Department of Trauma, 27243University Hospital Zurich, University Hospital Zurich, Zurich, Switzerland.
Department of Orthopaedics, Trauma and Plastic Surgery, University Hospital of Leipzig, Leipzig, Germany.
Acta Radiol. 2022 Aug;63(8):1062-1070. doi: 10.1177/02841851211029077. Epub 2021 Jul 6.
Carbon-reinforced PEEK (C-FRP) implants are non-magnetic and have increasingly been used for the fixation of spinal instabilities.
To compare the effect of different metal artifact reduction (MAR) techniques in magnetic resonance imaging (MRI) on titanium and C-FRP spinal implants.
Rod-pedicle screw constructs were mounted on ovine cadaver spine specimens and instrumented with either eight titanium pedicle screws or pedicle screws made of C-FRP and marked with an ultrathin titanium shell. MR scans were performed of each configuration on a 3-T scanner. MR sequences included transaxial conventional T1-weighted turbo spin echo (TSE) sequences, T2-weighted TSE, and short-tau inversion recovery (STIR) sequences and two different MAR-techniques: high-bandwidth (HB) and view-angle-tilting (VAT) with slice encoding for metal artifact correction (SEMAC). Metal artifact degree was assessed by qualitative and quantitative measures.
There was a much stronger effect on artifact reduction with using C-FRP implants compared to using specific MRI MAR-techniques (screw shank: < 0.001; screw tulip: < 0.001; rod: < 0.001). VAT-SEMAC sequences were able to reduce screw-related signal loss artifacts in constructs with titanium screws to a certain degree. Constructs with C-FRP screws showed less artifact-related implant diameter amplification when compared to constructs with titanium screws ( < 0.001).
Constructs with C-FRP screws are associated with significantly less artifacts compared to constructs with titanium screws including dedicated MAR techniques. Artifact-reducing sequences are able to reduce implant-related artifacts. This effect is stronger in constructs with titanium screws than in constructs with C-FRP screws.
碳纤维增强聚醚醚酮（C-FRP）植入物为非磁性材料，已越来越多地用于脊柱失稳的固定。
比较不同磁共振成像（MRI）金属伪影降低（MAR）技术对钛和 C-FRP 脊柱植入物的影响。
将棒-椎弓根螺钉结构安装在绵羊尸体脊柱标本上，并分别用 8 个钛制椎弓根螺钉或由 C-FRP 制成的椎弓根螺钉和超薄钛壳标记。在 3T 扫描仪上对每种配置进行 MRI 扫描。MR 序列包括横轴位常规 T1 加权涡轮自旋回波（TSE）序列、T2 加权 TSE 序列和短反转恢复（STIR）序列，以及两种不同的 MAR 技术：高带宽（HB）和视角倾斜（VAT），用于金属伪影校正的切片编码（SEMAC）。通过定性和定量评估评估金属伪影程度。
与使用特定的 MRI MAR 技术相比，使用 C-FRP 植入物对降低伪影的效果要强得多（螺钉杆： < 0.001；螺钉帽： < 0.001；棒： < 0.001）。VAT-SEMAC 序列能够在一定程度上降低钛制螺钉结构中的螺钉相关信号丢失伪影。与钛制螺钉结构相比，C-FRP 螺钉结构的伪影相关植入物直径放大程度较小（ < 0.001）。
与钛制螺钉结构相比，C-FRP 螺钉结构的伪影明显较少，包括专用的 MAR 技术。降低伪影的序列能够降低植入物相关的伪影。这种效果在钛制螺钉结构中比在 C-FRP 螺钉结构中更强。
