Using SEMAC at 3 T MR to evaluate spinal metallic implants and peripheral soft tissue lesions

We aimed to assess the usefulness of slice-encoding metal artifact correction (SEMAC) for the evaluation of spinal metallic implants and peripheral soft tissue lesions at 3T magnetic resonance. Twenty-seven patients with spinal metal implants underwent both SEMAC and high bandwidth (HiBW) based sequences scanning for reduction artifacts. The area size and maximum longitude of artifacts, the peri-prosthetic soft tissue, and metal visualization were assessed by 2 independent doctors, as well as the lesions signs were reviewed by 2 senior readers. A paired 2-tailed t-test and McNemar test were used for statistical analysis. The size of artifacts on SEMAC images decreased by 37% and 24%, and the scores are higher than that on HiBW images. T(1) weighted (T(1)W)-SEMAC acquired the highest score in metal prosthesis visualization, while short tau inversion recovery SEMAC showed more signs of lesions than clinical HiBW group. SEMAC effectively reduces the metal artifacts and is useful for assessing soft tissue lesions.