Understanding and Minimizing X-Ray Radiation in the Operating Room
Medical X-ray from devices like a C-arm are invaluable for guiding complex surgeries. However, they emit ionizing radiation, which requires proper understanding and strict safety protocols to protect both patients and medical staff.
How X-Ray Radiation Affects the Body
When X-ray pass through the human body, three things can happen: some pass through, some are absorbed, and some scatter in various directions.
The main risk comes from the portion of energy absorbed by cells. This energy causes ionization, a process that can break apart complex organic molecules such as proteins, nucleic acids (DNA), and enzymes. Such damage can interfere with normal cell function and, in severe cases, lead to cell death.
Tissues with rapidly dividing cells are especially vulnerable, including:
Reproductive organs (gonads)
Bone marrow
The thyroid gland
The eye lens (where exposure can contribute to cataract formation)
Where the Risk Comes From for Medical Staff
During a procedure, the patient receives the direct radiation from the X-ray tube. For doctors, nurses, and technicians, the primary risk does not come from the direct beam, but from scattered radiation.
When X-ray enter the patient's body:
~80–90% are absorbed
~10–20% scatter outward
~1% pass through to the detector
It is the scattered radiation that fills the operating room and exposes the surgical team. The highest intensity of scatter typically travels back toward the X-ray tube.
Key Strategies to Reduce Radiation Exposure
Understanding how radiation behaves allows the surgical team to greatly reduce their exposure. Four essential safety practices are:
Place the Tube Under the Table (for supine patients):
Positioning the X-ray tube beneath the operating table lets the patient's body act as a shield, significantly reducing scatter toward staff.
Stand on the Detector Side During Lateral Imaging:
When imaging from the side, always place the tube on the side without staff. The entire team should stay on the detector or intensifier side, where scatter is lowest.
Keep the Detector Close to the Patient:
Minimizing the gap between the detector and the patient reduces scatter, improves image quality, and allows for a lower radiation dose.
Collimate and Center the Beam:
Properly centering the target area and using collimation to limit the beam to the smallest necessary field reduces both patient dose and the amount of scattered radiation.
By consistently following these principles, medical professionals can use X-ray imaging safely and effectively, protecting themselves and their patients from unnecessary radiation exposure.
