Diagnostic imaging Flashcards
what happens to the frequency as the wavelength decreases
it decreases
which best describes ionizing electromagnetic radiation
it is characterized by the energy contained in a photon
what are not properties of x rays?
a. they can penetrate living tissue
b. they can cause some substances to fluoresce
c. they can form a homogeneous beam that travels in wavy lines
d. they are electrically neutral
c
in the diagnostic range most x rays are
bremsstrahlung radiation
which of the following controls for the contrast on the radiograph
mAs
kV
SID
RAD
kV
exposure factors for a thorax are 10 mAs and 60kV. the film density is too light and the technician wants to double the density which technique should be used
200mA 0.10 s 60kv
200*0.10= 20 mAs
to minimize magnification and pneumbra a tech should … the source image distance and… the source object distance
increase, decrease
the heel effect is going to be less noticeable with
larger film and shorter SID
a radiograph of a dog’s pelvis measures 16cm in diameter. The tech manually processed the film for the required time and temp but it is too dark. What happened?
fast-speed screens were accidentally used instead of medium speed screens
if a safelight illumination test in the darkroom involves processing the film, how should the film look if the safelight is functioning properly
evenly light-colored silver-gray
how can a tech ensure that fresh chemistry is moved onto the film
agitation
which best describes rare earth phosphors used today in intensifying screen
emit primarily in yellow-green spectrum
which is the best view of the canine elbow
craniocaudal
identify the correct peripheral borders for an elbow
one third of the radius or ulna and one third of the humerus
what are the main tenets of technician safety when taking rads
min time, max distance, max shielding
which technique will NOT help to obtain higher contrast on a film
increase the time and temperature of the chemicals
what is the main purpose of developper
reduce exposed silver halide crystals to black metallic silver
what is the key difference between computed radiography and conventional radiography
only computed radiography converts photons to metastable electrons
a vet tech must perform a UGI study of a cat. the tech presents a series of rads taken at 0, 30, and 60min and a final at 90 min
the set is incomplete- it should have included a set taken at 15 min and hourly after the 90 min if requested
in digital radiography which factor or element takes into account the frequency of appearance of a given object characteristic
histogram
Which best describes the appearance of a hyperechoic lesion on ultrasound
brighter than surrounding tissue
what is the advantage of using a 7.5MHz over a 5 MHz tranducer
detail is increased
a doppler shift is best explained as a change in… as a result of motion
frequency
which of the following occurs when the us beam interacts with a large curvilinear interface such as the diaphragm and liver border
mirror image
a technician is preparing to do an us examination of a dog’s abdomen, creating images in the transverse plane. Which image will this plane represent
ventrodorsal
which description fits the appearance of normal adrenal glands on us
hypoechoic
if a tech is preparing to take a sagittal image which way should the probe be oriented
cranial to caudal
what organ is the most difficult to image and correlate sonographic appearance with the presence or absence of disease
pancreas
which contributes to obtaining a clear sonographic image of the liver in a deep-chested dog
probe angled cranially at xiphoid process
what are the five layers of the small intestine
mucosal surface, mucosa, submucosa, muscularis, serosa
what condition would you prefer a CT to an MRI
vertebral fracture, pericardial effusion, brain disorder, large vessel thrombus
fracture
what is an accurate description of a solid lesion on us
contains many echoes which may be spread
what is the purpose of a TCG slider
controls brightness in different depths of an organ
which artifact occurs when there is minimal attenuation of the beam as it passes through a fluid-filled structure
through transmission artifact
in abdominal ultrasonography in what two planes are the organs scanned
sagittal and transverse
the normal size and shape of a cat adrenal gland is
4mm oval
which organ is most associated with acoustic shadowing and reverberation artifact
colon
which substance creates the greatest barrier to sound transmission
bone
what is the best term for loss of intensity of the us beam as it travels through tissue
attenuation
oms with nuclei that undergo radiation decay are known as
radionuclides
