C J Q Yap, B J Kim, Z Resurreccion, Q T Teo, N Z P Ng, A C K Chia, H Y Yap, T T Chong
The adoption of OPTIQ protocol can bring about radiation-dose reduction for both patients and healthcare workers during lower limb angioplasty without compromising diagnostic image quality, which is in line with As Low As Reasonably Achievable (ALARA) principles.
AIM: Radiation exposure during peripheral vascular intervention poses potential deterministic and stochastic risks in the long run to patients and operators. Thus, it is important to optimise radiation dose without compromising on image quality. OPTIQ, a novel contrast-to-noise ratio (CNR)-driven exposure control, is prospectively evaluated against conventional dose protocol (CDP) to determine differences in radiation dose and image quality.
MATERIALS AND METHODS: Forty lower limb angioplasty cases between April 2023 and March 2025 were randomly assigned to either CDP or OPTIQ protocol for prospective evaluation. Primary outcomes included radiation dose measured by dose-area product (DAP) and air kerma (AK) for patients and scattered radiation exposure for operators using real-time dosimeters. Secondary outcomes assessed subjective image quality using 5-point Likert scales for contrast, brightness, sharpness, and device visualisation.
RESULTS: Patient demographics were comparable between groups. OPTIQ demonstrated significant radiation dose reduction compared to CDP: total DAP (412.8 ± 318.2 vs 1,284.5 ± 841.2 μGym2, P<0.001), two-dimensional (2D) angiography DAP (132.0 ± 92.5 vs 1,059.3 ± 640.4 μGym2, P<0.001), and total AK (19.9 ± 16.9 vs 55.0 ± 45.3 mGy, P<0.005). Total radiation dose reduced by approximately 60% with OPTIQ. Operator radiation exposure was lower with OPTIQ (0.138 ± 0.135 vs 0.362 ± 0.632 μSv/sec, P=0.288), though not statistically significant. Subjective image quality assessments showed no significant differences between protocols across all parameters (P>0.05), with both protocols providing diagnostically acceptable images.
CONCLUSION: The adoption of OPTIQ protocol can bring about radiation-dose reduction for both patients and healthcare workers during lower limb angioplasty without compromising diagnostic image quality, which is in line with As Low As Reasonably Achievable (ALARA) principles.