Radiation Safety in Children

www.pedrad.org

Contents

• Why worry about radiation exposure?• What are radiation issues unique to children?• Examples of radiation doses in imaging• What does “ALARA” mean?• What is the “Image Gently Campaign”?• Methods radiologists use to decrease pediatric radiation exposure• Methods health care professionals can use to optimize radiation use

in children• Personal protection from radiation exposure at work

• Ionizing radiation is widely used in medicine and provides information that can save lives.

• However, some studies have suggested that ionizing radiation can result in biologic damage to living tissue, including genes and germ cells.

• Up to 70% of medical ionizing radiation exposure is from CT scans. X-rays and radionuclide studies also use ionizing radiation.

• In 2009, for the first time radiation exposure to individuals exceeded natural background radiation.

Why worry about radiation exposure?

Increase of medical ionizing radiation exposure from 1980 to 2006.

Fahey et al. THE JOURNAL OF NUCLEAR MEDICINE • Vol. 52 • No. 8 • August 2011

Question 1

Which of the following is true?

a) Ionizing radiation is widely used in medicine

b) Ionizing radiation may be harmful.

c) Ionizing radiation is of no concern.

d) A and C are correct.

e) A and B are correct.

What are radiation issues unique to children?

• Tissues are more radiosensitive at younger ages.• Longer lifetime for children to experience radiation-induced injury

(cancer, cataracts).

Hall Pediatric Radiology, Apr 2002, pg 226

Question 2

Children are at higher risk from ionizing radiation, because:

1. Children have a longer life span to experience injury

2. Tissue is more radiosensitive at a younger age

3. Exam doses can be cumulative over a life time

4. 1-3 are all true

Typical Radiation Dose Equivalents (mSv)

• Natural background (without medical exposure) 3.50

• Average annual technologist dose 3.20

• Airline passenger (per flight) 0.04

• Flight crew / attendants (per year) 1.60

• Dental x-rays 0.09

• Chest radiograph 0.01

• Mammogram 0.50 (to 7.0)

• Barium enema (adult) 8.75

• Computed tomography (Computed tomography (CT) ≤ 3 - 5.00

Relationship of Typical Ionizing Radiation Doses*

* 5 year old patient, effective whole body dose equivalent

Imaging studyChest x-ray equivalents

2-view chest 1

Fluoroscopy cystogram 16

Chest CT Up to 150

Abdomen CT Up to 250

Question 3

The radiation dose for one CT scan is equal to how many 2 view chest radiographs?

A. 1 CT = 1 CXR

B. 1 CT = 10 CXR

C. 1 CT = 150 CXR

D. 1 CT = 500 CXR

The ALARA Concept

ALARA is an acronym that stands for “As Low As Reasonably Achievable”.

ALARA is a concept that guides health care professionals towards reduction of exposure to ionizing radiation.

The concept is to expose a patient to the lowest possible radiation dose while maintaining diagnostic quality if the study is indicated.

Question 4

The following statement regarding the ALARA concept is correct:

a) ALARA stands for “As Low As Reasonably Achievable”.

b) ALARA reminds health care professionals of limiting radiation exposure whenever possible.

c) ALARA says that studies with radiation should not be used in children.

d) A and B are correct

Image Gently Campaign

The “Image Gently Campaign” was launched to raise awareness of ionizing radiation exposure risks.

The campaign reaches out to the general public, politicians, health care workers, patients and their families.

Question 5

The primary goal of the “Image Gently Campaign” is to:

a) Promote techniques that can lower radiation exposure when imaging children.

b) Raise awareness of radiation exposure risks in everyone.

c) Punish health care professionals who expose their patients to unnecessary levels of ionizing radiation.

d) A and B

Minimizing ionizing radiation exposure

Radiology professionals optimize ionizing radiation dose by:

• Imaging only when there is a clear medical benefit.• Optimizing imaging protocols for ages and sizes.• Providing updated equipment that utilizes less ionizing radiation.• Limiting radiation exposure to the area of interest.• Avoiding multiple scans.• Using non-radiation diagnostic studies, such as US and MRI,

when possible.• Involving a physicist to oversee quality assurance of dose

parameters and equipment.

