非铁磁性口腔金属材料磁共振成像伪影的实验研究  

Experimental research on magnetic resonance imaging artifacts caused by non-ferromagnetic dental metallic materials

作　　者：韩武[1] 潘小波[2] 郝楠[2] 彭利辉[2] 钟爱喜[2] 刘光雪[2] 

机构地区：[1]广西壮族自治区人民医院放射科,南宁市530021 [2]广西壮族自治区人民医院口腔修复科,南宁市530021

出　　处：《广西医学》2015年第7期888-890,899,共4页Guangxi Medical Journal

基　　金：广西科学研究与技术开发计划(桂科攻0719006-2-20)

摘　　要：目的比较8种不同非铁磁性口腔金属材料在3种磁共振成像序列中产生的伪影面积,为临床选择适宜磁共振成像检查的金属修复材料和成像序列提供实验依据。方法选用口腔科临床常用的8种铸造金属材料[银汞合金、银钯合金、金钯合金、3种金合金(金含量:89.5%、55.6%、15.0%)、钛合金和纯钛]及树脂材料(对照组)制作立方体模型,置于充满蒸馏水的圆筒状塑料容器中,采用磁共振成像FSE-T1WI、FSE-T2WI、GRE-T2WI序列进行检查,测量各种材料在3种序列中产生的伪影面积。结果不同金属材料和不同扫描序列均对扫描时的伪影面积有影响。在FSE-T1WI序列中,银汞合金、银钯合金、金钯合金、金合金的伪影面积与对照组的伪影面积比较无差异(P>0.05);在FSE-T2WI序列和GRE-T2WI序列中,银钯合金、金钯合金、钛合金、纯钛的伪影面积均大于对照组(P<0.05)。纯钛、钛合金在3种序列下的伪影面积均大于对照树脂组(P<0.01)。结论贵金属合金的MR成像质量受到投照序列和合金组成成分的影响,与金含量也有一定关系;纯钛和钛合金在不同投照序列下,均能引起MRI伪影;FSE-T2WI和GRE-T2WI序列对各个金属的伪影面积的影响要大于FSE-T1WI序列。Objective To evaluate the artifact sizes of eight kinds of non -ferromagnetic dental metallic materials in three magnetic resonance imaging （ MRI ） sequences in order to provide experimental basis for choosing the optimum metallic materials and imaging sequences for MRI in clinical practice.Methods Cubical samples of eight kinds of dental metallic materials（amalgams,Ag-Pd alloy, Au-Pd alloy,three gold alloys（Au8：9 .5%,55.6%,150.%）,titanium alloy and pure titanium） were fabricated and placed in a cylindrical plastic vessel filled with distilled water .Acrylic resin was used as control.All samples were imaged by means of MRI apparatus with three sequences,T1-weighted fast spin-echo（FSE-T1WI）,T2-weighted fast spin-echo（FSE-T2WI） and T2-weighted gradient-echo（GRE-T2WI）. MRI artifact sizes of different metal materials and three sequences were measured.Results Artifact size showed significant differences among different metal materials and different sequences.The artifact size of amalgams,Ag-Pd alloy,Au-Pd alloy or gold alloy was not significantly different from that of control group in FSE-T1WI sequence（P〉0.05）,while the artifact sizes of Ag-Pd alloy,Au-Pd alloy,titanium alloy and pure titanium were significantly larger in FSE-T2WI and GRE-T2WI sequence compared with the controls（P〈0.05）.Pure titanium and titanium alloy showed significantly larger artifact sizes in the three sequences compared with the controls（P〈0.01）.Conclusion MR image quality of precious metal alloys is affected by the sequence used and the alloy compositions,and also has relations with the gold content.Pure titanium and its alloys pose a problem with respect to causing MRI artifacts in different sequences.FSE-T2 WI and GRE-T2 WI sequence have more effects on the MRI artifact sizes of different alloys compared with FSE-T1 WI sequence.

关 键 词：磁共振成像 金属伪影 口腔铸造合金 非铁磁性 

分 类 号：R445.2[医药卫生—影像医学与核医学]