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66 Cards in this Set
- Front
- Back
Digital imaging could only be developed after advances were made in: a) microprocessors b) semiconductor memory c) photostimulable phosphors d) Both A & C |
D |
|
Computed radiography developed in the 1970s with the use of _______ as the image receptor: a) phosphor b) selenium c) silicon d) film |
A |
|
The primary limitation of fanned beam radiography is:: a) reduced spatial resolution b) long scanning time c) low contrast resolution d) shortened dynamic range |
D |
|
If a response to radiation is expected no matter how small the dose, then that dose-response is: a) linear b) nonlinear c) nonthreshold d) threshold |
C |
|
Production of a grainy, reticulated image that cannot be corrected in digital post-processing is the result of: a) failure to use a high enough mAs setting b) failure to use a high enough kVp setting c) failure to use the correct algorithm d) failure to use the proper SID |
A Quantum mottle |
|
a) fanned x-ray beams b) linear array radiation detectors c) photostimulable phosphors d) direct capture solid-state devices |
D |
|
During CR imaging plate processing, the laser frees trapped electrons, allowing them to return to a lower energy state. This process is known as: a) photostimulated luminescence b) thermal emission c) green light phophorescence d) none of the above |
A |
|
The CR imaging plate is scanned by a(n): a) helium-neon laser beam b) ultraviolet light beam c) infrared heat source d) all of the above |
A |
|
People who had radiation treatments to their thymus gland as children, later showed excess risk for: a) bone cancers b) skin cancers c) leukemia d) thyroid cancers |
D |
|
The response of the imaging plate to ionizing radiation is: a) the characteristic curve similar to the one for film b) the D log E curve c) the H and D curves d) linear |
D |
|
Digital radiography replaces: a) the reusable detector b) grids c) traditional film d) all of the above |
C |
|
The most radiosensitive cells in the hemopoietic system of the human body are the: a) granulocytes b) erythrocytes c) lymphocytes d) platelets |
C |
|
The latent image is created by energy transfer during: a) pair-production b) coherent scattering c) photodisintegration d) photoelectric interactions |
D |
|
Studies of A-bomb indicate that leukkemia has a _______ dose-response relationship: a) nonlinear, threshold b) linear, threshold c) linear, nonthreshold d) nonlinear, nonthreshold |
C |
|
Silicon and selenium receptors are also known as: a) flat plate grids b) flat panel detectors c) conversion plates d) conversion grids |
B |
|
Silicon and selenium receptors are also known as: a) flat plate grids b) flat panel detectors c) conversion plates d) conversion grids |
B |
|
A latent image will lose about 25% of its energy in: a) 3 seconds b) 15 minutes c) 8 hours d) 24 hours |
C |
|
Scanned projection radiography was developed as a complement to: a) plain film radiography b) computerized tomography c) magnetic resonance imaging d) nuclear medicine |
B |
|
The latent image is formed on the _______ for digital radiography: a) radiographic film b) image matrix c) radiation detector d) computer screen |
C |
|
_______ is a late effect of radiation exposure: a) Erythema b) Epilation c) Cancer d) Nausea |
C |
|
The purpose of a LUT is to: a) determine the exposure index b) create the histogram c) apply a predetermined scale of contrast to the digital data set d) perform geometric processing in order to reorient the image on display |
C |
|
In digital imaging, the limiting factor in spatial resolution is the: a) pixel depth b) pixel size c) bit depth d) pixel pitch |
B |
|
What type of system uses a two-part process to convert incoming x-ray photons to an electronic signal? a) Indirect conversion b) Inverse conversion c) Direct conversion d) Proportional conversion |
A |
|
During the two-part conversion, system a(n) _______ converts light into an electronic digital signal: a) input phosphor b) scintilator c) photodetector d) output phosphor |
C |
|
Scanned projection radiography differs from conventional radiography in the lack of: a) patient motion b) spatial resolution c) contrast resolution d) scattered x-rays |
D |
|
A _______ response to radiation is directly proportional to the dose received. a) linear b) nonlinear c) curvilinear d) nonthreshold |
A |
|
Dose limits are based on a _______ dose-response relationship to radiation. a) nonlinear, nonthreshold b) linear, nonthreshold c) linear, threshold d) nonlinear, threshold |
B |
|
During the two-part conversion system, a _______ converts x-ray photons to light. a) photodector b) scintillator c) photon attractor d) cathode |
B |
|
Indirect DR uses _______ as the detector material. a) DDR b) amorphous selenium c) amorphous silicone d) CCD |
C |
|
Photoemissive materials absorb _______ and _______: a) x-ray photons, light photons b) light photons, electrons c) light photons, x-ray photons d) x-ray photons, electrons |
B |
|
The capability of an image intensifier to increase the illumination level of the image is called its: a) flux gain b) conversion factor c) brightness gain d) veiling glare |
C |
|
Indirect DR uses _______ as the detector material: a) calcium tungstate b) amorphous selenium c) amouphous silicon d) CCD |