Example:Dose reduction up to 50%can be achieved with “Automated Exposure Control” - a technology that is standard on modern CT scanners.

Radiology: Volume 258: Number 3—March 2011

Methods health care professionals can use to minimize ionizing radiation use in children

Health care professionals can significantly reduce ionizing radiation exposure by asking the following questions:

• Is it appropriate to do the exam?• Is this appropriate timing of the exam or should another

diagnostic test be done first?• What is the appropriate imaging modality for the clinical

question?

In order to answer some of these questions clinicians need to have a basic understanding of imaging modalities or access to radiologists for consultation.

Question 6

Clinicians can help reduce ionizing radiation exposure by asking the following questions:

a) Is it appropriate to do the exam?

b) Is this appropriate timing of the exam?

c) What is the appropriate imaging exam for the clinical question?

d) All the above.

Appropriateness

For many diseases there are clinical guidelines (“best practice”, “evidence-based medicine”) that set forth very well defined clinical criteria as an indication for imaging.

Clinicians should use these guidelines to determine if an imaging study, especially one with ionizing radiation exposure, is necessary.

Question 7

Which of the following ensures that the appropriate diagnostic imaging study is being ordered

a) Use guidelines from accepted “best practices” or “evidence-based medicine”

b) Use guidelines that have been established by the American College of Radiology

c) Consult with a radiologist.

d) All the above.

Timing and Modality

At times a clinical question can be answered using a modality that does not involve ionizing radiation exposure.

Clinicians should consider other modalities such as US or MRI when a clinical question requires imaging.

Reviewing results from previous exams may help in preventing unnecessary repetition of imaging studies.

Clinicians can consult with a radiologist to determine the best modality for a given clinical problem.

Personal protection

• Well fitted lead apron • Leaded glasses• Thyroid shield• Lead gloves • Barrier shields

Question 8

What are ways in which you can protect yourself from radiation exposure?

a) Keep exposure time short.

b) Keep a large distance from the radiation source.

c) Wear a lead apron and neck shield.

d) Drink lots of water.

e) A-C are correct

Pregnancy

Pregnant patients may not be able to undergo an imaging study in order to protect the unborn fetus from untoward effects.

As a referring health care provider you can help protect the patient and fetus by obtaining a history regarding possibility of pregnancy and ordering a pregnancy test whenever the possibility exists.

Pregnancy evaluation at Children’s National should be done for all female patients ≥10 years prior to ionizing radiation exposure. Patients' pregnancy status and date of LMP must be documented for all female patients 10 years or older.

Please discuss imaging options for your patient with a radiologist if you have any questions.

Question 9

Which of the statements below regarding imaging of pregnant patients are true?

a) Very high doses of radiation can harm a fetus.b) The potential for pregnancy should be considered in any female

in which an ionizing radiation imaging study is being consideredc) Only A is correct.d) A and B are correct

Downloadable Parent Pamphlets onwww.imagegently.org

• 2 page and 8 page material

Question 10

What should be my attitude towards ionizing radiation as a health care professional?

a) I should think of ionizing radiation as of medication- it can have side effects, especially in young children.

b) The use of ionizing radiation is not hazardous at all.

c) Like with any other medication, I need to weigh the risks against the benefits.

d) A and C are correct

Image Gently

Just like medications that you are prescribing, studies that involve radiation exposure may have long term effects particularly in

children.

Balance the risk and benefits for each individual patient in whom you are prescribing an imaging study.

Question 12

What should be my attitude towards ionizing radiation as a health care professional?

a) I should think of ionizing radiation as of medication- it can have side effects, especially in young children.

b) The use of ionizing radiation is not hazardous at all.

c) Like with any other medication, I need to weigh the risks against the benefits.

d) A and C are correct