Ultrasound Physics Introduction

What is the assumption made by the ultrasound machine about the speed of sound in tissues?

It is affected by the frequency of the sound wave
It decreases with depth
It is constant (correct)
It varies depending on the type of tissue

What type of artifact is characterized by a complete absorption or reflection of sound waves?

Dirty acoustic shadow
Edge shadowing
Acoustic enhancement
Clean acoustic shadow (correct)

What is the result of the machine processing compensating for the reduced attenuation of sound waves through a fluid-filled structure?

An area with no echoes
A hyperchoic area (correct)
A hypoechoic area
An anechoic area

What type of artifact is commonly seen at the tissue-gas interface?

Dirty acoustic shadow (C) Signup and view all the answers

What is the assumption made by the ultrasound machine about the direction of sound waves?

They travel in a straight line (A) Signup and view all the answers

What is the result of the sound wave being reflected or absorbed by an object, resulting in a shadow?

Acoustic shadowing (D) Signup and view all the answers

What is the cause of a false sludge image in the gall bladder?

The sound beam hitting the gall bladder wall and bile simultaneously (C) Signup and view all the answers

What is the primary function of the Piezo electrical crystals in a transducer?

To convert electrical current into sound waves (A) Signup and view all the answers

Which type of transducer is used for echocardiology and produces a pie-shaped image?

Sector transducer (B) Signup and view all the answers

What is the recommended frequency for imaging small dogs and cats?

7.5-10 MHz (A) Signup and view all the answers

What is the result of the sound beam hitting the liver and then being reflected back to the diaphragm-lung interface before going to the transducer?

Mirror Image artefact (A) Signup and view all the answers

What is the general rule for selecting the frequency of a transducer during an exam?

Choose the highest frequency that will penetrate the area of the patient (C) Signup and view all the answers

What is the term used to describe the number of times a cycle or wave is repeated per second in ultrasound physics?

Frequency (C) Signup and view all the answers

What happens to sound waves as they travel through a medium in ultrasound physics?

They lose strength (B) Signup and view all the answers

What is the term used to describe the distance traveled by sound waves in ultrasound physics?

Wavelength (C) Signup and view all the answers

What is the term used to describe the ability to detect two structures separately located in a parallel beam in ultrasound physics?

Resolution (D) Signup and view all the answers

What happens to sound energy in the process of absorption in ultrasound physics?

It is converted to heat (D) Signup and view all the answers

What is the result of sound waves encountering tissues of different acoustic impedance in ultrasound physics?

Reflection (A) Signup and view all the answers

What is the purpose of the Time Gain Compensation control?

To selectively amplify weakened echoes from deeper structures (B) Signup and view all the answers

What does the 'Focus' control on the ultrasound machine adjust?

The area of sharpest sound (B) Signup and view all the answers

What is the purpose of the acoustic gel in ultrasound imaging?

To provide a medium for sound waves to travel (D) Signup and view all the answers

What is the purpose of the 'Power' control on the ultrasound machine?

To increase the brightness of the image (B) Signup and view all the answers

What does the 'M-mode' of echo display record images in respect to?

Time (A) Signup and view all the answers

What is the purpose of the 'Doppler mode' of echo display?

To measure blood flow velocity within a blood vessel (A) Signup and view all the answers

What is the direction of the transducer in a sagittal plane?

Pointed cranially (D) Signup and view all the answers

What is evaluated in the transverse plane?

The size, shape, number, location, and margination of the structure (B) Signup and view all the answers

What is the echogenicity of a pure fluid without cellular content?

Anechoic (B) Signup and view all the answers

What is the direction of the transducer in a transverse plane?

Pointed towards the patient's right (A) Signup and view all the answers

What is evaluated in addition to the size, shape, number, location, and margination of a structure?

The homogeneity, texture, compressibility, surrounding tissue, and vascularity of the structure (C) Signup and view all the answers

What is the recommended scanning technique?

Pick a starting point and go in a clockwise fashion (B) Signup and view all the answers