History Of Ultrasound

Question 1

Frequency of Infrasound

Answer 1

Below 20 hertz

Below audible sound range

Question 2

Frequency of Audible sound

Answer 2

20-20 000 hertz

We can hear

Question 3

Frequency of Ultrasound

Answer 3

Above 20 000 hertz

Question 4

Frequency of Diagnostic Medical uses

Answer 4

1-30 Megahertz

1 Mega = 1 Million

Question 5

Frequency of Therapeutic uses

Answer 5

1-3 Megahertz

1 Mega = 1Million

Question 6

Which is more Intense:
Diagnostic Medical uses (1-30 Megahertz)
Therapeutic uses (1-3 Megahertz)

Answer 6

Therapeutic is more intense

Question 7

What year did an Italian priest/scientist find that a blinded bag could function, but a deaf one could not?

Answer 7

1793

Question 8

What and When did the Currie Brothers discover?

Answer 8

In 1880 they discovered the piezoelectric effect

Question 9

What is the piezoelectric effect

Answer 9

Apply pressure waves to quartz crystal caused electrical pulses (voltage)

Question 10

What is the reverse piezoelectric effect?

Answer 10

Apply voltage (electrical pulses) to a quartz crystal and it produces pressure waves.

Question 11

What are a couple ways in which ultrasound can be used besides medical uses?

Answer 11

The military

• 1906 used sonar to detect icebergs
• 1916 used to detect submarines

Metal flaw detectors
-1928 these were used to check integrity of metal for ships/aircrafts

Question 12

Who was Karl Dussik?

Answer 12

• A neurologist/psychiatrist who used ultrasound for medical purposes (1942) in Vienna
• A-mode scanning to see brain tumor

Question 13

Who was George Ludwig

Answer 13

Used A-mode scanning to diagnose gallstones.

Question 14

Who was Hertz and Edler

Answer 14

• 1954 they used A-mode to show heart motion

- lead to development of M-mode ultrasound

Question 15

Who was Ian Donald?

Answer 15

• “Father of Obstetrical ultrasound”
• used ultrasound to identify gestational sac
• developed biparietal diameter measurement (BPD)

Question 16

What and When did Ian Donald and Tom Brown develop?

Answer 16

In 1957 they developed the first compound scanner (gave an image)

Question 17

What is Real Time scanning (dynamic scanning) and when was it introduced?

Answer 17

• 1973
• when a single frame or image is created several times per second to give the appearance of movement (B-mode)
• probe is constantly firing/listening

Question 18

A-mode

Answer 18

-Amplitude
-most basic form
-amplitude over time graph
(Distance between transducer and structure determines where an echo is seen on time axis; spike is produced based on amplitude of echo)
-each spike is a reflector

Question 19

B-mode

Answer 19

• brightness (white is stronger : black is not there)
• display intensity (amplitude) of echo by varying brightness of dots
• each dot is separate echo intensity and location
• compounding dogs make a 2D image

Question 20

Bi-stable

Answer 20

• is a B-mode image
• ONLY black and white
• NO soft tissue differentiation
• use cathode ray tube for display

Question 21

Gray Scale

Answer 21

• is B-mode
• has many shades of grey
• uses scan converter NOT cathode ray tube

Question 22

M-mode

Answer 22

• motion modulation

- series of B-mode dots displayed on motion over time graph, the structures motion can be seen

Question 23

Doppler

Answer 23

Means of displaying the motion of red blood cells by detecting a perceived change in the frequency of the emitted sound
(Goes out/comes in at different frequencies)

Question 24

When did “static scanning” come to term?

Answer 24

Only after real time scanning was introduced

Question 25

What means the same as static scan?

Answer 25

Static Scan B-scan Articulated arm scan

Question 26

What is contacts scanning?

Answer 26

Is when the transducer actually touches the patient. Describes transition from having patients placed in water bath

Question 27

What is Compound (static) mode?

Answer 27

Use B-mode to place numerous “lines” of dots together to form an image

Question 28

What does therapeutic ultrasound do to the body?

Answer 28

It heats up muscle tissue, increases blood flow, overall speeding up the healing process

Question 29

A compound scanner is the same as what?

Answer 29

Static scan | Articulated arm scan

Question 30

Simply describe A-mode

Answer 30

Amplitude mode | Strength of returning echos are shown as vertical spikes along time axis

Question 31

Simply describe B-mode (real time, compound)

Answer 31

Brightness mode | Strength of returning echos are shown as shades of grey (black is NO amplitude)

Question 32

Simply describe M-mode

Answer 32

Motion mode | Where movement of structures is represented over time

Question 33

Compare bi-stable and gray scale imaging

Answer 33

Bi-stable : displays back and white, lots of contrast, little tissue differentiation Gray scale : up to 256 shades and uses scan converter

Question 34

What is difference between static scanning and real time scanning

Answer 34

Static : articulated arm, only capable of one picture at a time Real-Time : free hand, appears as live motion