磁共振成像技术定量检测铁过载的临床意义

Significance of magnetic resonance imaging in the detection of iron overload

目的 研究磁共振成像（MRI）技术定量检测铁过载的情况并与传统方法进行比较.方法 选取2010年12月至2012年12月北京4家医院临床上怀疑有铁过载而在北京协和医院进行MRI定量检测的患者53例,应用MRI T2＊ mapping的方法测定患者肝脏及心脏T2＊值,依照MRI T2＊值判断铁过载情况并与同期检测的血清铁蛋白（SF）、输血量及其他临床表现及实验室指标进行比较分析.结果 本组男37例,女16例,中位年龄50岁（15 ～ 72岁）,其中,骨髓增生异常综合征（MDS）25例,再生障碍性贫血（AA）16例,骨髓纤维化5例,血色病2例,β地中海贫血携带者2例,体检发现SF升高3例.45例患者有输血史;SF＞ 1000 μg/L者49例;有铁过载相关体征者10例;肝功能异常38例,血糖升高者32例.经MRI定量检测,10例无肝脏及心脏铁过载;43例出现肝脏铁过载,其中14例为轻度铁过载,22例为中度铁过载,7例为重度铁过载.43例肝脏铁过载患者中2例合并心脏铁过载,分别为MDS和慢性AA患者,有大量输血史,其中l例合并心力衰竭表现.肝脏T2＊值与SF、输血量之间均无相关性（P=0.050、0.820）;肝脏T2＊值和心脏T2＊值之间也无相关性（P =0.129）.结论 MRI定量检测脏器铁过载的方法是现有血清测定铁含量的有益补充,与目前评估铁过载的手段相结合,可以更全面地了解患者铁过载的程度.

Objective To evaluate the significance of magnetic resonance imaging （MRI） T2＊ value analysis in patients with iron overload and compare it with other clinical parameters.Methods A total of 53 patients with suspected iron overload were recruited from four Beijing hospitals from December 2010 to December 2012.Their liver and heart T2 ＊ values were calculated and their serum ferritin （SF）,transferin saturation,blood transfusion volume and other clinical parameters were recorded and analyzed.Results There were 37 males and 16 females with a medium age of 50 years（15-72 years）.Their etiologies included myelodysplastic syndromes （MDS,n =25）,aplastic anemia （AA,n =16）,myelofibrosis （n =5）,hemachromatosis （n =2） and β thalassaemia （n =2）,and 3 patients with high SF values were found on regular health examinations.Among them,there were transfusion history （n =45）,SF ＞ 1000 μg/L （n =49）,sign of iron overload （n =10）,abnormal liver function （n =38） and hyperglycemia （n =32）.T2＊ value analysis showed that 10 patients had no evidence of iron overload,43 patients had liver iron overload （14 mild,22 moderate and 7 severe） and 2 patients had heart iron overload （1 MDS with heavy transfusion history and 1 AA with heart failure）.No relations existed between T2 ＊ value and SF （P =0.050）,T2 ＊ value and transfusion volume （P =0.820）,and liver T2 ＊ value and heart T2 ＊ value （P =0.129）.Conclusions MRI T2＊ value is an accurate way of quantitative detection of iron overload.It provides a comprehensive understanding of patients with iron overload in conjunctions with MRI T2 ＊ value and other clinical parameters.