Radiation dose reduction by adjusting bolus tracking parameters in a 320-detector row scanner

Area of Science:

• Radiology
• Medical Imaging
• Radiation Dose Reduction

Background:

• Bolus tracking (BT) is crucial for optimizing contrast delivery in coronary computed tomography angiography (CTA).
• The impact of BT parameter optimization on total effective radiation dose (ERD) in CTA has been under-explored.
• Reducing ERD is a key objective in modern medical imaging.

Purpose of the Study:

• To investigate whether adjusting BT parameters can effectively reduce ERD in CTA.
• To evaluate the impact of different BT delay and intermittent scan timings on radiation dose.
• To assess if dose reduction affects image quality.

Main Methods:

• 289 adult patients undergoing CTA were allocated to four BT protocols with varying delay and intermittent scan times.
• Protocols differed in delay (10s vs. 15s) and intermittent scan frequency (1s vs. 2s).
• Image quality and total ERD were assessed for each protocol.

Main Results:

• Overall ERD in BT was significantly lower than in standard acquisition (0.32 ± 0.14 mSv vs. 6.06 ± 0.66 mSv).
• ERD varied significantly across BT protocols (p < 0.001), with protocol D (15s delay, 2s intermittent scans) showing the lowest dose (0.23 ± 0.09 mSv).
• Protocol D demonstrated the highest reduction in ERD (β = -0.33, p = 0.004) without compromising image quality.

Conclusions:

• Adjusting bolus tracking parameters by increasing delay time and decreasing scan frequency reduces radiation dose in CTA.
• Optimized BT protocols significantly lower ERD compared to standard methods.
• Radiation dose reduction is achievable without sacrificing diagnostic image quality in CTA.