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 /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