Radiation Risk of X-ray Examinations

9 Questions

Ionisation within the tissues

Indirect interaction

Acute radiation syndrome

5 years

All of the above

A sequence of images over time

To produce images in rapid sequence

Bone fracture diagnosis

Real-time X-ray movies

Study Notes

Radiation risk refers to the damage caused by ionising radiation through energy deposition in tissues, leading to ionisation within tissues.
There are two types of radiation interactions with tissue: direct and indirect.
Direct interaction: radiation energy is directly transferred to DNA, causing structural changes in its molecules.
Indirect interaction: radiation energy is absorbed by water molecules, forming free radicals that damage DNA molecules.

There are two types of adverse health effects: deterministic and stochastic effects.
Deterministic effects: high radiation doses, resulting in immediate damage (within minutes, hours, days, or weeks).
Stochastic effects: low radiation doses, potentially leading to cancer development, with a lag period of at least 5 years, and up to 10 or 20 years.

Fluoroscopy: continuous acquisition of a sequence of X-ray images over time (real-time X-ray movie of the patient).
Fluoroscopic systems use X-ray detector systems capable of producing images in rapid sequence.
Applications of fluoroscopy: positioning catheters in arteries, visualising contrast agents, invasive therapeutic procedures (surgery), and making X-ray movies of anatomic motion (e.g., heart or oesophagus).