Low-Dose Carotid Computed Tomography Angiography Using Pure Iterative Reconstruction

The aim of this study was to assess if a low-dose carotid computed tomography angiography (CTA) performed with pure iterative reconstruction (IR) is comparable to a conventional dose CTA protocol. Twenty patients were included. Radiation dose was divided into a low-dose acquisition reconstructed with pure IR and a conventional dose acquisition reconstructed with 40% hybrid IR. Dose, image noise, contrast resolution, spatial resolution, and carotid artery stenosis were measured. Mean effective dose was significantly lower for low-dose than conventional dose studies (1.84 versus 3.71 mSv; P < 0.001). Subjective image noise, contrast resolution, and spatial resolution were significantly higher for the low-dose studies. There was excellent agreement for stenosis grading accuracy between low- and conventional dose studies (Cohen κ = 0.806). A low-dose carotid CTA protocol reconstructed with pure IR is comparable to a conventional dose CTA protocol in terms of image quality and diagnostic accuracy while enabling a dose reduction of 49.6%.