Diagnostic imaging

Conventional radiography

image

Radiography is the use of x-rays to visualize the internal structures of a patient. X-Rays are a form of electromagnetic radiation, produced by an x-ray tube. The x-rays are passed through the body and captured behind the patient by a detector; film sensitive to x-rays or a digital detector. There is variance in absorption of the x-rays by different tissues within the body, dense bone absorbs more radiation, while soft tissue allows more to pass through. This variance produces contrast within the image to give a 2D representation of all the structures within the patient.

Common clinical applications

  • Chest: to assess lung pathology
  • Skeletal: to examine bone structure and diagnose fractures, dislocation or other bone pathology
  • Abdomen: can assess abdominal obstruction, free air or free fluid within the abdominal cavity
  • Dental: to assess common dental pathologies such as cavities or abscesses

Safety

  • Radiography utilizes x-rays, a proportion of which are absorbed within the body. The potential effects on the body from ionizing radiation are categorized as deterministic (including skin reddening or burns) dependent on the dose or stochastic (long term effects such as cancer).
  • Due to the potential risk from ionizing radiation, exposures from radiography procedures must adhere to the ALARA principal; "as low as reasonable achievable" to obtain a diagnostic examination.
  • Special consideration should be given to pregnant women and children as they are more sensitive to radiation.
  • X-ray personnel should at all times ensure that the benefit of the examination will outweigh potential risk from radiation exposure, and that the patient is exposed to as little radiation as possible.