study guide 21, 22, 23 Flashcards
- Which of the following describes portions of the image that appears brighter than normal?
Hyperechoic (page 356)
- What about images that are not as bright or are less bright then normal
hypoechoic (JL 356)
- Structure without echoes how do you describe that
anechoic (JL 356)
- A tissue or structure that has a similar echo characteristics with or without
homogeneous (JL 356)
- Tissue displaying variety of different echo characteristics
heterogeneous (JL 356)
Reverberation, comet tail, shadow, Edge shadow,
Enhancement, Focal enhancement, Mirror image, Speed error, Lobes, Side lobes and grating lobes Refraction, slice thickness, Lateral resolution, axial resolution Multipath, curved and oblique reflectors, temporal resolution artifact, spatial resolution artifact, range ambiguity artifact, Noise
(plz change if not correct)
- Artifacts are on an error on an image which one isn’t an error
- Equipment malfunction or design physics of ultrasound of error, what is this?
Causes of artifacts
- Multiple equally spaced parallel lines?
Reverberation (page 357)
- Which artifact is unrelated to the dimensions of an ultrasound pulse
Refraction artifact (page 376 question 10)
- Which artifact produces an image with an incorrect number of pulses side by side
Side lobe, grating lobe, refraction (page 375 in the box)
- Artifacts result of the replaced, all okay expect one?
I had:
artifacts result in the placement of too many echoes on the image except (MW)
Shadowing
- Which of the following does not result from multiple reflections
Enhancement (page 378 question 14)
- Two distinct reflectors are observed on an image but actually arise from a single anatomical deep image and are correct?
A mirror image (page 378 question 13)
- Two reflections from side by side which one is real and what is the normal cause for this artifact
Grating lobe artifact (page 378 question 12)
- Which artifact create one reflection on an image from two closely spaced reflectors
axial resolution (JL 370)
- When the beam dimension is greater than the reflector size what artifact may
Slice Thickness (AKA section thickness artifact or partial volume artifact), and axial resolution
- Lobes created by array transducer is called what?
grating lobes
- What methods can be used to eliminate lobe artifacts?
- Subdicing
* Apodization
- Single solid hyperechoic line parallel to the sound beam and no spaces with in the line is what artifact
Comet tail ( JL 358)
- What artifact occurs when the beam is unable to pass through a structure because of the high attenuation
shadow ( JL 359)
- Refractions at an end of circular structure can cause what artifact
Edge shadowing (JL 360) (shadowing by refraction)
- What artifact and there is too much gain in the focal zone
focal enhancement ( JL 362)
- What artifact when the medium the sound travels has a lower attenuation rate then soft tissue
speed error (JL 364) (vertical misregirstration) AKA range error artifact
- Which artifact occurs when you see reflectors at incorrect depths
Side lobe artifact (page 377 question 8)
at incorrect depths: Speed error, range ambiguity
- When propagation speed is greater than 1540 m/s reflector is placed what on the display?
too shallow?? (JL 364)
- Grating lobes are caused by what type of transducer?
array transducer
- What artifacts can be solved by lowering PRF
Range ambiguity
- Which of the following artifacts are only found with Doppler
Crosstalk/ Mirror image/ clutter (page 363)
- A grainy appearance of tissue created by interference
Speckle? (Page 374) Acoustic speckle
- Media through which ultrasound travels doesn’t propagate at 1540 m/s, assumed relationship between time and distance is invalid?
Speed error
- Propagation speed errors appear is a what?
Step-off as if the structures are “split” or “cut” (page 364)
artifacts ( JL 355)
- What are errors in imaging? One doesn’t belong
- Violation of assumptions
- Equipment malfunction or poor design
- The physics of ultrasound
- Operator error
- Causes of artifacts? one that doesn’t belong
- Doppler gain set to high
* Incident of angle is near 90% between the sound beam and the flow direction, when flow is at the beam’s focus
- Two causes for crosstalk know them!
- Color flash is also referred to as what?
??
- Wall filters are used to reject what?
Rejects the low level frequency shifts
- If the path to reflector is a different length then the returning path what artifact
Multipath (page 371)
- What produces shadowing
high attenuation (JL 359)
- Enhancement where does it appear on the image
beneath tissue with abnormally low attenuation (JL 361)
- Which transducer may have poor elevational resolution
thick transducers (JL 369) created by 1 1/2 dimensional transducer
- Avoidance of needless harm, or injury?
nonmaleficence (JL 397)
- What provides a basis for informed consent
Autonomy (JL 397)
- When can a patient revoke consent
At anytime even during a procedure or exam
- What is the first action when the sonographer enters the room
Introduces them selves
- What is the study between a worker and their environment called
Ergonomics (JL 399)
