Biophysics

Question 1

Complications of ultrasound

Answer 1

Heating
Cavitation
Microsteaming

Question 2

Soft markers for chromosomal abnormalities on USS

Answer 2

choroid plexus cyst - may be with T18
Echogenic bowel - may indicate obstruction or CF
Ongoing exomphalos - past 10 weeks
mild renal pelvic dilatation - soft

Question 3

Electrosurgery uses what frequency?

Answer 3

high frequency

Question 4

What is direct coupling?

Answer 4

tissue damage caused by the electrode touching another conducting instrument nearby.

Question 5

What phase is an HSG performed in

Answer 5

follicular phase - to prevent radiation to an early embryo

Question 6

modes in ultrasound

Answer 6

A mode - rarely used. Amplitude, too basic
B mode - normal. Brightness mode.
M mode - movement mode.
Doppler - looks at movement with colour

Question 7

Indices in fetal biophysical profiling

Answer 7

AFI
tone 
breathing
movement
HR

Question 8

Acoustic impedence

Answer 8

how opposition to the passage of sound waves and shows density and elasticity

Question 9

refraction

Answer 9

change of direction of the wave as a result in a change of speed

Question 10

diffraction

Answer 10

bending of waves during its passage as a result of interaction with obstacles

Question 11

Doppler effect

Answer 11

reflected waves from a moving object undergoing a frequency shift