Ultrasound

Question 1

what is ultrasound

Answer 1

high frequency sound waves
produced by passage of a current through a transducer containing piezoelectric crystals
vibration / oscillation of piezoelectric elements which convert electrical current to mechanical energy which produces sound waves propagate through body
sound waves travel at known speed, reflected back as echos
determine depth and density of tissue
convert from mechanical energy to electrical energy for picture

Question 2

probes used

Answer 2

renal 3.5
trus 7
testicle penis 7-10

Question 3

doppler effect

Answer 3

Doppler - ambulance effect
Sound produced or reflected from a moving object
varies proportionally to the velocity of the movement
Transducer at an angle to the vessels
Tells us about speed and direction of blood flow

Question 4

transducer design linear vs curvilinear

Answer 4

linear array - transrectal, resolution at 90 degrees to the direction of sound travel and constant at any depth
high freq
used superficial
narrow image

curved - wider beam but reduced resolution at depth, used for abdomen
wider image

Question 5

ultrasonic lithotripsy

Answer 5

hollow probe
energy delivered to PE crystal
oscillations 23-27KHz
channeled down probe
low pressure ballistic impact
subsequent sunction

Question 6

ballistic litho

Answer 6

compressed air 
0.35-0.5 mPa
pressurizes projectile into stone
shockwave transmitted via stone
suctioned aware
magnetic core vibration 15-30Hz
risk stone propulsion and urothelial perforation

Question 7

ultrasound waves

Answer 7

no in EM spectrum
not radiation
are acoustic waves that propagate through a medium by vibrating the molecules make up the medium