Optimization of X-ray acquisition parameters for reduced radiation exposure while maintaining 2D-DSA image quality during lower limb angioplasty.

BACKGROUND

Achieving optimal image quality with minimal radiation exposure allows operators to accurately assess and treat target lesions during percutaneous transluminal angioplasty (PTA) without being subjected to increased radiation risk. Depending on clinical needs, imaging protocols are optimized and evaluated. This study aims to compare two imaging protocols-conventional dose protocol (CDP) and low dose protocol (LDP)-to evaluate the impact of fine-tuned X-ray acquisition parameters (detector entrance dose, copper filtration, tube voltage) and post-processing parameters (edge enhancement, window contrast).

METHODS

Thirty patients who underwent PTA between February to April 2021 were retrospectively reviewed. A representative two-dimensional digital subtraction angiography (2D-DSA) image was selected for both image quality and radiation dose comparison. Radiation dose was assessed using dose area product per frame (DAP/frame) and air kerma per frame (AK/frame) as normalized metrics to exclude effect of procedural duration. Each image was assessed quantitatively by measuring contrast-to-noise ratio (CNR) and qualitatively by two experienced vascular surgeons with a 5-point Likert scale.

RESULTS

Radiation dose with LDP showed a significant reduction in DAP/frame (2.49±1.65 µGy·m2 in CDP vs. 0.48±0.42 µGy·m2 in LDP) and AK/frame (0.10±0.07 µGy in CDP vs. 0.02±0.02 µGy in LDP). CNR was higher with LDP than with CDP (0.83±0.81 in CDP vs. 2.99±2.44 in LDP). Qualitative image quality assessment demonstrated no significant differences between protocols across all criteria (P>0.05).

CONCLUSIONS

Parametric optimization of X-ray acquisition protocols in angiography system can potentially reduce radiation exposure without compromising image quality.