Comparison of Image Qualities of 80 kVp and 120 kVp CT Venography Using Model-Based Iterative Reconstruction at Same Radiation Dose

Purpose: To compare image qualities of 80 kVp CT venography (CTV) and 120 kVp CTV by model-based iterative reconstruction (MBIR) at the same radiation dose. Materials and Methods: Sixty-nine patients that underwent CTV using 80 kVp (36 patients, group 1) or 120 kVp (33 patients, group 2) with MBIR at the same radiation dose were enrolled, and objective and subjective image qualities were assessed independently by two radiologists. Results: Mean vascular enhancement and contrast-to-noise ratio were significantly higher in group 1 than in group 2 for inferior vena cavas, femoral veins, and popliteal veins (p < 0.001), and there was significantly lower objective image noise in group 1 (p < 0.001). Subjective analysis revealed image quality was significantly higher in group 1 and image noise was significantly higher in group 2 (p < 0.001). Mean dose-length products was not significantly lower in group 1 (356.1 ± 153.7 mGy cm) than in group 2 (370.1 ± 77.1 mGy cm) (p = 0.635). Conclusion: CTV at 80 kVp with MBIR is a better protocol than CTV at 120 kVp with MBIR at the same radiation dose.