多回波化学位移编码水脂成像技术定量评估退行性脊柱侧凸患者多裂肌退行性变的初步研究

Evaluating multifidi degeneration in patients with degenerative scoliosis using multi-echo Dixon sequence: a preliminary study

摘要:

目的： 运用3.0 T磁共振（magnetic resonance，MR）多回波化学位移编码水脂成像（chemical shift-encoding water-fat imaging，Dixon）技术，定量评估退行性脊柱侧凸（degenerative scoliosis，DS）患者多裂肌（multifidi，MF）退行性变与非畸形者的差异性。方法： 分析陆军军医大学第一附属医院2018年7月至2020年6月行3.0 T MR腰椎Dixon序列扫描的检查者60例，30例DS患者为DS组，30例非DS患者为对照组。2名放射医师采用双盲法测量2组人群Dixon序列中腰椎4/5椎间盘（L4/5）层面MF脂肪浸润度（fat infiltration，FI）、横截面积（cross sectional area，CSA）及椎间盘面积，比较其一致性。计算双侧MF脂肪含量均值百分比（FI%），双侧MF相对CSA（relative CSA，RCSA）、双侧MF功能性CSA（functional CSA，FCSA）、双侧MF面积不对称率（asymmetry ratio of area，AAA）、双侧脂肪浸润度不对称指数（asymmetry ratio of fat infiltration index，AAFI）的差异性，并比较2组奥斯维斯残疾指数（Oswestry disability index，ODI）、腰和下肢疼痛视觉模拟评分（visual analogue scale scores，VAS）、腰罗兰莫里斯功能障碍调查（Roland-Morris disability questionnaire，RMD）问卷评分的差异性，受试者操作特征曲线（receiver operating characteristic curve，ROC）法计算双侧MF FI%、AAFI、ODI、RMD，腰椎和下肢VAS总和评分曲线下面积。结果： 2位独立观察者对多裂肌的CSA、FI%及椎间盘面积的重复测量具有较好的一致性（ICC>0.9）；DS组与对照组双侧MF FI%、RCSA、FCSA、AAFI有统计学差异（P<0.05）；ODI、VAS、RMD有统计学差异（P<0.05）；2组双侧MF FI%、AAFI、ODI、RMD、VAS的ROC曲线下面积分别为0.818、0.754、0.984、0.947、0.933。结论： 多回波Dixon序列双侧MF FI%、AAFI能定量反映DS患者的疼痛加重度情况与生活质量下降程度，并与患者的临床评估指标有良好的一致性，与对照组有显著鉴别效能。

Abstract:

Objective: To quantitatively evaluate the multifidi (MF) degeneration by using multi-echo 3.0 T magnetic resonance (MR) chemical shift-encoding water-fat imaging (Dixon) sequence in patients with degenerative scoliosis (DS) and contrast with those in non-DS volunteers. Methods: Sixty subjects who underwent 3.0 T MR lumbar examination using Dixon sequence from July 2018 to June 2020 in our hospital were included in this study, with thirty DS patients (DS group) and thirty non-DS volunteers (control group). The fat infiltration (FI) and cross sectional area (CSA) at the MF on levels L4 through L5 (L4/5) of all subjects were measured by two radiologists using the double-blind method to compare consistency. The mean percentage of FI (FI%), relative CSA (RCSA), functional CSA (FCSA), asymmetry ratio of area (AAA) and asymmetry ratio of fat infiltration index (AAFI) of bilateral MF at L4/5 were calculated, and the differences were compared between DS and control groups. The statistical significance of Oswestry disability index (ODI), sum of visual analogue scale scores (VAS) at lumbar and legs and Roland-Morris disability questionnaire (RMD) scores between DS patients and control volunteers were also compared. Receiver operating characteristic (ROC) curve of FI%, AAFI, ODI, RMD and VAS were calculated. Results: Interobserver agreement of FI%and CSA was excellent between the two radiologists (ICC>0.9). The FI%, RCSA, FCSA and AAFI of bilateral MF were statistically significant (P<0.05). ODI, VAS and RMD obtained from DS group showed a significantly higher scores than those from control group. Areas of FI%, AAFI, ODI, RMD and VAS under the ROC curve were respectively 0.818, 0.754, 0.984, 0.947 and 0.933.Conclusion: The FI%and AAFI of bilateral MF at L4/5 level calculated by multi-echo Dixon image will reflect the worse pain and quality of life of DS patients, which has good consistency with clinical factors, with a valuable diagnostic efficacy to identify non-DS volunteers.