What you should tell your patients about radiation

What you should tell your What you should tell your patients about radiation patients about radiation

Lisa Lowe MD, FAAPLisa Lowe MD, FAAPProfessor, Univ of MO-Kansas CityProfessor, Univ of MO-Kansas City

Pediatric Radiologist, Children’s Mercy Pediatric Radiologist, Children’s Mercy Hospitals & ClinicsHospitals & Clinics

Learning Objectives

After this talk, learner should be able to:• Explain general radiation risk to

patients and parents• State ways to lower radiation exposure

in children• Be able to list helpful resources to

determine the best radiology test

Outline

• History and Background

• Radiation Risk• Increased use of CT• Image Gently• Helpful resources • What can you say?• What can we do?

History: Roentgen discovers the X-ray!

• Dec 1895 – Publication• 1 week later -

radiograph of wife’s hand

History: Radiology - fastest translational research

• Mid 1896, in practice, including fluoroscopy

• < 9 months from publication

History: X rays became a public spectacle

• Patented shoe fitting fluoroscope– Bloomingdales

• FASCINATION!

History: Side effects appeared later

• Vision impaired• Skin injury• Hair loss

History: Risk of radiation “exposed”

• 1956 Alice Stewart, MD, reports X-Ray risks to fetuses– Argued no radiation was safe– Radiation effects grossly underestimated

• 1945 US drops atomic bomb– Life Span Study cohort of atomic bomb survivors– > 50 years– Hiroshima Nagasaki– Increased risk of

solid cancers– Children highest

cancer mortality rates

Radiation risk: Biological effects of radiation

Damage to DNA• Damage to DNA is rapid • Damage to DNA may lead to genomic instability• Induction of cancer takes many years

• Children are more radiosensitive• Longer lifetime to manifest

radiation-induced injury (cancer, cataracts)

• Children 2-10x more sensitive than adults

Radiation Risks in Children:No Debate

Increased use X-rays: Invention of CT

• 1979 Nobel Prize in Physics

Allan Cormack Godfrey Hounsfield

Increased use: Helical CT

• Significant increase in the use of CT from 2001 to 2006– Increase of 10% per year

• 62 million CTs done per year– 6-11% of all CT’s done in children

• Initially multidetector and 3D CT increased radiation doses by 3 to 10X

• 50% of all medical radiation• ?? Dose quantification

Arch, Michael and Donald P. Frush. “Pediatric Body MDCT: A 5-year follow up survey of scanning parameters used by Pediatric Radiologists.” AJR 2008; 191: 611-617.

Increased use of CT:AJR Feb 2001

< 20% cases

1 in 500 - 1,000

Brenner et al: AJR 2001

Increased use & radiation risk

• Each exam (therefore dose) is cumulative

Hall. Pediatric Radiology. Apr 2002

Increased use & radiation risk

• AGE at exposure is most important risk factor• Females 2X males

– Breast– Thyroid

Image Gently Campaign

• Society for Pediatrics Radiology (SPR) & American Academy of Pediatrics (AAP) plus 33 other medical organizations formed the Alliance for Radiation Safety in Pediatric Imaging - 2008

• Represents over 400,000 healthcare professionals promoting appropriate and high quality CT for children

Image Gently Campaign

• ALARA principle– As Low As Reasonably

Achievable• 4 Image Gently guidelines:

– Scan only when necessary– Scan only indicated region– Reduce or “child-size” the

radiation dose– Scan once– www.imagegently.com

Helpful resources: ACR website

• Imaging guidelines and appropriateness criteria on the Amer College of Radiology (ACR) website:– http://www.acr.org/s_acr/bin.asp?TrackID=&S

ID=1&DID=14800&CID=1848&VID=2&DOC=File.PDF

Helpful resources: AAP website

• Radiology section of the AAP

• Imaging guidelines: http://www.aap.org/sections/radiology/default.cfmRadiation safety information for parents & pediatricians

Radiation report card

Helpful resources: CMH Radiology website

• Children’s Mercy Hospital Radiology website

Sample newsletters:

• Image gently campaign

How do we respond?

One size does NOT fit all We all must ask?• Appropriate to do

exam?• Appropriate timing of

exam?• Appropriate modality?

• Radiologists’ responsibility Understand radiation doses Review requests for higher dose

studies Discuss with clinicians and

parents/patients PRN Child size technical factors

How Do We Respond?

Examples

• Sinus CT– Old: 150 mAs– New: 30 mAs

• Scoliosis CT• Craniosynostosis CT

5x lower dose!}

• Pediatricians’ responsibility:Understand radiation doses of modalities

Know which facilities are “kid friendly!Don’t ass-u-me?ASK, even demand!

Order on medical indications not parental/legal pressure

Discuss options with radiologist PRN Consider information for parents PRN

How Do We Respond?

Talking to parents

1. Discuss risk vs. benefit2. Use websites for more detailed

explanations3. Compare to other every day risks

Typical radiation doses compared compared to background (3.5 mSv/yr)to background (3.5 mSv/yr)

Procedure Effective dose Comparable background dose*

Chest x-ray 0.02mSv 1 monthVCUG 0.3mSv 3 monthsDental X-rays 0.9 mSv 6 monthsLumbar spine 1.3 mSv 7 monthsCT head 2mSv 8 monthsUpper GI 3mSv 1 yearBarium enema 7mSv 2.3 yearsCT abdomen 10mSv 3 years1 Airline flight 0.3mSv 2-3 months

*Average background dose is 3.5 mSv/year

Risk of death from various activities

Activity Risk of death per million/year

Having a chest X-ray 1Visiting Denver for 2 months 1Traveling 5,000 by air 5Fishing (drowning) 10Traveling 1,500 miles by car 40Motorcycling for 1,000 200Smoking 1 pack/day 3,500Being > 55 years age 10,000

What is CMH doing to lower doses?

Pediatric radiologist is actively involved

• Using US and MRI when possible– Appendicitis and screening

• Pulsed fluoroscopy– UGI/VCUG – Up to 10X less dose

What is CMH doing to lower doses?

Pediatric radiologist is actively involved• Child size all CT doses

– New protocols: 5x less dose

• Av CT dose: 2009– CMH: 1025 mSv – Other providers: 1818 mSv

44% less 44% less radiation!!radiation!!

What is CMH doing to lower doses?

We make sure your patient gets the:• Right test (best test with least radiation)

– ? US or MRI• Right time

– ? Does something else need to be done first?• Right way (individualize protocols)

– ? Contrast or not– Lowest radiation dose possible

• 44% less for CT on average

Thanks for your attention

Questions?