Medical Imaging

Question 1

Define Radiology

Answer 1

A branch of medicine concerned with the use of radiant energy or radioactive material in the diagnosis and treatment of disease.

Question 2

MAMMOGRAPHY

Answer 2

This is a specific kind of x-ray imaging that uses a low dose x-ray system specifically designed for creating detailed images of the breast, can be used to detect early breast cancer in women with no symptoms or in woman with symptoms to diagnose the disease.

Question 3

FLUOROSCOPY:

Answer 3

medical imaging that shows a continuous x-ray image on a monitor like a movie

Question 4

ANGIOGRAPHY:

Answer 4

examination of arteries, veins and organs to diagnose blockages

Question 5

How is angiography performed?

Answer 5

inserting a thin tube called a catheter into the artery or vein from an access point (in the groin or arm) then a contrast agent is injected to make the blood vessel appear visible on the x-ray image.

Question 6

Tomography:

Answer 6

produces images of single tissue plane

Question 7

Advantages of CAT/CT

Answer 7

• Fast
• Readily available
• Good imaging of bony structures, abdomen and lungs

Question 8

Disadvantages of CAT/CT

Answer 8

• High dose of radiaton

- Not so good at imaging soft tissue such as the brain and spinal cord

Question 9

Scintigraphy

Answer 9

use of gamma radiation to form images following the injection of various radiopharmaceuticals
These are detected by a gamma camera that converts the absorbed energy into an electrical signal which is then analysed by a computer and displayed as an image.

Question 10

Advantages of Scintigraphy

Answer 10

• High sensitivity
• Functional information as well as
• Anatomical information

Question 11

Advantages of PET

Answer 11

• Good functional information

- Good localization of pathology

Question 12

Disadvantages of PET

Answer 12

• High radiation dose

- Not so good at differentiating between different pathologies

Question 13

MRI

Answer 13

magnetic field and radiofrequency pulses to produce detailed images of body’s internal structures as cross-sectional images or slices

Question 14

Advantages of MRI

Answer 14

Provides high quality images with excellent contrast detail of soft tissue and anatomic structures such as gray and white matter in the brain. DOES NOT EMMIT IONIZING RADIATION.

• Gold standard of imaging
• No radiation
• Good localization of pathology
• Good differenciation between pathologies
• Excellent soft tissue imaging (brain and spinal cord)

Question 15

What is the tapping sound in the MRI

Answer 15

gradient magnets being turned on and off

Question 16

MRI SEQUENCES: What does this mean and what are the three kinds

Answer 16

This is a number of radiofrequency pulses and gradients that result in a set of images with particular appearance:
High signal intensity = white
Intermediate signal intensity = grey
Low signal intensity = black

Question 17

hat are the two different forms of MRI images

Answer 17

T1 and T2 weighted images.
Due to timing of radiofrequency pulse sequences used:
T1 = FAT TISSUE
T2 = FAT AND WATER