Effect of Spectral Filtering and Segmental X-ray Tube Current Switch-Off on Interventionalist's Scatter Exposure...

Area of Science:

• Medical Imaging
• Radiological Physics
• Radiation Safety

Background:

• Computed tomography (CT) dose optimization is critical for patient and operator safety, particularly in CT fluoroscopy (fluoro-CT) for real-time navigation.
• Interventional radiologists (IRs) face radiation exposure risks, necessitating effective protective measures, especially for head and neck regions.
• Standard radiation protection materials offer insufficient coverage for IRs during certain procedures.

Purpose of the Study:

• To evaluate the combined impact of spectral X-ray filtering with a tin filter (Sn filter) and partial-angle computed tomography (PACT) on radiation dose reduction.
• To quantify the dose reduction achieved at the IR's position in different body regions.
• To assess the specific contribution of the Sn filter to overall dose reduction.

Main Methods:

• Measurements of ambient dose rate (H˙*(10)) were performed in upper body (head/neck) and lower body (legs/feet) regions.
• A 120 kV X-ray tube voltage, 3 × 5.0 mm CT collimation, and 0.5 s rotation speed were used.
• Protocols involved comparisons with and without an Sn filter and with and without PACT (segmentally switching off X-ray tube current).

Main Results:

• The combination of Sn filter and PACT significantly reduced H˙*(10) in both body regions.
• In the upper body region, H˙*(10) decreased from 11.8 µSv/s to 6.1 µSv/s (p < 0.0001) with the combined protocol.
• The Sn filter alone contributed approximately 8% (0.5 µSv/s) to the dose reduction (p = 0.0005).

Conclusions:

• The combined use of an Sn filter and PACT effectively minimizes radiation exposure for interventional radiologists.
• This approach provides enhanced protection for IRs, particularly for the head and neck areas.
• The findings support the implementation of these techniques for improved radiation safety in fluoro-CT procedures.