C |
|
The _______ in the image intensifier emits electrons when it is stimulated by light photons. a) input phosphor b) output phosphor c) photocathode d) electron gun |
C |
|
Digitization of the fluoroscopic image permits: a) input phosphor b) output phosphor c) photocathode d) electron gun |
C |
|
The number of visible shades of gray in a digital image is determined by the: a) matrix size b) bit depth c) widow level d) patient thickness |
B |
|
The photocathode is composed of _______ metals: a) lead-based b) photoabsorptive c) photoemissive d) none of the above |
C |
|
The response of the imaging plate to ionizing radiation is: a) the characteristic curve similar to the one for film b) The D log E curve c) the H and D curve d) linear |
D |
|
The input screen is _______ in shape: a) oval b) elliptical c) concave d) convex |
C |
|
The number of light photons emitted within the image intensifier is _______ : a) equal b) unrelated c) inversely proportional d) directly proportional |
D |
|
Fluoroscopy is commonly used for observation of: a) the heart b) the GI tract c) a surgical procedure d) all of the above |
D |
|
Image intensified fluoroscopy is performed at illumination levels similar to: a) star gazing b) darken theaters c) night driving d) radiograph viewing |
D |
|
Automatic brightness control (ABC) maintains the brightness of the image by varying: a) monitor settings b) kVp & mA c) monitor bandwith d) all of the above |
B |
|
Each matrix pixel represents _______ in digital fluoroscopy: a) interface reflectivity b) atomic number & mass density c) proton density and spin relaxation d) radionuclide uptake |
B |
|
During CR imaging plate processing, the laser frees trapped electrons, allowing them to reduce energy state. This process is known as: a) photostimulated luminescence b) thermal emission c) green light phosphorescence d) none of the above |
A |
|
An image intensifier tube is identified by the diameter of its: a) input phosphor b) glass housing c) output phosphor d) focusing lenses |
A |
|
The output screen absorbs _______ end emits_______: a) electrons, light photons b) electrons, x-ray photons c) light photons, electrons d) light photons, x-ray photons |
A |
|
Silicon and selenium receptors are also known as: a) flat plate grids b) flat panel detectors c) conversion plates d) conversion grids |
B |
|
During fluoroscopic image intensification, the primary x-ray beam exits the patient and strikes the _______ of the image intensifier : a) input screen b) electrostatic lenses c) photocathode d) output screen |
A |
|
Fluoroscopy is a _______ radiographic examination: a) dynamic b) static c) diagnostic d) more than one of the above |
D |
|
The output phosphor of the image intensifier is composed of: a) cesium iodide b) antimony c) zinc cadmium sulfide d) graphite |
C |
|
A subject would not experience _______ following a dose high enough to cause CNS syndrome: a) hematologic syndrome b) gastrointestinal syndrome c) prodromal syndrome d) Both A & B |
D |
|
The photocathode absorbes _______ and emits _______. a) x-ray photons, light photons b) light photons, electrons, c) light photons, x-ray photons d) electrons, light photons |
B |
|
Gonadal responses to radiation have been observed at doses as low as _______ rads: a) 100 b) 50 c) 20 d) 10 |
D |
|
X-rays that exit the patient and enter the image intensifier first interact with the: a) output phosphor b) input phosphor c) photocathode d) anode |
B |
|
The time it takes to turn on the digital fluoroscpy x-ray tube and reach the selected mA and kV is called the _______ time. a) interrogation b) extinction c) radiographic d) acquisition |
A |
|
Spatial resolution is determined by the ration of _______ to ______: a) matrix size, field of view b) field of view, matrix size c) bit depth, field of view d) field of view, dynamic range |
B |
|
The input phosphor converts _______ to _______: a) x-rays, electrons b) light, electrons c) electrons, light d) x-rays, light |
D |
|
Brightness gain is typically in the range of: a) 50-75 b) 100-1000 c) 3000-4000 d) 5000-30000 |
D |
|
Electrostatic lenses are used to accelerate and focus: a) light photons b) x-ray photons c) electrons d) non of the above |
C |
|
The input screen absorbs _______ and emits _______: a) x-ray photons, light photons b) x-ray photons, electrons c) light pohotons, x-ray photons d) electrons, x-ray photons |
A |
|
What is the milliamperage used during fluoroscopy: a) < 100 mA b) < 50 mA c) < 5 mA d) <1 mA |
C |
|
The ______ is the product of the minification gain and the flux gain. a) horizontal resolution b) brightness gain c) contrast resolution d) flux gain |
B |
|
A digital fluoroscope with a charge coupled device has lower _______ and higher _______ than a conventional fluoroscope: a) light sensitivity, patient dose b) patient dose, light sensitivity c) detective quantum efficiency, maintenance d) signal-to-noise ratio, patient dose |
B |
|
During fluoroscopy, the SOD cannot be less than _____ inches. a) 10 b) 15 c) 20 d) 40 |
B |
|
A charged coupled device used in digital fluorosopy provides high: a) spatial resolution b) signal-to-noise ratio c) detective quantum efficiency d) all of the above |
D |
|
A local dose of _______ rad(s) or more can cause gonadal dysfunction a) 1 b) 5 c) 10 d) 100 |
C |