How can we minimize increased radiation dose to patients and personnel during medical procedures?

Minimizing Radiation Dose to Patients and Personnel During Medical Procedures

To minimize increased radiation dose to patients and personnel during medical procedures, healthcare facilities should implement a comprehensive approach focusing on proper equipment selection, calibration, protocol optimization, and personnel training while fostering a culture of radiation safety.

Physician Responsibilities

Procedure Selection

• Consider radiation exposure as an important factor when selecting diagnostic or therapeutic procedures, weighing the risk-benefit relationship 1
• For younger patients without comorbidities, consider alternative imaging procedures that do not use ionizing radiation (e.g., cardiac magnetic resonance or echocardiography) 1
• Use appropriate clinical criteria as a starting point for making procedure selection decisions 1

Procedure Conduct

• Understand the determinants of patient dose and adjust procedure conduct to achieve successful diagnosis or therapy while employing minimal necessary dose 1
• For x-ray fluoroscopy:
  • Minimize beam-on time, use appropriate beam collimation, and optimize system positioning 1
  • Select imaging protocols (detector dose, frame rate) that minimize dose while providing diagnostic quality images 1
• For CT imaging:
  • Select the lowest dose imaging protocol that yields diagnostic quality images 1
  • Limit examination to the body region of interest 1
• For radionuclide scintigraphy:
  • Select radionuclide species that delivers least radiation exposure while answering clinical questions 1
  • Administer the smallest radiopharmaceutical activities likely to ensure diagnostic image quality 1
  • Use stress-first imaging for patients with reasonable pretest probability of normal study 1

Facility Management

Equipment Considerations

• Ensure radiological equipment can generate diagnostic-quality images at minimal dose 1
• Replace or renovate obsolete equipment that requires greater than current state-of-the-art dose 1
• Collaborate with equipment company engineers and radiological physicists to verify optimal calibration 1
• Provide user control of imaging dose parameters to allow operators to select protocols balancing image quality and dose 1

Quality Assurance and Monitoring

• Monitor facility's overall radiological performance by tabulating patient procedure doses and personnel doses 1
• Investigate and explain individual large outlier exposures, taking corrective action when indicated 1
• Implement proper quality assurance to verify equipment performance and calibration 1
• Monitor metrics of patient and personnel exposure 1

Personnel Protection Strategies

Protective Practices

• Implement the pdO-DST approach (patient dose Optimization, Distance, Shielding, and Time) 2
• Recognize that reducing patient radiation dose also decreases occupational exposure 2
• Use appropriate shielding devices (e.g., lead glasses and ceiling-suspended shields) for interventional procedures 2
• Combine multiple radiation shields as no single shield is perfect 2

Specific Techniques

• Minimize use of digital subtraction acquisitions during fluoroscopy 3
• Avoid lateral angulation of the C-arm when possible 3
• Use higher magnification levels when appropriate, as decreasing field size can reduce kerma area product 3
• Be diligent about using shielding during all fluoroscopic procedures 3

Education and Training

• Provide proper training to ensure all clinical personnel understand radiation safety principles 1
• Educate radiological medical workers about methods to estimate and reduce both patient dose and occupational exposure 2
• Promote routine use of radiation protection methods, as they must be used properly to be effective 4
• Ensure personnel wear dosimeters for every case to monitor occupational dose 4

Common Pitfalls and Caveats

• Digital subtraction acquisitions account for a large fraction of radiation dose to all individuals 3
• Lateral projections significantly increase dose rates compared to posterior-anterior projections 3
• Ineffective shielding, particularly around anesthesia equipment, can lead to higher than necessary exposure 3
• While patient dose tracking systems exist, they add little practical clinical value for individual patients 1
• If proper protection practices are followed, annual effective dose for interventionalists should be well below 10mSv/y 4