Dsvt Ch. 6 Review

Front 1

Who regulates ultrasound equipment

Back 1

FDA

Front 2

What is needed to perform an ultrasound on a patient

Back 2

Doctor's order

Front 3

Which type of tissue is more tolerant of the temperature increased caused by ultrasound

Back 3

Adult tissues are more tolerant then fetal or neonatal tissue

Front 4

Have biofix ever been identified at diagnostic indices?

Back 4

No confirmed significant biological effect in mammalian in tissue for exposure below.

100 mW/cm2

Front 5

While scanning a fetus, you notice your image is too dark overall. What would you do to correct it and why?

Back 5

Increase overall gain to Brighton entire image.

Gain does not increase fetal exposure to energy

Front 6

Which acoustic output index is an indicator of cavitation?

Back 6

Mechanical index MI - likelihood of cavitation

Front 7

Explain why we are concerned about Bioeffects in regards to cavitation and tissue Heating?

Back 7

Ultrasound is a form of energy.

Small potential to produce a bioeffect.

Ultrasound is absorbed by tissue and produces Heat (TI) .

Ultrasound energy interacts with microscopic, stabilized, gas bubbles in tissue (MI) mechanical index.

Front 8

What happens during Transit cavitations?

Back 8

Microbubbles burst

Front 9

Identify man-made ferroelectric materials

Back 9

PZT (lead, zirconate, titanate)

Front 10

Identify naturally occurring ferroelectric materials

Back 10

Quartz.

Tourmaline.

Front 11

Define piezoelectric

Back 11

Materials that convert electricity into sound and vice-versa are called piezoelectric or ferroelectric

Front 12

Identify types of exams performed with higher frequencies

Back 12

Superficial scanning = thyroid, breast, testicle, soft tissue, artery / veins of the extremities.

Superior image, less penetration

Front 13

Identify types of exams performed with lower frequencies

Back 13

Used for abdomen and OBGYN. More penetration to visualize deeper structures.

Image resolution is not as good but penetration is better.

Front 14

Describe the fresnel zone

Back 14

Near Zone.

Soundbeam converges

Front 15

Describe the fraunhofer Zone

Back 15

Far Zone.

Soundbeam diverges

Front 16

Describe the fraunhofer Zone

Back 16

Far Zone.

Soundbeam diverges

Front 17

What part of the ultrasound beam has the worst resolution

Back 17

Fraunhofer Zone sound beam diverges.

Deep in the far zone is where resolution is the worst.

Front 18

Describe the transducer you would choose to perform a carotid Doppler exam

Back 18

Linear array

Front 19

Which type of Doppler does not alias?

Back 19

Continuous wave

Front 20

Which type of transducer it requires at least two pzt crystals and does not create an image

Back 20

Continuous wave

Front 21

What do we use to clean the transducers

Back 21

T spray disinfectant

Front 22

Describe axial resolution

Back 22

Ability to distinguish two structures parallel to the sound beam.

Front 23

Describe axial resolution

Back 23

Ability to distinguish two structures parallel to the sound beam.

Front 24

Describe contrast resolution and what we manipulate to change it

Back 24

Ability to distinguish between different tissue Echogenicities.

Dynamic range knob.

Front 25

What is contrast resolution directly related to

Back 25

Dynamic range.

(high contrast vs. Low contrast)

Front 26

Describe lateral resolution

Back 26

Ability to distinguish two structures in a path of perpendicular to the sound beam.

(Side by side)

Front 27

Describe elevational resolution

Back 27

AKA slice thickness.

Thickness of the scanned tissue perpendicular to the scanned plane. Image plane is not paper-thin. Related to beam with.

Can caused fill-in of cystic structures.

Front to back.