About Radiation Dosage

Your doctor will order a radiology exam for you when it is needed for accurate diagnosis of your condition. There is no conclusive evidence of radiation causing harm at the level that is used for diagnostic exams. The benefits of diagnostic medical exams are vital to good patient care.

Radiation dose can be estimated for common exams. For comparison, in the United States each person receives about 3.0mSv (300mrem) of radiation exposure from background sources each year.

The following tables give dose estimates for some typical exams.

X-Ray Examinations

Effective Dose mSv (mrem)
0.1 (10)
Cervical Spine
0.2 (20)
Thoracic Spine
1.0 (100)
Lumbar Spine
1.5 (150)
0.7 (70)
Abdomen or Hip
0.6 (60)
Hand or Foot
0.005 (0.5)

Examinations and Procedures

6.0 (600)
CT Head
2.0 (200)
CT Chest
7.0 (700)
CT Abdomen/Pelvis
10 (1000)
Calcium Scoring
2.0 (200)

Nuclear Medicine

6.3 (630)
2.0 (200)
Heart (stress-rest)
10 (1000)

MRI and ultrasound procedures do not use ionizing radiation. If you have had an ultrasound or MRI examination, you are not exposed to radiation.

Sources: radiologyinfo.org, hps.org