MRI同反相位成像、表观扩散系数以及弥散加权成像序列在椎体良恶性疾病鉴别中的价值

目的：探讨MRI的同反相位成像（ IP／OP）、表观扩散系数（ ADC）以及弥散加权成像（ DWI）序列在鉴别椎体良恶性疾病中的应用价值。方法选择恶性肿瘤椎体压缩骨折患者80例作为恶性组，良性疾病导致的椎体压缩性骨折80例作为良性组，均行MRI常规序列及DWI扫描，并采用双回波技术在3D快速扰相梯度回波序列中采集IP／OP图像；分析良恶性病变病例的DWI信号特点，定量测定两组椎体的ADC值、信号强度比（SIR）值和信号衰减程度（SAR）值。结果良性及恶性组病灶DWI序列均可表现为高、等、低或混杂信号，两组DWI信号改变情况比较，差异无统计学意义（P＞0．05）；良性组ADC值为（2．24±0．31）×10－3 mm2／s，高于恶性组ADC值的（1．72±0．36）×10－3 mm2／s（P＜0．05）；良性组SIR值为0．58±0．15，高于的恶性组的1．26±0．16（P＜0．05），良性组SAR值为0．45±0．36，低于恶性组的0．15±0．07（P＜0．05）。结论 DWI信号不能准确鉴别椎体良恶性病变，而ADC值和SIR值、SAR值具有重要的鉴别诊断价值。

Value of MRI in-phase and opposed-phase,apparent diffusion coefficient and diffusion-weighted imaging in distinguishing benign and malignant spinal lesions

Objective To explore the application value of MRI in-phase and opposed-phase(IP/OP),apparent diffusion coefficient (ADC) and diffusion-weighted imaging(DWI) in distinguishing benign and malignant spinal lesions .Methods A total of 80 patients with vertebral compression fractures caused by malignant tumor were enrolled as malignant group , and 80 patients with vertebral compression fractures caused by benign disease as benign group .The patients in both groups received MRI scanning with routine sequence and DWI . And the double-echo technology was used to obtain IP/OP imaging by three-dimensional fast spoiled gradient-echo.The characteristics of DWI signals were analyzed in the cases of benign and malignant lesions .The ADC,signal intensity ratio ( SIR) and signal attenuation ratio (SAR) were quantitatively determined.Results High,equal,low or mixed signals of DWI sequences were observed in both of benign group and malignant group.No significant difference in the signal change of DWI was observed between two groups (P>0.05).The ADC in the benign group was (2.24 ±0.31) ×10 -3 mm2/s,and was higher than that in the malignant group (1.72 ±0.36) ×10 -3 mm2/s (P<0.05).The SIR in the benign group was 0.58 ±0.15,and was higher than that in the malignant group (1.26 ±0.16)(P<0.05). The SAR in the benign group was 0.45 ±0.36,and was lower than that in the malignant group (0.15 ±0.07)(P<0.05).Conclusion DWI signal can not be used to distinguish benign and malignant spinal lesions of vertebral bodies accurately .But ADC,SIR and SAR are valuable in the differential diagnosis of benign and malignant lesions .