Safety and interventional procedures

» What are the requirements for making a fluoroscopy facility safe?

The following requirements need to be met to ensure that a fluoroscopy facility is safe:

  • Registration of the fluoroscopy unit with the authority that regulates such facilities; 
  • Authorization of the facility by the appropriate national authority; Authorization is typically granted after consideration of room size and shielding, staff training and establishment of a quality control system for radiation protection; 
  • Conformity of the fluoroscopy system to the International Electrotechnical Commission (IEC) standards or appropriate national standards; 
  • Acceptance testing of the fluoroscopic system by a qualified medical physicist, and not only acceptance of the vendor’s reports; 
  • Periodic safety checks in accordance with the protocols established by the relevant professional body or relevant international organization; 
  • Monitoring of radiation doses to patients and staff and ensuring their conformity with the accepted standards. 

» Which fluoroscopic procedures have the potential to impart high radiation doses to patients?

Procedures such as endovascular aneurysm repair (EVAR), renal angioplasty, iliac angioplasty, kidney stent placement, therapeutic endoscopic retrograde cholangio-pancreatography (ERCP) and bile duct stenting and drainage have the potential to impart high radiation doses to patients, as much as procedures in interventional radiology and interventional cardiology, with a possibility of the skin dose exceeding one Gy. 

Any fluoroscopic procedure when prolonged may impart high radiation dose. Many of these procedures might be conducted outside the radiology department. Without appropriate staff training and implementation of radiation protection measures, dose to patients and risks may be high. These procedures require a higher level of optimization.

» Where might skin injury occur in fluoroscopic procedures?

On the skin surface at the entry port of the X-ray beam. The highest radiation dose to the skin occurs at the point of entry of the X-ray beam and that becomes the likely area for skin injury. If the beam is entering through the posterior surface (back of the patient), the entry port on the back will become the most likely area for radiation injury when the radiation dose to skin exceeds the dose threshold for skin injury.

The radiation intensity is typically 2 to 3 times higher for lateral and oblique views as compared to anteroposterior (AP) and posteroanterior (PA) views. Breast tissue in the beam will increase the thickness of the imaged part of the patient’s body and will lead to an increase in exposure parameters (kV, mA) and beam intensity. Thus one should avoid breast as the point of entry for the X-ray beam. On the other hand, the intensity of the exit beam is only about 1% of the intensity of the entrance beam. Directing the beam from the posterior surface rather than the anterior, whenever feasible and if it does not interfere with clinical purposes, will reduce the chances of breast skin injury during interventions in the chest region.