Iterative algorithms for artifact reduction in computed tomography

Computed tomography (CT) acquisition should be performed following the ALARA principle: keeping patient radiation exposure as low as reasonably achievable. Reconstruction with filtered backprojection is still the standard in CT. Recently, iterative reconstruction techniques have become available, using a different approach for image reconstruction. A similar approach is used for iterative metal artifact reduction. Compared to filtered backprojection, iterative reconstruction yields improvements in image quality and reduces image noise. Using iterative reconstruction allows the reduction of patient radiation exposure by up to 80%, depending on the used algorithm and the clinical task at hand. With the help of iterative metal artifact reduction, images of diagnostic quality can be acquired despite metal implants. Iterative reconstruction should be used to reduce patient radiation exposure in accordance with the clinical requirements. The use of iterative metal artifact reduction is recommended. (orig.)