Table 1.
Radiation doses from gastrointestinal imaging studies in comparison to background radiation, condensed from RadiologyInfo.org[9] and Mettler et al[10]
| Imaging procedure | Average effective dose (mSv) | Time period for equivalent effective dose from natural background radiation1 |
| Multiphase CT abdomen and pelvis | 31 | 10.3 yr |
| PET/CT | 25 | 8.3 yr |
| CT Abdomen and Pelvis | 10 | 3.3 yr |
| CT Colonography | 10 | 3.3 yr |
| CT Abdomen | 8 | 2.7 yr |
| Barium Enema | 8 | 2.7 yr |
| Small bowel follow-through | 5 | 1.7 yr |
| X-ray abdomen | 0.7 | 2.8 mo |
1
Based on the assumption of an average effective dose of 3 mSv per year from natural background radiation. CT: Computed tomography; PET: Positron emission tomography.