弥散加权成像和波谱分析在肝豆状核变性诊断及随访中的应用价值

Role of Diffusion Weighted Magnetic Resonance Imaging and Spectroscopy in the Diagnosis and Follow-up of Hepatolenticular Degeneration

目的通过弥散加权成像(DWI)及磁共振波谱成像(MRS)分析肝豆状核变性(HLD)脑部不同代谢物的变化,探讨DWI处于不同信号时,病变区域表现扩散系数(ADC)值、MRS与病理变化的关系及治疗后疗效判定。方法对临床确诊并纳入研究标准的53例HLD患者,按DWI信号高低分为DWI高信号组(n=31)和DWI低信号组(n=22),分别于治疗前及治疗后4个月行磁共振常规扫描、DWI和波谱分析,比较ADC值,N-乙酰天门冬氨酸(NAA)/肌酸(Cr)、胆碱复合物(Cho)/Cr比值及治疗后变化。结果治疗前DWI高信号组NAA/Cr显著高于低信号组(P=0.002),而ADC值、Cho/Cr显著低于低信号组(P=0.004,P=0.014);治疗后DWI高信号组NAA/Cr明显高于低信号组(P=0.036),而ADC值、Cho/Cr与低信号组比较差异无统计学意义(P>0.05)。DWI高信号组治疗后ADC值及NAA/Cr显著高于治疗前(P=0.006,P=0.008),Cho/Cr与治疗前差异无统计学意义(P>0.05)。DWI低信号组治疗后NAA/Cr显著高于治疗前(P=0.015),ADC值、Cho/Cr与治疗前比较差异无统计学意义(P>0.05)。结论 DWI成像联合MRS应用可以在一定程度上评价HLD铜沉积过程中的微观结构和代谢变化,弥补常规磁共振成像检查对代谢观察的不足,对其早期诊断及疗效评估具有重要价值。

Objective To explore the changes of different brain metabolites during hepatolenticular degeneration using diffusion weighted magnetic resonance imaging （DWI） and magnetic resonance spectroscopy （MRS） in patients with hepatolenticular degeneration and study the correlation of apparent diffusion coefficient （ADC） values and MRS with the different pathological changes. Methods Totally 53 patients with hepatolen- titular degeneration were enrolled in this study and divided into DWI high-signal group （ n = 31 ） and DWI low- signal group （n = 22）. Magnetic resonance scan, DWI, and spectroscopy were performed before treatment and 4 months after treatment. The changes of ADC value, N-acetyl aspartate （NAA） /creatine （Cr） ratio, and choline （Cho） /Cr ratio were recorded. Results- Before treatment, the NAA/Cr ratio was significantly higher in the DWI high-signal group than in DWI low-signal group （ P = 0. 002 ）, whereas ADC value and NAA/Cr ra- tio were significantly lower （P = 0.004, P = 0. 014, respectively）. After treatment, the NAA/Cr ratio was still significantly higher in the DWI high-signal group （ P = 0.036 ） , while the differences of ADC value and Cho/Cr ratio showed no statistical deference （P 〉 0.05 ）. In the DWI high-signal group, the ADC value and NAA/Cr ratio were significantly elevated after treatment （ P = 0.006, P = 0. 008 ） , whereas the Cho/Cr ratio showed no significant change （ P 〉 0.05 ）. In the DWI low signal group, NAA/Cr ratio was significantly in- creased after treatment （ P = 0. 015 ） , while the ADC value and Cho/Cr ratio showed no significant change （P 〉 0.05）. Conclusions DWI combined MRS imaging can be used to evaluate the microscopic structure and metabolic changes during copper deposition and thus, compared with the conventional magnetic resonance imaging provide more information on metabolism. Therefore, they can be useful tools in the early diagnosis and efficacy evaluation of hepatolenticular degeneration.