Objective  To evaluate the application value of CT metal artifact correction technology (MAC^TM) in CT review after total hip replacement.

  Methods   A total of 72 patients who underwent CT re-examination after total hip replacement from December 2018 to March 2020 were enrolled, and the original data were reconstructed by filter backup projection （FBP） and MAC. Select three identical levels in the two sets of reconstructed images and place the same ROI. The selected levels were the initial level, central level, and lower edge of acetabulum. Measure the CT and noise (SD) of metal high and low density artifacts of the three levels area, as well as metal hip joint space, metal para-bone tissue, muscle, bladder and subcutaneous fat, and calculate the average value. Subcutaneous fat value was used as a reference to calculate the SNR and CNR of metal implant para-bone tissue, muscle and bladder. Two radiologists scored the two groups of reconstructed images using blinded method, Kappa’s test was used to compare the homogeneity.

  Results  There were differences between the two groups of reconstructed images in high- and low-density artifact areas, joint gap CT values, and image noise. Compared with the FBP group, the CT value of the high-density area and the joint space of the MAC group decreased, the CT value of the low-density area increased, and the noise value of each area decreased. The SNR and CNR of metal adjacent bone tissue, muscle and bladder were higher in the MAC group than those in the FBP group, and the difference was statistically significant (P<0.05). The difference in subjective scores between the two groups was statistically significant (Z=−6.564, P<0.05). 2 radiologists had moderate consistency with Kappa value of 0.72 on FBP group, and good consistency with Kappa value of 0.85 on MAC group.

  Conclusion  MAC^TM in CT review after total hip replacement can reduce metal artifacts, make the joint space more clear, and improve the quality of CT images.