Table 4.
Effective dose and organ radiation doses for abdominal/pelvic CT examinations estimated at our institution
| Routine Abdomen-Pelvis | Suspected Aneurysm or Dissection | Routine Upper Abdomen | |
|---|---|---|---|
| Effective dose (mSv)a | 14.8 | 17.2 | 6.2 |
| Organs or tissues | Organ Dose (mGy or mSv)b | ||
| gonads | 31.3 | 35.9 | 0.8 |
| bone marrow (red) | 12.4 | 14.3 | 3.8 |
| colon | 23.2 | 26.9 | 0.7 |
| lung | 7.4 | 8.7 | 7.5 |
| stomach | 24.8 | 29.4 | 21.6 |
| bladder | 32.4 | 38.9 | 0.2 |
| breast | 1.4 | 1.6 | 1.3 |
| liver | 22.7 | 27.3 | 20.5 |
| esophagus (thymus) | 1.1 | 1.3 | 1.1 |
| thyroid | 0.1 | 0.1 | 0.1 |
| skin | 8.8 | 10.2 | 3.3 |
| bone surface | 16.4 | 19.1 | 6.9 |
| remainder | 12.1 | 14.0 | 3.8 |
aEffective doses and organ doses are reported for a single scan.
bThe radiation dose, a measure of ionizing energy absorbed per unit of mass, is expressed in grays (Gy) or milligrays (mGy); 1 Gy = 1 joule per kilogram. The radiation dose is often expressed as an equivalent dose in Sieverts (Sv) or millisieverts (mSv). For x-ray radiation, which is the type used in CT scanners, 1 mSv = 1 mGy.