Comparison of quantitative measurements of four manufacturer’s metal artifact reduction techniques for CT imaging with a self-made acrylic phantom

Abstract

BACKGROUND: Metal artifact reduction (MAR) techniques can improve metal artifacts of computed tomography (CT) images. OBJECTIVE: This work focused on conducting a quantitative analysis to compare the effectiveness of four commercial MAR techniques on three types of metal implants (hip implant, spinal implant, and dental filling) with a self-made acrylic phantom. METHODS: A cylindrical phantom was made from acrylic with a groove in the middle, and then three types of metal implants were placed in the groove. The phantom was scanned by four CT scanners and four commercialized MAR techniques were used to analyze the images. The techniques used were single-energy metal artifact reduction (SEMAR, Canon), smart metal artifact reduction software (Smart-MAR, GE), iterative metal artifact reduction (IMAR, Siemens), and metal artifact reduction for orthopedic implants (OMAR, Philips). Quantitative analysis methods included objective and subjective analysis. RESULTS: The expected value of SEMAR, Smart-MAR, IMAR, and OMAR were 36.6, 37.8, 5.0, and 2.3, respectively. SEMAR and Smart-MAR achieved optimal results. CONCLUSION: This study successfully evaluated the effects of four commercial MAR techniques on three types of metal implants in a phantom. All MAR techniques effectively reduced metal artifacts, but the effect was not significant with dental fillings due to high-density material.

Quantitative analysis of metal artifact reduction in total hip arthroplasty using virtual monochromatic imaging and orthopedic metal artifact reduction, a phantom study

“…Our quantitative analysis using a THA phantom shows that high energy VMI with O-MAR results in the strongest metal artifact reduction, and this is supported by studies incorporating subjective assessment by radiologists [5][6][7] and by studies incorporating quantitative assessment of metal artifact reduction [5,7,23]. However, these studies used General Electric (GE) or Siemens systems to extract VMI with metal artifact reduction software, while we used a Philips system to extract VMI with O-MAR.…”

Effectiveness of orthopedic metal artifact reduction among patients undergoing computed tomography at a tertiary setting – A cross-sectional study

“…Two Kiloelectronvolt levels for VME images for MAR for various types of metal implants are relatively high and range between 77 and 141 keV. 7 The previous studies by Patel and Marin, 8 Zhang et al, 9 and Chou et al, 10 have demonstrated the effectiveness of various reconstruction techniques used in clinical practice in reducing metal artifacts, such as MAR algorithms, model-based iterative reconstruction, iterative MAR (iMAR, pre-commercial version, Siemens Healthcare), single-energy MAR, and virtual monochromatic imaging (VMI). 11 The first commercialized iterative reconstruction method that can be applied to conventional CT data is the MAR algorithm for orthopedic implants (orthopedic metal artifact reduction [O-MAR], Philips Healthcare).…”

Synthetic Megavoltage Cone Beam Computed Tomography Image Generation for Improved Contouring Accuracy of Cardiac Pacemakers

“…GANs have also been investigated for multi-modal medical image generation (e.g., MR to CT, CT to PET, or CBCT to CT), dose reduction, and image artifact removal [14][15][16][17][18]. Gomi et al reported adequate artifact removal in digital tomosynthesis at up to 55% radiation dose reduction after the extensive model optimization of GAN architectures to minimize the mean squared error and structural similarity [19]. Another study by Liao et al reduced metal artifacts on CT and CBCTs by correcting the affected regions through joint projection-sinogram correction and adversarial learning [20].…”