Chest CT using spectral filtration: radiation dose, image quality, and spectrum of clinical utility

Objectives To determine the radiation dose, image quality, and clinical utility of non-enhanced chest CT with spectral filtration. Methods We retrospectively analysed 25 non-contrast chest CT examinations acquired with spectral filtration (tin-filtered Sn100 kVp spectrum) compared to 25 examinations acquired without spectral filtration (120 kV). Radiation metrics were compared. Image noise was measured. Contrast-to-noise-ratio (CNR) and figure-of-merit (FOM) were calculated. Diagnostic confidence for the assessment of various thoracic pathologies was rated by two independent readers. Results Effective chest diameters were comparable between groups ( P = 0.613). In spectral filtration CT, median CTDI vol , DLP, and size-specific dose estimate (SSDE) were reduced (0.46 vs. 4.3 mGy, 16 vs. 141 mGy*cm, and 0.65 vs. 5.9 mGy, all P