Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
A set of multiple-choice questions and answers related to fluoroscopy. It covers topics such as the history of fluoroscopy, image intensification, visual acuity, and flat panel detectors. The questions are designed to test understanding of key concepts and principles in fluoroscopy, making it a useful resource for students and professionals in radiology and medical imaging. It includes questions about image intensifiers, radiation safety, and digital fluoroscopy techniques, offering a comprehensive review of the subject.
Typology: Exams
1 / 58
This page cannot be seen from the preview
Don't miss anything!
Fluoroscopy was developed so that radiologists could view _____ images. a. static b. dynamic c. magnified d. darkened b. dynamic Who discovered the first fluoroscope? a. Albert Einstein b. Wilhelm Roentgen c. Isaac Newton d. Thomas Edison d. Thomas Edison What is the milliamperage used during fluoroscopy? a. ≤ 100 mA b. ≤ 50 mA c. ≤ 5 mA d. ≤ 1 mA
c. ≤ 5 mA The image intensifier improved fluoroscopy by increasing image_____. a. brightness b. resolution c. magnification d. contrast a. brightness Image intensified fluoroscopy is performed at illumination levels similar to _____. a. star gazing b. darkened theaters c. night driving d. radiographed viewing d. radiographed viewing Visual acuity in the eye is greatest at the ___________, where ________ are concentrated. a. retinal periphery, cones b .fovea centralis, cones c. retinal periphery, rods d. fovea centralis, rods b .fovea centralis, cones
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. input phosphor The output phosphor of the image intensifier is composed of __________. a. cesium iodide b. antimony c. zinc cadmium sulfide d. graphite c. zinc cadmium sulfide The input phosphor converts _________ to _________. a. x-rays, electrons b. light, electrons c. electrons, light d. x-rays, light d. x-rays, light
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. photocathode The number of light photons emitted within the image intensifier is _________ to the amount of x-ray photons exiting the patient. a. equal b. unrelated c. inversely proportional d. directly proportional d. directly proportional The kinetic energy of photoelectrons in the image intensifier is greatly increased by the a. mAs of the exposure b. potential difference across the tube c. cesium iodide at the input phosphor d. zinc cadmium sulfide at the output phosphor
b. brightness gain The ratio of x-rays incident on the input phosphor to light photons exiting the output phosphor is called ___________ gain. a. magnification b. minification c. brightness d. flux d. flux 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. brightness gain An image intensifier tube is identified by the diameter of its a. input phosphor b. glass housing
c. output phosphor d. focusing lenses a. input phosphor Brightness gain is typically in the range of ____________. a. 5 0 - 75 b. 100-1, c. 3,000-4, d. 5,000-30, d. 5,000-30, Fluoroscopy for an air contrast barium enema is generally done at ____ kVp. a. 65- 75 b. 70- 80 c. 80- 90 d. 100- 110 c. 80- 90 Viewing the fluoroscopic image in magnification mode increases______. a. contrast resolution b. spatial resolution
c. vignetting d. distortion c. vignetting Compared to the image intensification systems, flat panel detectors produce lower-quality images with a higher signal-to-noise ratio when used at lower exposure settings, such as those required in continuous fluoroscopy. a. True b. False b. False Flat panel detectors contain amorphous silicon thin-film transistors (TFT). a. True b. False a. True The image intensification artifact that has an unequal magnification and a curving, or warping, of the image, predominately at the periphery is known as a. vignetting b. pincushion distortion c. lag d. veiling glare
b. pincushion distortion The video camera tube converts the dynamic optical image into a standard video signal. a. True b. False a. True The ______ converts the voltage signal from the video camera tube to charge coupled device (CCD) into visible image. a. Image intensifier b. Signal transfer coil c. Focusing coils d. video monitor d. video monitor ______ transfer and distribute light from the output window from the image intensifier to image viewer/recording device. a. input phosphor b. storage capacitors c. digitization chambers d. optic coupling devices d. optic coupling devices
a. Ture b. False a. True The cathode-grid assembly in the video tube often is referred to as the ______. a. signal originator b. electron gun c. anode d. signal receptor b. electron gun What is the brightness gain for a 17 cm image intensifier tube with a flux gain of 120 and a 2.5 cm output phosphor? a. 5520 b. 816 c. 4600 d. 612 a. 5520 The ability to perceive fine detail is called a. visual acuity b. photopic vision
c. scotopic vision d. line pairs per inch e. all of the above a. visual acuity When the "boost position" (high level control) is provided on mobile fluoroscopic equipment, the correct way to employ this option is to first use the normal mode to locate the area of interest and then only use the boost position when necessary. a. True b. False a. True To aid the radiologist during fluoroscopy, most modern units will automatically change radiation levels for thicker or thinner body parts. This control is termed: a. Automatic brightness control b. Automatic exposure control c. Automatic subtraction d. None of the above a. Automatic brightness control The high level control (Boost Position) requires special continuous manual activation and an audible signal to indicate the high level control is being utilized by the fluoroscopist.
a. True b. False b. False The image intensifier should be placed as far away from the patient as possible to reduce the radiation dose to the patient, especially when using automatic brightness control fluoroscopic equipment. a. True b. False b. False The amount of time it takes for the brain to interpret what the eye is "seeing" is called INTEGRATION TIME a. True b. False a. True The predetermined time limit on the cumulative manual-set timer a. shall not exceed 10 minutes b. should not exceed 10 minutes c. shall not exceed five minutes
d. should not exceed five minutes e. More than one above c. shall not exceed five minutes What charge occurs when the kilovoltage (kVp) peak is increased and the milliamperage seconds (mAs) is correspondingly decreased? a. Patient skin dose (entrance skin dose) increases b. Image distortion decreases (i.e.: a shorter scale of contrast) c. Patient skin dose (entrance skin dose) decreases d. Fluoroscopic image contrast is increased e. Image distortion increases d. Fluoroscopic image contrast is increased During televised image intensified fluoroscopy, permanent static images or spot films can be produced and recorded using:
c. pixel size d. Hounsfield units a. matrix size Minimum sources-to-skin distance for a fixed radiographic system is: a. 15'' b. 13" c. 12" d. 14" a. 15'' Scatter dose rate is higher near the area where the x-ray beam enters the patient. a. True b. False a. True The following are factors that contribute to the patient entrance skin exposure (ESE): a. Collimation b. Source-to-skin entrance c. location of image intensifier d. all of the above
d. all of the above The main source of radiation for staff during a fluoroscopy procedure is scatter radiation from the patient. a. True b. False a. True The patient entrance skin exposure is lower when the fluoroscopic x-ray tube is _____ from the tabletop and the image intensifier is _____ to the patient. a. farther, closer b. farther, farther c. closer, farther d. closer, closer a. farther, closer Which of the following are factors affecting staff dose? a. Relative position with respect to patient b. X-ray tube position c. Effective use of shielding d. All of the above d. All of the above
