Patient Dose Reduction and Optimization

Question 1

Are radiation doses of the image greater at the periphery or at the center along the x- and y- axis?

Answer 1

periphery

Question 2

What is the gradient saying radiation dose is greater at the periphery dependent on?

Answer 2

patient size

Question 3

How much radiation dose do smaller patients, including pediatrics, obtain?

Answer 3

little to nothing

Question 4

At what level of intensity are the entrance and exit radiation doses in smaller patients?

Answer 4

equal intensity

Question 5

What is a result of entrance and exit radiation being of equal intensity?

Answer 5

uniform distribution of radiation

Question 6

When is absorbed dose considered to be greater in smaller patient’s?

Answer 6

when all technical factors remain the same?

Question 7

What are 5 recommendations for reducing pediatric dose?

Answer 7

eliminate CT scans for inappropriate indications, reduce multiphase scanning, reduce mA, reduce kVp and increase pitch

Question 8

What are examples of multiphase exams?

Answer 8

pre-contrast and delays

Question 9

What campaign was begun by the Alliance of Radiation Safety in pediatric imaging to help reduce pediatric radiation exposure from CT imaging?

Answer 9

Image Gently

Question 10

What are three suggestions of the Image Gently campaign that helps reduce patient exposure?

Answer 10

“child sized” kVp and mAs
one single-phase exam
scan only the indicated area

Question 11

What other technique is used by the CT scanner to reduce patient dose by limiting the amount of noise caused by low dose radiation?

Answer 11

iterative reconstruction