Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S Kings Highway Blvd Campus Box 8131, St Louis, MO, 63110, USA.
Department of Radiology, LSUHSC-Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
Emerg Radiol. 2021 Jun;28(3):581-588. doi: 10.1007/s10140-020-01880-4. Epub 2021 Jan 15.
To evaluate the safety and image quality of extremity MR examinations performed with two MR conditional external fixators located in the MR bore.
Single-center retrospective study of a prospectively maintained imaging dataset that evaluated MR examinations of extremities in patients managed with external fixations instrumentation and imaged on a single 1.5T MR scanner. The fixation device was one of two MR-conditional instrumentation systems: DuPuy Synthes (aluminum, stainless steel, carbonium and Kevlar) or Dolphix temporary fixation system (PEEK-CA30). Safety events were recorded by the performing MR radiologic technologist. A study musculoskeletal radiologist assessed all sequences to evaluate for image quality, signal- and contrast-to-noise ratios (SNR/CNR), and injury patterns/findings.
In the 13 men and 9 women with a mean age of 42 years (range 18 to 72 years), most patients (19/22 patients; 86%) were involved with trauma resulting in extremity injury requiring external fixation. MR examinations included 19 knee, 2 ankle, and 1 elbow examinations. There were no adverse safety events, heating that caused patient discomfort, fixation dislodgement/perturbment, or early termination of MR examinations. All examinations were of diagnostic quality. Fat-suppressed proton density sequences had significantly higher SNR and CNR compared to STIR (p = 0.01 to 0.04). The lower SNR of STIR and increased quality of fat-suppressed proton density during the study period led to the STIR sequence being dropped in standard MR protocol.
MR of the extremity using the two study MR conditional external fixators within the MR bore is safe and feasible.
评估两种置于磁共振（MR）磁体孔内的 MR 兼容外固定器进行四肢 MR 检查的安全性和图像质量。
对使用外固定器器械进行管理并在单台 1.5T MR 扫描仪上成像的患者进行前瞻性维护成像数据集的单中心回顾性研究。固定装置为两种 MR 兼容器械系统之一：捷迈邦美（铝、不锈钢、碳纤维和凯夫拉）或 Dolphix 临时固定系统（PEEK-CA30）。执行磁共振放射技师记录安全性事件。一位研究肌肉骨骼放射科医生评估所有序列以评估图像质量、信号和对比噪声比（SNR/CNR）以及损伤模式/发现。
在 13 名男性和 9 名女性（平均年龄 42 岁，范围 18 至 72 岁）中，大多数患者（22 名患者中的 19 名；86%）因创伤导致四肢受伤需要外固定。MR 检查包括 19 个膝关节、2 个踝关节和 1 个肘关节检查。没有发生不良安全事件、引起患者不适的加热、固定器移位/干扰或 MR 检查提前终止。所有检查均具有诊断质量。与短反转时间反转恢复（STIR）序列相比，脂肪抑制质子密度序列具有更高的 SNR 和 CNR（p = 0.01 至 0.04）。STIR 序列的 SNR 较低，在研究期间脂肪抑制质子密度的质量提高，导致 STIR 序列在标准 MR 协议中被删除。
在 MR 磁体孔内使用两种研究型 MR 兼容外固定器进行四肢 MR 检查是安全且可行的。
