Huber, Adrian ThomasAdrian ThomasHuberLandau, JuliaJuliaLandauEbner, LukasLukasEbnerBütikofer, Yanik FrederikYanik FrederikBütikoferLeidolt, LarsLarsLeidoltBrela, BarbaraBarbaraBrelaMay, MichelleMichelleMayHeverhagen, JohannesJohannesHeverhagen0000-0002-5416-6650Christe, AndreasAndreasChriste2024-10-242024-10-242016-10https://boris-portal.unibe.ch/handle/20.500.12422/148839OBJECTIVE To investigate the detection rate of pulmonary nodules in ultralow-dose CT acquisitions. MATERIALS AND METHODS In this lung phantom study, 232 nodules (115 solid, 117 ground-glass) of different sizes were randomly distributed in a lung phantom in 60 different arrangements. Every arrangement was acquired once with standard radiation dose (100 kVp, 100 references mAs) and once with ultralow radiation dose (80 kVp, 6 mAs). Iterative reconstruction was used with optimized kernels: I30 for ultralow-dose, I70 for standard dose and I50 for CAD. Six radiologists examined the axial 1-mm stack for solid and ground-glass nodules. During a second and third step, three radiologists used maximum intensity projection (MIPs), finally checking with computer-assisted detection (CAD), while the others first used CAD, finally checking with the MIPs. RESULTS The detection rate was 95.5 % with standard dose (DLP 126 mGy*cm) and 93.3 % with ultralow-dose (DLP: 9 mGy*cm). The additional use of either MIP reconstructions or CAD software could compensate for this difference. A combination of both MIP reconstructions and CAD software resulted in a maximum detection rate of 97.5 % with ultralow-dose. CONCLUSION Lung cancer screening with ultralow-dose CT using the same radiation dose as a conventional chest X-ray is feasible. KEY POINTS • 93.3 % of all lung nodules were detected with ultralow-dose CT. • A sensitivity of 97.5 % is possible with additional image post-processing. • The radiation dose is comparable to a standard radiography in two planes. • Lung cancer screening with ultralow-dose CT is feasible.enComputed tomographyDiagnostic performance with low radiation dosageLung adenocarcinomaPulmonary nodule detectionUltralow-dose acquisition600 - Technology::610 - Medicine & healthPerformance of ultralow-dose CT with iterative reconstruction in lung cancer screening: limiting radiation exposure to the equivalent of conventional chest X-ray imaging.article10.7892/boris.940542681367010.1007/s00330-015-4192-3