WHICH ONE DOESN’T FIT?

THAT’S MORE LIKE IT.

RADIATION DOSAGE

CXR= 1/100 Background Radiation

Background Radiation/yr Sea level = 3 milli Sieverts

100 milli Rem = 1 milli Sievert

LARGEST STUDY GROUP OF

RADIATION HEALTH EFFECTS IS THE HIROSHIMA BOMB SURVIVORS

• There is an excess cancer risk seen in large groups of Hiroshima survivors.

• Doses from 50 to 100 milli Sieverts can produce cancer in humans.

TYPICAL EFFECTIVE DOSE VALUES

Imaging Examination (mSv)

LINEAR – NO THRESHOLD RISK CURVE

CT DOSE IS IN RANGE OF HIROSHIMA BOMB SURVIVORS DOSE

There is an excess cancer risk seen in large groups of Hiroshima survivors.

Statistically CT scans WOULD increase risk of cancer.

PERSPECTIVE

300/1000 die normally from cancer by age 80.

301/1000 of CT patients would die from cancer.

So out of our 1 million people 300,000 would get cancer by normal risk.. and the 1 million receiving a CT would produce a cancer group of 301,000.

TAKE HOME MESSAGE

Benefit of diagnostic information from CT Scan is far greater that radiation risk, if there is an appropriate indication

ALARA : Pediatric Radiology: Image Gently

Be especially careful in children, pregnant patients, thoracic imaging in young women, Repetitive scans

Whole body CT screening is inappropriate

Lung cancer screening –value ? Data being released