cf. injection, instillation, insufflation.
ingest	(in-jest'). To take in for digestion; to eat; to take anything by mouth.
ingestion	(in-jes´chun) the process of taking food or liquid into the body by way of the oral cavity.
inguinal	(ing'gui-nal) Of or pertaining to region of inguen or groin, region between abdomen and thigh.
inguinal region	(ing'gui-nal)) Pertaining to the groin region. (see iliac fossa)
inguinal canal	(ing'gui-nal) The circular passageway in the abdominal wall through which a testis descends into the scrotum.
inherent filtration	The filtration of useful X-ray beams provided by the permanently installed components of an X-ray tube housing assembly and the glass window of an X-ray tube.
inion	(in'i-on) External occipital protuberence.
initiation time	The time required to start an exposure.
injection	(in-jek'shun). Forcible introduction, usually by syringe, of a liquid, gas, or other material into a part of body, a vessel, a cavity, an organ, or subcutaneous tissue; cf. infusion, instillation, insufflation.
inorganic	(in"or-gan'ik) Not organic in origin; pertaining to or composed of substances other than animal or vegetable; inanimate matter; as inorganic elements.
input	The process of transferring information into primary memory.
insertion	the more movable attachment of a muscle, usually more distal. (see attachment)
insidious	Developing in a slow or not apparent manner; more dangerous than seems evident, as in an insidious disease.
inspiration	(in´´spi-ra´shun) the act of breathing air into the alveoli of the lungs; also called inhalation.
inspissated	(in-spis'a-ted) Thickened by evaporation or by absorption of fluid content; as inspissated pus.
instillation	(in"stil-Ia-shun). To drop in; process of introducing a liquid into a cavity drop by drop; cf. infusion, injection, insufflation.
insufflation	(in"su-fla'shun). Act of blowing air or gas (or a powder or vapor) into a cavity of body, as into colon for double-contrast enema; cf. infusion, injection, instillation.
insula	(in´suu-la) a deep, paired cerebral lobe.
insulator	A material that inhibits the flow of electrons in a conductor or in heat transfer.
integrate mode	A function of an instrument designed to measure the total accumulated intensity of radiation over a period of time.
integument	(in-teg´yoo-ment) the skin; the largest organ of the body.
intensification factor (IF)	The ratio of exposure without screens to that with screens to produce the same optical density.
intensifying screen	A sensitive phosphor that converts X-rays to light to shorten exposure time and reduce patient dose.
intensity	The total energy passing through a unit area per unit time.
intensity profile	The projection formed by the intensity of radiation detected according to the attenuation pattern.
inter-	(in'ter-) Prefix signifying between; as interlobar, situated between two lobes.
intercellular substance	(in´´ter-sel´yuu-lar) the matrix or material between cells that largely determines tissue types.
intercostal	(in"ter-kos'tal) Pertaining to or situated in spaces between ribs.
interface	The boundary between the shadows of two juxtaposed structures or tissues of different texture or opacity.
internal (deep)	Toward the center, away from the surface of the body.
internal ear	The innermost portion or chamber of the ear, containing the cochlea and the vestibular organs.
internally deposited radionuclide	A naturally occurring radionuclide in the human body.
International System of Units (SI)	Standard system of units based on the meter, kilogram, and second; it has been adopted by all countries and is used in all branches of science.
interosseous membrane	A fiberous membrane attaching bones in a fiberous joint of variable flexibility e.g. intermediate radioulnar joint, inferior tibiofibular joint (see syndesmoses)
interpediculate	(in"ter-pe-dik'u-late). Of or pertaining to space between pedicles of neural arch.
interphase	The period of growth of the cell between divisions.
interpolation	The estimation of a value between two known values.
interpupillary line	(in"ter-pu'pi-lere). Imaginary line passing through pupils of eyes; used in radiography in adjustment of head in an exact lateral position.
interspace material	The sections of radiolucent material in a grid.
interstice	(in-ter'stis) Small gap or space in a tissue; an interval.
interstitial	(inter-stish'al) Of or pertaining to spaces, or interstices, of a tissue.
interstitium	A continuum of loose connective tissue throughout the lung comprising three subdivisions: The bronchovascular interstitium (surrounding the pulmonary arteries, veins, and bronchi) The parenchymal interstitium (between the alveolar and capillary basement membranes) The subpleural interstitium (beneath the visceral pleural and within interlobular septa).
