IDEAL-IQ序列在冈上肌腱损伤后肩袖肌群脂肪浸润定量评估中的应用

Application of the IDEAL-IQ sequence in the quantitative evaluation of fat infiltration in the rotator cuff muscle group after supraspinatus tendon injury

目的采用非对称采集与迭代最小二乘估算法迭代水脂分离(iteraterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation,IDEAL-IQ)方法定量评估冈上肌腱损伤的严重程度与肩袖肌群脂肪浸润程度及受试者特征之间的关系。材料与方法回顾性分析2022年8月至2024年6月本院经肩关节镜证实的33例冈上肌腱部分撕裂患者及89例完全撕裂患者,均进行了常规MRI扫描及IDEAL-IQ序列扫描。由两名放射科医生分别对所有受试者的MRI图像进行独立评估,根据常规MRI图像的冈上肌腱损伤表现,将完全撕裂组的冈上肌腱按照Patte分型分为Patte 1型(Ⅱ级)、Patte 2型(Ⅲ级)、Patte 3型(Ⅳ级),将部分撕裂组定义为Ⅰ级。同时在斜矢状位上进行Goutallier分级及Thomazeau萎缩分级,并通过GE ADW 4.7工作站后处理软件在IDEAL-IQ序列生成的脂肪分数图像上测量冈上肌、冈下肌、肩胛下肌及小圆肌脂肪分数(fat fraction,FF)。用组内相关系数(intra-class correlation coefficient,ICC)及Kappa一致性检验评估观察者间及观察者内的一致性。采用Kruskal-Wallis H检验、单因素ANOVA检验分析FF值在不同分组之间的差异,组间两两比较用Bonferroni检验。采用Pear_(s)on相关性分析肩袖肌肉FF值与年龄、症状持续时间的相关性(相关系数r),Spearman相关性分析冈上肌腱损伤分级与肩袖肌群FF值、Goutallier分级及Thomazeau萎缩分级之间的相关性(相关系数r_(s))。结果(1)冈上肌、冈下肌、肩胛下肌的FF值在冈上肌腱损伤Ⅳ级中显著高于Ⅲ级,高于Ⅱ级和Ⅰ级,差异有统计学意义(P值分别为<0.001、<0.001、0.005);小圆肌的FF值在不同分级之间差异无统计学意义(P=0.073)。组内比较Ⅰ级和Ⅱ级的冈上肌、冈下肌、肩胛下肌、小圆肌FF值差异无统计学意义(P值分别为0.026、0.102);Ⅲ级和Ⅳ级的FF值差异有统计学意义(P<0.001)。(2)冈上肌、冈下肌、小圆肌的FF值与年龄呈中等相关(r值分别为0.381、0.339、0.349,P均<0.001),肩胛下肌的FF值与年龄呈弱相关(r=0.216,P=0.017);冈上肌、冈下肌、肩胛下肌FF值与症状持续时间呈中等程度相关(r分别为0.442、0.412、0.314,P均<0.001),小圆肌的FF值与症状持续时间呈弱相关(r=0.277,P=0.002);冈上肌腱损伤程度与冈上肌FF值呈显著相关(r_(s)=0.740,P<0.001),与冈下肌的FF值呈强相关性(r_(s)=0.596,P<0.001),与肩胛下肌、小圆肌的FF值呈弱相关(r_(s)分别为0.257、0.212,P值分别为0.004、0.019);冈上肌损伤程度分级与Goutallier分级、Thomazeau分级之间呈显著正相关(r_(s)分别为0.757、0.737,P均<0.001),且冈上肌FF值在Goutallier和Thomazeau的分级中差异具有统计学意义(P均<0.001)。结论3.0 T MR IDEAL-IQ序列能量化和客观评估肩袖肌群脂肪浸润程度,肩袖肌群脂肪浸润程度与冈上肌腱损伤分级呈正相关,与年龄、症状持续时间呈正相关。

