Computed tomography (CT) of the chest at less than 1 mSv: an ongoing prospective clinical trial of chest CT at submillisievert radiation doses with iterative model image …

PurposeTo assess lesion detection and diagnostic confidence of computed tomography (CT) of the chest performed at less than 1 mSv with 2 iterative reconstruction (IR) techniques.Materials and MethodsTen patients gave written informed consent for the acquisitions of images at submillisievert dose (0.9 mSv), in addition to clinical standard-dose (SD) chest CT (2.9 mSv). Submillisievert images were reconstructed with iDose 4 and iterative model reconstruction (IMR). Two radiologists assessed lesion detection, margins, diagnostic confidence, and visibility of small structures. Objective noise and noise spectral density were measured.ResultsLesion detection was identical for standard-dose filtered back projection (FBP), submSv iDose 4, and submSv IMR. Lesion margins were better seen for 30% of detected lung lesions with submSv IMR compared to standard-dose FBP and submSv iDose 4 (P< 0.05). Visibility of …