intervertebral disc	(in´´ter-ver´tue-bral) A pad of fibrocartilage located between the bodies of adjacent vertebrae. (see annulus fibrosus, neucleus pulposus)
interrogation time	Time during which the signal from an image detector is sampled.
interstitial	Referring to the area between cells.
intestinal crypt	A simple tubular digestive gland opening onto the surface of the intestinal mucosa that secretes digestive enzymes; also called the crypt of lieberkühn.
intima	Innermost layer of an organ or blood vessel.
intra-	(in'trah-) Prefix meaning within or into; as intralobar, within a lobe, and intravenous, injected into a vein.
intraluminal	Within the empty space (lumen) of a hollow viscus.
intramembranous ossification	(see membranous bone.)
intramural	Within the wall of an organ.
intrapleural space	(in´´tra-ploor´al) an actual or potential space between the visceral pleural membrane covering the lungs and the somatic pleural membrane lining the thoracic wall.
intrinsic	(in-trin'sik) Situated or originating entirely within an organ or part; opposite of extrinsic.
invaginate	to fold inwards or sheathe.
invaginated	(in-varj'i-nated). Condition of being drawn inward to become ensheathed, as a covering membrane turning backward to form a double-walled cavity.
Inverse square law	Law stating that the intensity of the radiation at a location is inversely proportional to the square of its distance from the source of radiation.
inverse voltage	Current flowing from the anode to the cathode.
inversion	(in-ver´zhun) a movement of the foot in which the sole is turned inward.
invert	(in'vert). To turn inward; as to invert foot.
inverter	High-speed switches that convert direct current into a series of square pulses.
invitro	(in ve´tro) occurring outside the body, in a test tube or other artificial environment.
invivo	(in ve´vo) occurring within the body, In the living cell.
involuntary	(in-vol'un-ter"e). Movement not under control of the will, as that of cardiac, gastrointestinal, and other involuntary muscles.
ion	An atom with too many or too few electrons; an electrically charged particle.
ion chamber	An instrument that detects and measures the radiation intensity in areas outside of protective barriers.
ionic bonds	A bonding that occurs because of an electrostatic force between ions.
ionisation	The removal of an orbital electron from an atom.
ionisation chamber	A device for measuring exposure by collecting the electrical charge carried by the ions produced in a finite air volume by the incident radiation.
ionisation potential	The amount of energy (34 eV) necessary to ionize tissue atoms.
ionised	Referring to an atom that has an extra electron or has had an electron removed.
ionising radiation	Radiation capable of ionisation. High-energy electromagnetic radiation that produces ions as it passes through matter e.g. X-rays, gamma rays, and some energies of ultraviolet radiation. On average, 33 eV is required to ionise a water molecule.
ion pair	Two oppositely charged particles.
ipsilateral	(ip´´si-lat´er-al) on the same side (as opposed to contralateral).
iris	(i´ris) the pigmented portion of the vascular tunic of the eye that surrounds the pupil and regulates its diameter.
irradiated	Referring to matter that intercepts radiation and absorbs part or all of it; exposed.
ischemia	(i-ske´me-a) A rate of blood flow to an organ that is inadequate to supply sufficient oxygen and maintain aerobic respiration in that organ.
ischium	the components of the hip bone, the ilium, ischium and pubis, meet in the centre of the acetabulum, the three parts fusing at about 16 yrs of age
islets of Langerhans	(i´letz of lang´er-hanz) See pancreatic islets.
isobars	Atoms having the same number of nucleons but different numbers of protons and neutrons
isochromatid	A fragment in a chromosome aberration.
isomers	Atoms having the same number of protons and neutrons but a different nuclear energy state.
isotones	Atoms having the same number of neutrons.
isotopes	Atoms that have the same number of protons but a different number of neutrons.
isotropic	Equal intensity in all directions; having the same properties in all directions.
isthmus	(is´mus) Greek isthmos = a narrow passage, a narrow neck or portion of tissue connecting two structures, eg isthmus of thyroid
-itis	(I'tis) Suffix signifying inflammation of specified part; as arthritis, appendicitis, bronchitis.

Glossary of terms index - A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


◄ .....Go back to the general radiography homepage