1.2 Introduction to Ultrasound

Question 1

Describe the mechanism of image production from ultrasound.

Answer 1

A high-frequency sound wave is bounced off an object and an image produced from this.

Depending on the tissue, this will affect how much of the sound wave is transmitted and how much of it is reflected back.

This signal returns to the probe, which then sends the information to a computer, which uses an algorithm to create an image.

Either static (captured) or cine images (real time images - video) can be produced.

Question 2

How do you choose what frequency to use on the ultrasound probe?

Answer 2

Higher frequency - more superficial structures.

Lower frequency - more deep structures.

Question 3

What are the 2 main imaging planes used for ultrasound?

Answer 3

Sagittal and transverse.

The transverse plane is directly perpendicular to the sagittal plane.

Question 4

Orient yourself to the sagittal plane of an ultrasound.

Answer 4

Question 5

Orient yourself to the transverse plane of an ultrasound.

Answer 5

Question 6

Explain the appearance and meaning of the different rankings of …-echoic for USS.

Answer 6

Hyperechoic - reflects many echoes. (L image, showing thyroid lobe calcifications.)

Hypoechoic - reflects some echoes. (Middle image - breast lesion.)

Anechoice - reflects no echoes. (R image - black, represents a fluid-filled cyst.)