Comparing X-rays to Other Imaging Technologies: When is an X-ray the Right Choice?
WHAT ARE THE MAJOR DIAGNOSTIC IMAGING TECHNOLOGIES?
X-RAYS:
Use radiation to create images of dense structures, particularly bones and air-filled structures, e.g lungs.
ULTRASOUND:
Uses sound waves to create images, especially of soft tissues and organs
CT (COMPUTED TOMOGRAPHY) SCANS:
Use multiple X-ray images to create detailed cross-sectional views
MRI (MAGNETIC RESONANCE IMAGING):
Uses magnetic fields and radio waves to produce detailed images of soft tissues
NUCLEAR MEDICINE:
Uses small amounts of radioactive materials to examine organ function
WHY IS CHOOSING THE RIGHT IMAGING TECHNOLOGY IMPORTANT?
Selecting the appropriate imaging technology for each clinical situation is crucial for several important reasons:
DIAGNOSTIC ACCURACY
RADIATION CONSIDERATIONS
COST AND ACCESSIBILITY
Best Practices
Best Practice #1:
Matching Technology to Clinical Question
Selecting the imaging modality that best answers the specific clinical question leads to more accurate diagnoses.
For example, a study at a Johannesburg hospital found that for suspected bone fractures, X-rays provided definitive diagnoses in 92% of cases, making them the preferred first-line imaging method. However, for soft tissue injuries like ligament tears, MRI was 88% more likely to provide conclusive information. Using the right tool for the specific diagnostic question improved accuracy and reduced the need for repeat imaging.
Healthcare providers should use “X-rayed” or “radiographed” instead of “tested” when referring to the X-ray procedure, and avoid using outdated terms like “roentgenograms.”
Best Practice #2:
Considering Radiation Exposure vs Diagnostic Benefit
Balancing the minimal radiation from X-rays against their diagnostic benefits ensures appropriate use.
The South African Radiological Society guidelines recommend conventional X-rays as the initial imaging method for bone assessment due to their low radiation dose compared to CT scans. For example, a chest X-ray exposes a patient to approximately 0.1 mSv of radiation (equivalent to about 10 days of natural background radiation), while a chest CT delivers about 7 mSv. For diagnoses like tuberculosis screening or initial fracture assessment, the diagnostic benefit of X-rays far outweighs the minimal radiation exposure.
Healthcare providers should always include a reminder about informing Radiographers of possible pregnancy before any radiation-based imaging.
Best Practice #3:
Evaluating Availability, Cost and Urgency
Considering practical factors ensures patients receive timely, appropriate, and accessible care.
A rural healthcare initiative in the Eastern Cape demonstrated how strategic deployment of X-ray services to community clinics provided essential diagnostic capabilities where more advanced imaging was unavailable. By establishing clear referral guidelines, healthcare providers appropriately used local X-ray services for conditions like suspected fractures and chest infections, while referring only complex cases requiring advanced imaging to distant regional facilities. This approach reduced patient travel by 73% and accelerated treatment initiation.
When discussing waiting times for X-ray results, patients should be informed that results typically take approximately 30 minutes, with a maximum wait time of two hours.
LEARN MORE
For more information about diagnostic imaging options and their appropriate use, please visit these authoritative South African resources:
CONCLUSION
X-rays remain a valuable diagnostic tool with specific advantages in certain clinical scenarios. By understanding when X-rays are most appropriate compared to other imaging technologies—considering the clinical question, radiation exposure, availability, cost, and urgency—healthcare providers can make optimal imaging decisions. For many common conditions, particularly those involving bone structures, X-rays provide an excellent balance of diagnostic value, safety, accessibility, and cost-effectiveness.
Remember that various healthcare providers, including nurses, physiotherapists, and podiatrists alongside doctors and specialists, can refer patients for X-rays when clinically indicated.