Departments of Stomatology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China.
Departments of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, China.
Sci Rep. 2022 May 19;12(1):8442. doi: 10.1038/s41598-022-12402-2.
This study aimed to compare MRI quality between conventional fast spin echo T weighted imaging (FSE TWI) with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) FSE TWI for patients with various porcelain fused to metal (PFM) crown and analyze the value of PROPELLER technique in reducing metal artifacts. Conventional FSE TWI and PROPELLER FSE TWI sequences for axial imaging of head were applied in participants with different PFM crowns: cobalt-chromium (Co-Cr) alloy, pure titanium (Ti), gold-palladium (Au-Pd) alloy. Two radiologists evaluated overall image quality of section in PFM using a 5-point scale qualitatively and measured the maximum artifact area and artifact signal-to-noise ratio (SNR) quantitatively. Fifty-nine participants were evaluated. The metal crown with the least artifacts and the optimum image quality shown in conventional FSE TWI and PROPELLER FSE TWI were in Au-Pd alloy, Ti, and Co-Cr alloy order. PROPELLER FSE TWI was superior to conventional FSE TWI in improving image quality and reducing artifact area for Co-Cr alloy (17.0 ± 0.2% smaller artifact area, p < 0.001) and Ti (11.6 ± 0.7% smaller artifact area, p = 0.005), but had similar performance compared to FSE TWI for Au-Pd alloy. The SNRs of the tongue and masseter muscle were significantly higher on PROPELLER FSE TWI compared with conventional FSE TWI (tongue: 29.76 ± 8.45 vs. 21.54 ± 9.31, p = 0.007; masseter muscle: 19.11 ± 8.24 vs. 15.26 ± 6.08, p = 0.016). Therefore, the different PFM crown generate varying degrees of metal artifacts in MRI, and the PROPELLER can effectively reduce metal artifacts especially in the PFM crown of Co-Cr alloy.
本研究旨在比较常规快速自旋回波 T 加权成像（FSE TWI）与带周期性旋转重叠平行线增强重建（PROPELLER）FSE TWI 对不同金属烤瓷熔附金属（PFM）冠患者的 MRI 质量，并分析 PROPELLER 技术在降低金属伪影方面的价值。对不同 PFM 冠（钴铬合金、纯钛、金钯合金）的患者进行头部轴向成像的常规 FSE TWI 和 PROPELLER FSE TWI 序列。两位放射科医生使用 5 分制对 PFM 节段的整体图像质量进行定性评估，并定量测量最大伪影面积和伪影信噪比（SNR）。共评估了 59 名参与者。金属冠伪影最少、图像质量最佳的是金钯合金、钛和钴铬合金。与常规 FSE TWI 相比，PROPELLER FSE TWI 可改善钴铬合金（伪影面积减少 17.0±0.2%，p<0.001）和钛（伪影面积减少 11.6±0.7%，p=0.005）的图像质量，减少伪影面积，而对金钯合金的效果与 FSE TWI 相似。与常规 FSE TWI 相比，PROPELLER FSE TWI 舌部和咬肌的 SNR 显著升高（舌部：29.76±8.45 比 21.54±9.31，p=0.007；咬肌：19.11±8.24 比 15.26±6.08，p=0.016）。因此，不同的 PFM 冠在 MRI 中产生不同程度的金属伪影，PROPELLER 可有效降低金属伪影，特别是在钴铬合金 PFM 冠中。
