2型糖尿病患者器官脂肪沉积的磁共振定量研究

摘要

目的 脂毒性在糖尿病及其相关并发症的发展进程中起到至关重要的作用,然而器官脂肪定量的“金标准”为活检及组织化学染色,其均为有创操作并有其自限性,故本研究应用MR 3点式T2*校正Dixon技术进行体内器官脂肪沉积的无创性定量,并比较糖尿病患者和正常志愿者腹部器官脂肪沉积的差异.资料与方法 本研究共招募65例临床诊断为2型糖尿病患者和34例正常受试者.每位受试者均接受3.0 T MR腹部轴位常规平扫及T2*校正的3点式Dixon序列扫描.比较两组受试者的肝脏、脾脏和胰腺的脂肪分数,分析受试者各器官脂肪沉积与体重指数、年龄等的相关性.结果 2型糖尿病组的肝脏和脾脏脂肪分数分别为(5.4±4.3)％、(3.7±14)％,明显高于正常组[(2.9±1.3)％、(3.0±0.9)％],差异有统计学意义(P＜0.05).2型糖尿病组的胰腺脂肪分数与正常组差异无统计学意义(P＞0.05).99例受试者的肝脏、脾脏和胰腺的脂肪分数与BMI相关(r=0.379、0.305、0.306,P＜0.05),仅胰腺脂肪分数与年龄存在相关性(r=0.261,P＜0.05).结论 无创性MR T2*校正的3点式Dixon技术能够发现糖尿病患者的肝脏及脾脏的异常脂肪沉积,有助于腹部器官脂质沉积的评估.%Purpose Lipotoxicity plays an important role in the progression of diabetes and its complications,and the gold standards for organs' lipid quantification are biopsy or histochemical staining,which are invasive and have their own limitations.Thus,our research was to identify the difference in organ lipid deposition between type 2 diabetic patients and healthy volunteers by using noninvasive three-point T2* corrected Dixon imaging.Materials and Methods Sixty-five type 2 diabetic patients and 34 healthy volunteers were included in this study.All participants underwent three-echo Dixon with 3.0T MR imager.Dixon imaging parameters [hepatic fat fraction (HFF),splenic fat fraction (SFF),pancreatic fat fraction (PFF)] were collected.All of the MRI parameters were compared.The relationship between HFF,SFF,PFF and BMI,age were analyzed.Results The hepatic and splenic lipid percentage in diabetic group [HFF=(5.4±4.3)％;SFF=(3.7± 1.4)％] was significantly higher than healthy volunteers group [HFF=(2.9± 1.3)％;SFF=(3.0± 0.9)％;P＜0.05,respectively].However,there was no significant difference in pancreatic fat fraction between diabetic and healthy groups (P＞0.05).There were positive correlations between HFF,SFF,PFF and BMI (r=0.379,0.305 and 0.306,P＜0.05).Moreover,only the positive correlation between pancreatic fat fraction and age were observed (r=0.261,P＜0.05).Conclusion The three-point T2* corrected Dixon revealed the abnormalities of hepar and spleen lipid accumulation in diabetic patients.Thus,the three-point Dixon imaging may potentially aid in evaluating the lipid deposition of abdominal organs.