MR 3D-PD-SPACE序列在评估正常踝关节韧带肌腱中的应用价值

目的：对比分析3D-SPACE序列及常规2D-TSE在对踝关节韧带及肌腱组织的显示价值。材料与方法21例健康自愿者进行3D-PD-SPACE三维各项同性矢状面扫描和2D-T2WI-FSE二维快速自旋回波各方位扫描，分别测量韧带、肌腱、软骨、关节液、肌肉的信噪比（SNR）以及关节液与软骨、脂肪与韧带、肌肉与肌腱的对比信噪比（CNR）。然后由2名资深MR医生对韧带、肌腱、软骨、关节液的显示效果、细节，图像质量（模糊、假象、容积效应、均匀性）等几方面进行评估，并用5分利克特量表（5-point Likert scale）来评估。结果 SPACE序列各组织SNR明显高于2D序列，两者有统计学意义（P〈0.01）；在关节液与软骨、关节液与韧带、关节液与脂肪、肌肉与肌腱CNR上3D高于2D的序列，两者同样有统计学意义（P〈0.01）。图像质量评估方面SPACE序列在距腓前韧带、跟腓韧带、内侧副韧带、纵向跟舟韧带薄层重建上比2D序列有更多优势，两者之间的差异有统计学意义（P〈0.05）；趾长伸肌腱、胟伸肌腱、腓长肌腱、腓短肌腱及趾长屈肌腱SPACE与2D比较薄层重建同样有统计学意义（P〈0.05）。结论3D-PD-SPASE质子加权各项同性踝关节扫描对踝关节韧带和肌腱的评估有重要价值，由于3D有多平面重建和曲面重建等特点能更好地满足临床的需要。

Application of MR 3D-PD-SPACE sequence in evaluation of ligaments and tendon of the ankle in healthy volunteer

Objective： To assess the value of MR 3D-SPACE sequence and conventional 2D-TSE sequence in evaluation of ligaments and tendon of the ankle in healthy volunteers. Materials and Methods：The ankles in 21cases were examined with MR imaging, including at coronal, sagittal, and axial postions 2D-fast spin echo-T2 Weighted imaging （2D-T2WI-FSE） and at sagittal position 3D-PD-SPACE. The signal noise ratio （SNR） of ligaments, tendon, cartilage, joint fluid and muscle, and the contrast noise ratio （CNR） of joint lfuid-cartilage, fat-ligament and muscle-tendon were calculated. 2 radiologists independently assessed depiction of ligaments cartilage, joint lfuid and tendons, as well as detection and grading of abnormalities of these structures （5-point Likert scale）. The ability in visualization of artifacts, signal homogenity, partial volume effects and faintness were evaluated. Results：SPASE sequence provided a signiifcantly higher SNR for all examined structures compared with conventional 2D sequence （P〈0.01）. SPASE sequence provided a significantly higher CNR for joint fluid-cartilage, joint fluid-ligament, joint fluid-fat and muscle-tendon compared with conventional 2D sequence （P〈0.01）. In imaging quality, SPACE sequence reconstructed imaging in displaying anterior talofibular ligament, calcaneofibular ligament, medial collateral ligament and calcaneonavicular ligament was better than conventional 2D sequence （P〈0.05）. At the same time, SPACE sequence reconstructed imaging in displaying extensor digitorum longus tendon, extensor pollicis longus, peroneus longus tendon, peroneus brevis tendon and lfexor digitorum longus tendon was better than conventional 2D sequence. There was a significant difference between SPACE and conventional 2D sequence （P〈0.05）. Conclusion：3D-PD-SPASE is a valuable technique for examination of ligament and tendon of ankle with multiplanar and curved reconstruction, which can provide more information for clinic.