MR水、脂分离Dixon方法及弥散成像对椎体骨折性质的鉴别研究

The differential study of vertebral fracture with MRI water-fat separation dixon technique and diffusion imaging

目的探讨磁共振脂肪抑制Dixon技术水、脂分离及弥散成像在椎体骨折性质的诊断和鉴别诊断中的应用价值。方法收集病理及临床随访证实的椎体良性压缩性骨折22例25个椎体,包括骨质疏松性压缩性骨折15例,外伤性骨折7例;恶性压缩性骨折20例35个椎体,包括转移瘤19例,骨髓瘤1例。对所有患者行MRI常规矢状位T1WI、T2WI、横断位T2WI序列;T2WI Dixon、DWI、DTI序列扫描。结果良性压缩性骨折组脂肪信号分数平均值为(0.25±0.01),恶性压缩性骨折组脂肪信号分数平均值为(0.09±0.04),组间差异均有统计学意义(P<0.01)。良性压缩性骨折组与恶性压缩性骨折组ADC值间差异有统计学意义(P<0.01)。良性压缩性骨折组与恶性压缩性骨折组FA值差异无统计学意义(P>0.05)。对FF值及ADC值绘制良、恶性ROC曲线,得出良恶性椎体压缩性骨折诊断的临界值分别为0.136、1.409×10-3 mm2/s。结论磁共振FF值及ADC值参数结合有助于椎体骨折性质的诊断和鉴别诊断。

Objective To explore the value of MRI water-fat separation fat suppression Dixon technique and diffusion imaging in differential diagnosis of vertebral fracture. Methods 22 cases of vertebral benign compression fracture and 25 vertebral body fractures （15 patients with osteoporotic compression fractures, 7 cases of traumatic fractures） were included in the study. There were 20 cases of malignant compression fractures in 35 vertebral bodies （19 cases of metastatic tumor, 1 case of multiple myeloma）. MR sequence included conventional sagittal T1WI, axial T2WI, Dixon water-fat separation T2WI, DWI, DTI. Results There was statistic significant difference （ P 〈0.01） between fat signal score of the group of benign vertebral compression fracture （0.25 ±0.01） and the group of malignant vertebral compression fractures （0.09±0.04）. The ADC value of benign compression fracture and malignant compression fractures was statistically significant difference were existed between the two groups （ P 〈0.01）. The FA value of benign compression Fracture group was （0.32±0.08）. The FA value of malignant compression fractures group was （0.29±0.44）. There was no statistical significant difference between the two groups （ P 〉0.05）. Through drawing ROC curve used the FF value and ADC value of benign and malignant, the diagnostic critical value of benign and malignant vertebral compression fracture was 0. 136 and 1. 409 × 10^-3 mm2/s. Conclusion The combination of fat signal score and ADC value is helpful for clinical differential diagnosis of vertebral fracture.