Application of low-tube-voltage combined with adaptive iterative reconstruction in lower extremity computed tomography angiography

Objective: To investigate the feasibility of low-tube-voltage in combination with the three-dimensional adaptive iterative dose reduction (AIDR-3D) algorithm in performing lower extremity computed tomography angiography (CTA). Methods: A total of 60 patients suspicious of lower extremity arterial occlusion were randomized into control group (120 kV, n = 30) and experimental group (100 kV, n = 30). The CTA was undertaken with a 320-row scanner (Toshiba Aquilion ONE), and the images was reconstructed with filtered back projection (FBP) algorithm in control group and FBP as well as the AIDR-3D algorithm in experimental group. The subjective image quality, vascular density (VD), noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and dose length product (DLP) were compared between two groups. Results: The DLP was significantly lower in experimental group than that in control group [(503.5 ± 104.7) vs. (1099.4 ± 151.7)mGy·cm, t = 15.7, P < 0.05]. The images in experimental group with 100 kV and FBP protocol had significantly increased VD and noise (t = -3.13, -3.61, P < 0.05) than that in the control. The images in experimental group with AIDR-3D had significantly lower noise and higher SNR and CNR than that with FBP (t = 13.59, 2.14, P < 0.05), also significantly lower noise and significantly higher VD, SNR, and CNR than that in the control (t = -3.75, -4.19, -4.15, P < 0.05). Conclusions: Low-tube-voltage (100 kV) combined with AIDR-3D reconstruction could significantly improve the image quality and reduce radiation dose in lower extremity CTA with a 320-row CT scanner. Trial registration Chinese clinical trial registry, ChiCTR-DPD-16008054. (authors)