Radiation Dose Reduction During EVAR: Results from a Prospective Multicentre Study (The REVAR Study)

Area of Science:

• Medical Imaging
• Interventional Radiology
• Vascular Surgery

Background:

• Endovascular aneurysm repair (EVAR) is a standard treatment for abdominal aortic aneurysms (AAA).
• Minimizing radiation exposure during EVAR is crucial for patient and staff safety.
• Hybrid operating rooms offer advanced imaging capabilities for complex procedures.

Purpose of the Study:

• To evaluate intra-operative radiation exposure during EVAR using pre-operative computed tomographic angiography (CTA) fusion imaging.
• To assess the effectiveness of strict As Low As Reasonably Achievable (ALARA) guidelines in a modern hybrid room setting.
• To identify factors influencing radiation dose during EVAR procedures.

Main Methods:

• Prospective enrollment of 85 patients undergoing EVAR with bifurcated devices in six international centers between February and November 2016.
• Data collection included patient demographics (BMI), dose area product (DAP), cumulative air kerma (CAK), and contrast volume.
• Fusion imaging guidance was utilized in a hybrid room, adhering to ALARA principles.

Main Results:

• Median DAP was 14.7 Gy·cm², and median CAK was 107 mGy.
• Median contrast volume was 47 mL.
• Multivariable analysis identified collimation as the only significant factor associated with DAP reduction (p < .001).

Conclusions:

• Adherence to the ALARA principle and routine use of fusion imaging guidance for EVAR can achieve low radiation exposure.
• These findings demonstrate the feasibility of minimizing radiation dose in a real-world EVAR setting.
• Collimation is a key factor in reducing radiation dose during EVAR procedures.