Ultrasonography Flashcards
Echogenicity
appearance of tissues on ultrasound based on their ability to reflect sound waves; this refers to brightness of tissues being projected on a B-mode display
Anechoic
a structure lacking in internal echoes or is echo free; appears very dark to almost black
Hyperechoic
tissue of interest reflects back more intense sound waves and appears brighter than tissues surrounding it
Hypoechoic
tissue of interest reflects back less intense sound waves and appears darker than tissues surrounding it
Isoechoic
two structures that have relatively similar echogenicity toward each other
Attenuation
loss of sound wave energy as it traverses the tissue or the medium due to absorption, reflection, scattering
Reverberation
sound wave is repeatedly reflected between two highly reflective surfaces (air and probe)
Near field
area of a structure of interest closes to the probe
Far field
the area of a structure of interest that is farthest to the probe
Ultrasound=
real time imaging
Cine loop
continuous feed that allows area of interest to be viewed over a prolonged period
Ultrasound is especially useful in _ studies
cardiac
Transducer aka probe
produces sound waves then sound waves enter tissues and are reflected back to the probe, probe receives sound waves and translates info to computer
Patient prep
direct contact w/ skin required so shave, alcohol, and acoustic coupling gel on skin or probe
Typically, at least _ shades of gray are incorporated into the display of an ultrasound image
256
B mode represents
brightness
M mode represents
motion
Color doppler
track blood by using blue to show blood flow away from the transducer and red for blood flowing toward transducer
Harmonic mode
single or multiple deep, penetrating frequencies are emitted into the body along w/ harmonic overtone
Multiplanar reconstruction
reconstructing images from various planes to allow simultaneous visualization
3D mode and 4D mode only used in
human medicine
Gain
affects brightness of image
Time gain compensation (TGC) allows the user to
adjust the gain at various depth
Presets
baseline settings from manufacturer for different transducers and studies
Focal zones
when u/s beam converges more at a particular depth during the study
frequency selection
sound waves have specific frequencies that can be changed to affect penetrability of the sound waves in the tissues
Linear probe
flat contact surface (footprint)
Convex
escort or curvilinear
Phased array sector probe
crystals steered through firing time delays, usually used in cardiac studies
Matrix probe
newest type, ability to scan in diff. planes at same time to create 3D images
Volume probe
4D reconstruction capabilities, high cost, not common in vet med
Applications for u/s in bovine and ruminants
predominantly reproductive work
Equine application for u/s
sports medicine and reproduction
applications for u/s for porcine
measurement of backlit levels found in animals destined for meat production
small animal application for u/s
almost limitless
