合成磁共振序列在轻度膝骨性关节炎磁共振扫描图像质量评价及弛豫定量中的应用

Application of synthetic MRI in evaluation of image quality and quantitative relaxometry in MRI scans of mild knee osteoarthritis

摘要:

目的 探讨合成磁共振（MAGiC）序列在轻度膝骨性关节炎（KOA）磁共振扫描图像质量评价及弛豫定量中的应用。方法 选取2023年3月—2024年3月在中南大学湘雅医院就诊的20例轻度KOA患者及20例健康志愿者，共80只膝关节。磁共振图像扫描序列包括常规序列T₁WI、T₂WI、PDWI、PDWI-FS及MAGiC序列。MAGIC序列图像导入后处理软件获得分解后的T₁WI、T₂WI、PDWI、PDWI-STIR图像及T₁、T₂、PD弛豫定量图谱。比较常规序列和MAGiC分解序列的图像质量及两组图像的软骨损伤检出率，同时在MAGiC序列弛豫定量图上测量对照组及轻度KOA组软骨的T₁值、T₂值、PD值。结果 常规序列组与MAGiC序列分解组T₁WI、T₂WI、PDWI图像质量比较，差异均无统计学意义（P > 0.05）；常规序列组PDWI-FS图像质量优于MAGiC序列分解组PDWI-STIR（P <0.05）。常规序列组与MAGiC序列分解组轻度KOA患者软骨损伤检出率比较，差异无统计学意义（P >0.05）。轻度KOA组T₁值、T₂值和PD值均高于对照组（P <0.05）。结论 MAGiC序列分解结构图可有效检出轻度KOA患者的软骨损伤，其多参数弛豫定量可对KOA软骨损伤程度进行量化，对于早期KOA患者的诊断和病程进展监测具有较高的临床应用价值。

Abstract:

Objective To explore the application value of the synthetic magnetic resonance imaging (MRI) method termed MAGnetic resonance image Compilation (MAGiC) in evaluation of image quality and quantitative relaxometry in MRI scans of mild knee osteoarthritis (KOA).Methods A total of 80 knee MRI images were collected from 20 normal volunteers and 20 patients with mild KOA in our hospital from March 2023 to March 2024. The MRI scanning sequences included conventional sequences T₁WI, T₂WI, PDWI, PDWI-FS, and MAGiC sequences. The MAGiC images were imported into post-processing software to obtain decomposed T₁WI, T₂WI, PDWI, and PDWI-STIR images, and T₂, T₁, and PD quantitative maps. The image quality of conventional sequences and MAGiC decomposed sequences and the detection rate of cartilage injury in the two groups of images were compared. Meanwhile, the T₁, T₂, and PD values of the cartilage in the normal control group and the mild KOA group were measured on the quantitative maps of the MAGiC sequences.Results The image quality of conventional sequences T₁WI, T₂WI, PDWI, and fat-suppressed PDWI (PDWI-FS and PDWI-STIR) was higher than that of MAGiC decomposed sequences (P < 0.05). There was no difference in the detection rate of cartilage injury in mild KOA patients between the conventional sequences and the MAGiC decomposed sequences (P> 0.05). The T₁, T₂, and PD relaxation time of the normal control group were higher than those in the mild KOA group (P < 0.05).Conclusions The images decomposed from MAGiC sequences can effectively detect cartilage injury in patients with mild KOA, and the multiparameter quantification of relaxation helps to quantify the degree of cartilage injury among these patients. Thus, MAGiC is of high clinical application value for diagnosis and monitoring disease progression of early-stage KOA.