DX IMAGING

Question 1

In X-ray imaging, hard substances like bone and metal appear _________, while air, water and fat appear ______ on the film.

Answer 1

White;

Darker (Air is black…Fat is dark grey)

Question 2

Describe the rationale for varying shades of grey depending on the substance filmed from X-ray imaging.

Answer 2

The thicker the material, the more X-rays are being absorbed by it, therefore the less X-rays that are detected behind it, leading to a whiter color on the film.

Question 3

Name the four main types of imaging projections.

Answer 3

Anterior Projection (PA) - front side faces film, back is to x-ray
Posterior Projection (AP) - back side faces film, front faces x-ray
Left lateral - patient’s left side is close to film
Right lateral - right side is closest to film

Question 4

Describe the Penumbra Effect.

Answer 4

Involves refraction of light around objects. The closer an object is to the film the smaller, yet sharper the image. High resolution + Low magnification for closer objects.

Question 5

Name the two good projections that will get a relatively sharp image of the heart.

Answer 5

Anterior (PA) and Left lateral projections

Question 6

After a diagnostic image is made, ALL films are shown in what orientation?

Answer 6

All films are always looking at the viewer.

Question 7

Describe the Computerized Tomography scan

Answer 7

CT scan shows an axial image of a patient in supine position. Viewer looks up from the feet of the patient. The left side of CT = the right side of the patient.

Question 8

Describe the Magnetic Resonance Imaging.

Answer 8

MRI shows fat as white and bone as dark grey

Question 9

Describe Ultrasonography.

Answer 9

Ultrasound is a non-radiative method that’s great for visualizing solid-liquid surfaces through echoes. Fetuses, thromboses and gallstones are a few things that can be visualized.