Diagnostic Tests Flashcards
Xrays are sometimes referred to as _______ rays, which are named after their discoverer, Wilhelm Konrad Roentgen.
Roentgen rays.
X-ray films are produced by exposing __________ to the __________ from an ___________.
X-ray films are produced by exposingsensitized filmto theenergy wavesfrom anx-ray generatoror acathode ray tube
When part of a body is positioned between an x-ray source and sensitized film, the result is a _______ of that body part.
an image or a shadow
_________ appear in various shades of black, white and gray.
Radiographs
Ther areas where x-rays _________ appear black.
Ther areas where x-rays strike the film directly appear black.
The areas where the x-rays are ________ appear in shades of white or gray.
The areas where the x-rays are blocked by tissues of varying densitiesappear in shades of white or gray.
_______ appears on the film as a shade of gray, and _____ appears as a shade of white.
Soft tissue - less denseappears on the film as a shade of gray, and bone - relatively denseappears as a shade of white.
What are 6 characteristics of X-rays?
X-rays Cause exposure of a photographic plate
Penetratedifferent substances Invisibility Travel instraight lines
Scatteringof radiation Ionization
EPISSIExposure, penetration, invisibility, straight lines, scattering, ionization
A _______ usually takes the films while a _______ interprets and performs intervening procedures.
A technicianusually takes the films while a radiologist interprets and performs intervening procedures.
A _______ is a medical doctor with years of special training in medical imaging.
Radiologist
When the photographic plate is placed in front of x-ray beams, the x-rays have the ability to change the plate from ____ to ____.
When the photographic plate is placed in front of x-ray beams, the x-rays have the ability to change the plate from silver to black.
T or F. X-rays oass through body substances with varying ease.
True.
_____ is the least dense substance and exhibits the greatest transmission
Air.
What is the least dense and most dense between fat, water (soft tissue) and metal (bone)?
Fat is theleast densebut isdenser than air. Water or soft tissue is denser than fat. Metal or bone is the most dense.Least dense to most dense:Fat > water > metal
______ is the most dense and transmits the least.
Metal orboneis the most dense and transmits the least.
What does it mean when a substance absorbs x-rays?
The x-rays arestoppedby the substance.
T or F. If the x-rays are absorbed by the denser body substance (e.g. bones), they don’t reach the photographic plate held behind the patient, and white areas ar left in the x-ray film.
True.
_________ structures permit the passage of most x-rays and appear black on x-ray film.
Radiolucent
_______ structures obstruct the passage of x-rays and appear white on x-ray film.
Radiopaque.
T or F. X-rays can be detected by sight, sound, or touch.
False.
Workers exposed to x-rays must wear a ________ to detect and record the amount of radiation to which they have been exposed.
A film badge.
X-ray characteristic of travelling straight lines allows for the formation of ______ shadow images on the x-ray plates.
X-ray characteristic of travelling straight lines allows for the formation of precise shadow images on the x-ray plates.
T or F. Straight x-ray beams allows beams to be directed accurately at a tissue site during radiotherapy.
True.
___________ occurs when x-rays come in contact with any material.
Scattering.
Greater scatter occurs with _______ objects and fewer scatter occurs with __________ substances.
Greater scatter occurs withdenseobjects and fewer scatter occurs withradiolucentsubstances.
Scatter can ______ images and ______ areas of film that otherwise would be in shadow. To eliminate this, a _____ is placed in front of the film to absorbed scattered radiation before it strikes the x-ray film.
Scatter can blurimages and exposeareas of film that otherwise would be in shadow. To eliminate this, a grid is placed in front of the film to absorbed scattered radiation before it strikes the x-ray film.
X-rays ____ substances through which they pass. In radiation therapy, this effect helps kill cancerous cells. In several doses, this effect can affect normal body cells which leads to tissue damage and malignant changes.
Ionize.
T or F. When a disease isn’t diagnosed by using plain x-ray filming, then special radiological diagnostic procedures are performed.
True.
A _________ is a radipaque substance used in diagnostic radiology to allow a more accurate visualization of internal body parts and tissues in contrast to their adjacent structures.
Contrast medium
T or F. Contrast media are liquids administered orally.
Partially true. Contrast media are liquids, powders, gas, air, or pill that can be administered orally, parenterally, or via enema.
How does contrast media work?
Contrast mediaopacifiesthe body part(s) under examination so the structure and functions of the organs can therefore be observed in more detail.
Give two examples of contrast media.
Barium sulfate and iodine compounds
________ is a harmless, opaque, chalkycompound available inpremixed, flavored liquid.
Barium sulfate
What are the two main types of x-ray and fluoroscopic examinations of th GI tract that barium sulfate is used for?
Upper GI series (barium swallow) Lower GI series (barium enema)
In ______ an oral ingestion of barium mixture is used to outline the esophagus, stomach, and small intestine.
Upper GI series
In _____ a barium mixture is given through an enema and outlines the colon.
Lower GI series
________ are radiopaque fluids used as contrast dye and containup to 50% of its main element.
Iodine compounds
X-ray recording ofblood vesselsand theheart chambersfollowing the injection of contrast medium through acatheterinserted into thevessel in issue.
Angiography
X-rays are taken after the dye has been injected into theaortaor into anartery in the groin
Arteriography
X-ray recording of ajointafter contrast medium injected into joint
Arthrography
X-ray recording of thebronchial tree and lungs. Instillation of a contrast medium into thebronchi via the trachea
Bronchography
X-ray recording of thebile ducts. Dye injectedintravenously, percutaneously, or orally(directed by liver into the bile ducts)
Cholangiography
X-ray recording of thegallbladder and bile ducts.Orally ingested. Radiopaque granules or tablet, IV injection
Cholecystography
Imaging ofblood vesselsin which a computersubtracts obscuring shadowsfrom the image, allowingonly vesselsto be seen.Two x-raysare taken (the first x-raywithoutcontrast).
Digital subtraction angiography (DSA)