Question

1. what type of patient preparation is required to achieve a diagnostic ultrasound?

a. heavy sedation
b. enema and 24 - hour fasting
c. shaving the hair coat
d. application of a waterless shampoo

1. what would be an example of a negative contrast agent?

a. air
b. barium
c. transducer gel
d. meglumine

1. the distance from the target to the recording surface with radiographs is called what?

a. focal film distance
b. penumbra distance
c. radiographic source distance
d. source - image distance

1. which type of digital radiograph uses a scanner laser beam to produce an image?

a. mri
b. cr
c. ccd
d. dr

Explanation:

• Question 27: For a diagnostic ultrasound, shaving the hair coat (option c) is often done to ensure better contact of the ultrasound transducer with the skin. Heavy sedation (a) is not typically required. Enema and 24 - hour fasting (b) are more relevant for some other imaging or gastrointestinal procedures. Application of a waterless shampoo (d) is not a standard preparation for ultrasound.
• Question 28: Negative contrast agents are substances that appear dark on the imaging modality. Air (option a) is a common negative contrast agent. Barium (b) is a positive contrast agent. Transducer gel (c) is used for ultrasound to improve coupling, not as a contrast agent. Meglumine (d) is not a negative contrast agent.
• Question 29: The distance from the target (X - ray source) to the recording surface (film or digital detector) in radiographs is called the source - image distance (option d). Focal film distance (a) is an older term that is less accurate. Penumbra distance (b) refers to the unsharpness in an image. Radiographic source distance (c) is not the standard term.
• Question 30: Computed Radiography (CR, option b) uses a scanner laser beam to read the latent image on a photostimulable phosphor plate and produce a digital image. MRI (a) uses magnetic fields and radio waves. CCD (c) (Charge - Coupled Device) and DR (d) (Direct Radiography) do not use a scanner laser beam in the way described for CR.

Answer:

1. c. shaving the hair coat
2. a. air
3. d. source - image distance
4. b. CR