RTE 1401 CORRECT EXAMS ANSWERS AND
QUESTIONS SET A+
✔✔Computer Radiography (CR) - ✔✔cassette-based way of capturing an XR
✔✔Digital (Direct) Radiography - ✔✔cassette-less, no processing necessary of XR
✔✔CR image terms - ✔✔Storage Phosphor Screen (SPS), Photostimulable Phosphors
(PSP), Photomultiplier Tube (PMT), Analog-to-Digital Converter (ADC)
✔✔Storage Phosphor Screen (SPS) - ✔✔screen inside of CR image receptor
✔✔Photostimulable Phosphor - ✔✔on the SPS and made of barium flourohalides,
bromides & iodides with europium activators
-holds latent image
✔✔Photostimulable Luminescence (PSL) - ✔✔action of the laser stimulating the PSPs
to release their excess energy in the form of visible light
✔✔Photomultiplier Tube (PMT) - ✔✔collects and amplifies light and converts it to an
electrical signal (made of e-)
✔✔Analog-to-Digital Converter (ADC) - ✔✔converts electrical signal to a digital imaging
matrix for display on a soft- copy monitor
✔✔CR image acquisition (4 steps) - ✔✔expose
stimulate
read
erase
✔✔Step 1: Expose - ✔✔SPS exposed to X-ray: PSP absorbs XR energy
✔✔Step 2: stimulate - ✔✔a helium-neon laser scans the SPS and stimulates the PSP to
release the stored energy as light (PSL process)
, ✔✔step 3: read - ✔✔PMT collects light from laser, measures and intensifies it, then
converts it to electrical signal which is sent to ADC for digital conversion
✔✔step 4: erase - ✔✔SPS is exposed to intense white light which sends all electrons
back to their ground state
✔✔phosphorescence - ✔✔delayed emission of light
✔✔fluorescence - ✔✔immediate light emission
✔✔primary influences of scatter production - ✔✔kVp, amount of irradiated tissue
✔✔How does kVp effect scatter? - ✔✔kVp increases scatter.
higher kVp= more scatter (Compton interactions)
✔✔What are ways to reduce the amount of scatter to irradiated tissue? - ✔✔Collimation
and compression
✔✔collimation - ✔✔use of collimators to reduce or increase the field size to be radiated
✔✔How does collimation effect scatter? - ✔✔more collimation (small field size)= less
scatter
✔✔How does compression effect scatter? - ✔✔reduces the amount of scatter
✔✔2 kinds of compression tactics in reducing scatter PRODUCTION - ✔✔compression
bands and patient position
✔✔How should the patient lay when using compression to reduce scatter production? -
✔✔patient should lay prone instead of supine
✔✔types of beam restricting devices - ✔✔aperture diaphragm, cones and cylinders,
collimators, positive beam-limiting device (PBL)
✔✔aperture diaphragm - ✔✔beam- restricting device that is a flat sheet of metal with a
hole cut out
✔✔cones and cylinders - ✔✔beam-restricting device used to absorb x-rays
-used in dentist offices
✔✔collimators - ✔✔2 pairs of lead shutters that can be adjusted to a desired field size
QUESTIONS SET A+
✔✔Computer Radiography (CR) - ✔✔cassette-based way of capturing an XR
✔✔Digital (Direct) Radiography - ✔✔cassette-less, no processing necessary of XR
✔✔CR image terms - ✔✔Storage Phosphor Screen (SPS), Photostimulable Phosphors
(PSP), Photomultiplier Tube (PMT), Analog-to-Digital Converter (ADC)
✔✔Storage Phosphor Screen (SPS) - ✔✔screen inside of CR image receptor
✔✔Photostimulable Phosphor - ✔✔on the SPS and made of barium flourohalides,
bromides & iodides with europium activators
-holds latent image
✔✔Photostimulable Luminescence (PSL) - ✔✔action of the laser stimulating the PSPs
to release their excess energy in the form of visible light
✔✔Photomultiplier Tube (PMT) - ✔✔collects and amplifies light and converts it to an
electrical signal (made of e-)
✔✔Analog-to-Digital Converter (ADC) - ✔✔converts electrical signal to a digital imaging
matrix for display on a soft- copy monitor
✔✔CR image acquisition (4 steps) - ✔✔expose
stimulate
read
erase
✔✔Step 1: Expose - ✔✔SPS exposed to X-ray: PSP absorbs XR energy
✔✔Step 2: stimulate - ✔✔a helium-neon laser scans the SPS and stimulates the PSP to
release the stored energy as light (PSL process)
, ✔✔step 3: read - ✔✔PMT collects light from laser, measures and intensifies it, then
converts it to electrical signal which is sent to ADC for digital conversion
✔✔step 4: erase - ✔✔SPS is exposed to intense white light which sends all electrons
back to their ground state
✔✔phosphorescence - ✔✔delayed emission of light
✔✔fluorescence - ✔✔immediate light emission
✔✔primary influences of scatter production - ✔✔kVp, amount of irradiated tissue
✔✔How does kVp effect scatter? - ✔✔kVp increases scatter.
higher kVp= more scatter (Compton interactions)
✔✔What are ways to reduce the amount of scatter to irradiated tissue? - ✔✔Collimation
and compression
✔✔collimation - ✔✔use of collimators to reduce or increase the field size to be radiated
✔✔How does collimation effect scatter? - ✔✔more collimation (small field size)= less
scatter
✔✔How does compression effect scatter? - ✔✔reduces the amount of scatter
✔✔2 kinds of compression tactics in reducing scatter PRODUCTION - ✔✔compression
bands and patient position
✔✔How should the patient lay when using compression to reduce scatter production? -
✔✔patient should lay prone instead of supine
✔✔types of beam restricting devices - ✔✔aperture diaphragm, cones and cylinders,
collimators, positive beam-limiting device (PBL)
✔✔aperture diaphragm - ✔✔beam- restricting device that is a flat sheet of metal with a
hole cut out
✔✔cones and cylinders - ✔✔beam-restricting device used to absorb x-rays
-used in dentist offices
✔✔collimators - ✔✔2 pairs of lead shutters that can be adjusted to a desired field size
