diagnostic imaging

Question 1

describe radiography

Answer 1

As X-rays pass through the tissues, they interact with
the photographic film behind the body
 Air attenuates X-rays a little
 Fat attenuates X-rays more than air but less than
water
 Bone attenuates X-rays the most

Question 2

Exposing parts of the body to high frequency sound
waves
 The waves are reflected back, and interpreted by a
computer
 The computer displays a real-time pictur

Answer 2

ultrasound

Question 3

Sometimes it is difficult to appreciate the
contrast agent in the vessels through the
overlying bony structures
 Images are obtained before the injection of
media.
 Contrast is injected and new images are
obtained of the vessels
 First set of images are subtracted from the
second, producing a solitary image of
contrast only

Answer 3

subtraction angiography

Question 4

Most inexpensive imaging technique
 Portable
 Causes very little harm to the patient (no radiation)
 Two potential physiologic effects
 1. Increases the inflammatory response
 2. Can heat soft tissue

Answer 4

ultrasound

Question 5

A patient lies flat on a bed
 An X-ray tube passes around the body, and a series
of images are obtained
 A computer carries out a complex mathematical
transformation on the multitude of images to
produce the final image
 A three dimensional image is created using many
two-dimensional images

Answer 5

computed tomographhy (CT)

Question 6

utilizes magnets, radio pulse waves, and
computers
 All dependent upon the free protons in the hydrogen
nuclei in molecules of water

Answer 6

MRI

Question 7

Because CT uses ionizing radiation, it works best
when examining tissues of

Answer 7

higher density (bone and bowels)

Question 8

between mri and ct which allows greater contrast between surrounding
tissues
 Allow for better visualization of tumors and other abnormalities

Answer 8

MRI

Question 9

does mri or ct use non ionizing radio waves

Answer 9

MRI it is less harmful esp with patients who will need a succession of similar test

Question 10

between ct and mri which is less inexpensive and more widely available

Answer 10

ct

Question 11

why is nuclear medicine imaging different than other tests

Answer 11

Different than other tests because it shows
physiologic function rather than traditional anatomy
like CT/MRI

Question 12

what is this describing

A radiotracer is entered into the body and into the
organ or area of interest
 There it gives off energy in the form of gamma
radiation
 The energy is detected and analyzed and an image is
created

Answer 12

nuclear medicine imaging

Question 13

what is a positron

Answer 13

anti electron Imaging modality for detecting positron-emitting
radionuclides
 A positron is an anti-electron, which is a positively
charged particle of antimatter
 Positrons are emitted from the decay of proton-rich
radionuclides