Objective:The study utilized the iteraterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation(IDEAL-IQ)method to quantitatively evaluate the relationship between the severity of supraspinatus tendon injuries and the degree of fat infiltration of the rotator cuff muscle group and subject characteristics.Materials and Methods:A retrospective collection of 33 patients with partial supraspinatus tendon tears and 89 patients with complete tears confirmed by shoulder arthroscopy in our hospital from August 2022 to June 2024 was conducted.Conventional MRI and IDEAL-IQ sequence scans were performed.Two radiologists independently evaluated the MRI images of all subjects.Based on the supraspinatus tendon injury performance on conventional MRI images,the supraspinatus tendon in the fully tear group was divided into Patte 1(GradeⅡ),Patte 2(GradeⅢ),and Patte 3(GradeⅣ)according to the Patte classification.The partial tear group was defined as Grade I.At the same time,the Goutallier score and Thomazeau atrophy grading were performed on the oblique sagittal plane.Fat fraction(FF)of supraspinatus muscle,infraspinatus muscle,subscapularis muscle and teres minor muscle were measured on the fat fraction image generated by IDEAL-IQ sequence using GE ADW 4.7 workstation post-processing software.Intra-observer and intra-observer consistency were evaluated by intra-class correlation coefficient(ICC)and Kappa consistency test.Kruskal-Wallis H test and One-Way ANOVA test were used to analyze the differences of FF values among different groups,and Bonferroni test was utilized for pairwise comparison between groups.Pearson correlation was used to analyze the correlation between rotator cuff muscle FF value and age and duration of symptoms(the correlation coefficient is r).Spearman correlation was used to analyze the correlation between supraspinatus tendon injury grade and rotator cuff muscle FF value,Goutallier grade and Thomazeau atrophy grade(the correlation coefficient is rs).Results:(1)The FF values of the supraspinatus muscle,infraspinatus muscle,and subscapular muscle were significantly higher in GradeⅣthan those of the same muscles in GradeⅢ,GradeⅡand GradeⅠ,with statistical significance(P<0.001,<0.001,0.005,respectively).There was no significant difference in the FF value of the teres minor muscle among different grades(P=0.073).Results of intra-group comparision suggested that there was no significant difference in the FF values of the supraspinatus muscle,infraspinatus muscle,subscapularis muscle,and teres minor between GradeⅠand GradeⅡ(P=0.026,0.102).There was a significant difference in the FF value between GradeⅢand GradeⅣ(P<0.001).(2)The FF values of supraspinatus,infraspinatus,subscapularis and teres minor were moderately correlated with age(with r values of 0.381,0.339,0.349,respectively,all P<0.001),while FF values of subscapular muscle were weakly correlated with age(r=0.216,P=0.017).The FF values of supraspinatus,infraspinatus,subscapularis were moderately correlated with the duration of symptoms(with r values of 0.442,0.412,0.314,respectively,all P<0.001),while FF values of teres minor were weakly correlated with symptom duration(r=0.277,P=0.002).The degree of injury of the supraspinatus tendon was significantly correlated with the FF value of the supraspinatus muscle(r_(s)=0.740,P<0.001),was strongly correlated with the FF value of the infraspinatus muscle(r_(s)=0.596,P<0.001),and was weakly correlated with the FF values of the subscapularis muscle and the teres minor muscle(with rs value of 0.257,0.212,P=0.004,0.019).There was a positive correlation between the degree of supraspinatus injury grade and Goutallier grade and Thomazeau grade(with rs value of 0.757,0.737,all P<0.001).The FF value of supraspinatus muscle was significantly different in Goutallier grade and Thomazeau grade(all P<0.001).Conclusions:3.0 T MR IDEAL-IQ sequence could objectively assessed the degree of rotator cuff injury,and the quantified FF was positively correlated with supraspinatus injury grade,and associated with age and duration of symptoms.