Abstract: Objective: This study evaluated the value of the Philips Orthopedic Metal Artifact Reduction (O-MAR) algorithm for reducing metal implant phantom following unicompartmental knee arthroplasty. Methods: A retrospective study was conducted on 100 patients who underwent unicompartmental knee arthroplasty at the First Hospital of Hebei Medical University from January to October 2024. All patients underwent CT using a Philips Incisive 64-slice scanner, and the post-scan data were reconstructed using O-MAR to generate images with and without O-MAR correction (O-MAR and non-O-MAR images). The signal-to-noise ratio (SNR) and artifact index (AI) of periarticular bone and muscle tissues in both reconstructed images were compared to evaluate phantom formation. Thin-section images were reconstructed using a GE AW4.7 workstation, followed by measurements of linear streak artifacts and the total volumes of bone tissue and prostheses in each group. The volume reduction due to phantom suppression was calculated as the difference between non-O-MAR and O-MAR volumes. Two senior radiologists conducted subjective evaluations of both cross-sectional and 3D imaging quality. Results: The signal-to-noise ratios (SNRs) of bone and muscle tissues were significantly higher in the O-MAR images than in the non-O-MAR images, whereas the artifact index (AI) was significantly lower in the O-MAR group. The O-MAR group demonstrated significantly higher subjective knee joint scores than the non-O-MAR group. Three-dimensional imaging volumes were measured as (259.59±70.76) cm³ for the non-O-MAR group and (203.02±58.37) cm³ for the O-MAR group, with a statistically significant difference. The three-dimensional image volume in the O-MAR group was 21.79% less than that in the non-O-MAR group. Conclusion: In patients undergoing unicompartmental knee arthroplasty, the O-MAR algorithm effectively reduced metal artifacts, improved image quality, and enhanced visualization of the surrounding tissues.