三维各向同性磁共振成像分析踝关节解剖结构

目的对比各向同性三维快速自旋回波（3 dimensional fast spin echo, 3D-FSE）和三维快速场回波（3 dimensional fast field
echo, 3D-FFE）及二维快速自旋回波（2 dimensional fast spin echo, 2D-FSE）对踝关节解剖结构显示的特点。方法随机选10名
志愿者进行各向同性3D-FSE、3D-FFE及2D-FSE序列磁共振扫描以及三维重建，并测量各组织的信噪比（signal-to-noise ratio,
SNR）、对比信噪比（contrast-to-noise ratio, CNR），用5 分利克特表（5-point Likert scale）评估各序列各组织的成像质量。结果
在各组织中的3D-FSE 序列SNR最高，在软骨、肌肉、肌腱中其次为3D-FFE 序列；软骨-骨髓、肌肉-肌腱、关节液-肌腱中的
3D-FSE的CNR最高，其次为3D-FFE，各序列间具有统计学差异（P<0.05）。主观评估三种序列踝关节软骨的成像质量，各序列
间有统计学差异（P<0.05），3D-FFE成像质量最好，其次为3D-FSE。主观评估韧带中3D-FSE、2D-FSE序列均优于3D-FFE序列
（P<0.05）；主观评估肌腱中，除腓短肌腱外，其余肌腱都有统计学差异（P<0.05），且都是3D-FSE成像质量最好，其次为2D-FSE
序列。结论各向同性3D-FSE 序列具有最高的SNR、CNR，能任意平面重建，扫描时间短，可全面评估复杂关节的解剖结构，广
泛应用临床。

Three-dimensional isotropic magnetic resonance imaging of the ankle joint

Objective To compare the image quality of isotropic 3-dimensional fast spin echo (3D-FSE), 3D fast field echo
(3D-FFE), and 2D fast spin echo (2D-FSE) sequences in magnetic resonance imaging (MRI) of the anatomical structure of the
ankle joint. Methods The ankle joints of 10 healthy volunteers were examined with isotropic 3D-FSE, 3D-FFE and 2D-FSE
sequences using a 1.5T MR scanner and 3D reconstruction. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of
the tissues were measured. Two radiologists evaluated the image quality of the 3 sequences using a 5-point Likert scale in a
double-blinded manner. Results The 3D-FSE sequences resulted in the highest SNRs for all the tissues and the highest CNRs
for differentiation between cartilage and marrow, between muscle and tendon, and between tendon and fluid. In the
estimation of image quality for cartilages, 3D-FFE had the highest score followed by 3D-FSE, and the latter had the highest
score among the 3 sequences in displaying the tendon. Conclusion 3D-FSE sequence has a high performance in displaying the
anatomical structures of complex joints especially for cartilage, ligament, and tendon tissues.