Dr Thomas Gan

Sport & Exercise Medicine

Radiation From Scans: What you need to know


  • Benefits from a scan may outweigh any potential risk of harm from the risk of radiation used
  • MRI and ultrasound procedures do not use ionizing radiation
  • There is no conclusive evidence of radiation causing harm at the levels patients receive from scans
  • Although high doses of radiation are linked to an increased risk of cancer, the effects of the low doses of radiation used in diagnostic imaging are not known
  • Radiation doses differ for each person because of differences in machines and their settings, the amount of radioactive material given in a nuclear medicine procedure, and the patient’s metabolism.
Type of Scan



Living in Australia for 1 year

XRAY
Chest
Extremity (hand / foot)
Joint (knee, ankle etc)
Cervical spine
Thoracic spine
Pelvis & Hip
Lumbar spine

CT
Cervical Spine
Pelvis
Thoracic Spine
Lumbar Spine

Nuclear Medicine
Bone Scan
SPECT-CT

For Comparison
Mammogram
High resolution Chest CT
Head CT
Radiation Dose (mSv)


3.000



0.020
0.005
0.060
0.270
1.400
1.500
1.800


4.800
6.200
8.000
8.000


4.200
Combination


0.130
1.500
2.200
No. of Chest XR’s


150



1
0.25
3
13.5
70
75
90


240
310
400
400


210
of CT


6.5
75
110
Equivalent amount of extra radiation living in Australia

1 year



3 days
1 day
7 days
1 month
6 months
6 months
7 months


18 months
2 years
3 years
3 years


18 months
+ Bone Scan


2 weeks
6 months
9 months
NB: Figures listed above are approximates only. Data sourced from RADAR Medical Procedure Radiation Dose Calculator, Radiation Exposure From Medical Diagnostic Imaging Procedures, Health Physics Society