钆喷酸葡胺对肾功能轻度异常者齿状核T1信号的影响

Effect of gadopentetate dimeglumine on T1 signal intensity in dentate nucleus from patients with mild renal dysfunction

目的探讨钆喷酸葡胺对肾功能轻度异常者磁共振(MR)平扫齿状核T1高信号的影响。方法回顾性分析59例华中科技大学同济医学院附属同济医院进行3次或3次以上MR增强扫描病例的临床及影像资料,测量右侧小脑齿状核及右侧额叶白质平均信号强度。以右侧额叶白质的信号强度作为基数,计算小脑齿状核的信号强度比。采用配对t检验比较首末两次MR检查小脑齿状核与额叶白质的信号比值(I0,I1);采用独立t检验分析肾功能与首末次小脑齿状核-额叶白质信号比值差值(ΔI)的关系;采用Spearman检验分析ΔI与MR增强检查次数、末次增强检查和末次平扫检查的时间间隔的相关性。采用多重线性回归分析方法分析ΔI与年龄、性别、末次增强检查和末次平扫检查的时间间隔及增强检查次数的关系。结果在肾功能正常组,I0为0.89±0.10,I1为0.95±0.11;肾功能轻度异常组中,I0为0.84±0.10,I1为0.95±0.12。两组I1均高于I0(P<0.01)。肾功能正常组ΔI为0.06±0.05,肾功能轻度异常组ΔI为0.10±0.08,后者大于前者(P<0.05)。在所有患者中,ΔI与MR增强扫描次数存在正相关(r=0.794,P<0.05)。进一步的多重线性回归分析显示,MR增强扫描的次数与ΔI有统计学差异,而年龄、性别、时间间隔与ΔI无明显统计学差异。结论在多次使用钆喷酸葡胺(Gd-DTPA)进行MR增强扫描后,即使肾功能轻度异常者[60 mL min^-1 (1.73 m^2)-1≤eGFR<90 mL min^-1 (1.73 m^2)^-1],也会出现颅内小脑齿状核T1WI信号增高,且显著高于肾功能正常者。在临床工作中,对于肾功能轻度异常患者,应尽量避免使用钆喷酸葡胺等线状含钆对比剂。

Objective To investigate the effect of gadopentetate dimeglumine on the T1 high signal intensity of magnetic resonance images in the dentate nucleus in patients with mild renal abnormalities.Methods Retrospective analysis was performed on 59 cases of clinical and imaging data from three or more MR enhanced scans in our hospital,measuring the average signal intensity of right dentate nucleus and right frontal white matter.The signal intensity ratio of the dentate nucleus was calculated by using the signal intensity of the right frontal white matter as the baseline.The dentate nucleus-frontal white matter signal ratios(I0,I1)in the first and the last two magnetic resonance examinations were compared using paired t test;independent t test was used to analyze the relationship between renal function and dentate nucleus-frontal white matter signal ratio(ΔI);Spearman test was used to analyze the correlation between the signal intensity ratio difference and the number of magnetic resonance enhancement examinations,and between the signal intensity difference and time interval between the last enhanced MR scan and the last non-enhanced scan.Multiple linear regression analysis was used to analyze the relationship between signal intensity ratio difference and age,gender,number of enhancements and time interval between the last enhanced MR scan and the last plain-scan scan.Results In the normal renal function group,I0 was 0.892±0.098,I1 was 0.951±0.106;in the mild renal dysfunction group,I0 was 0.845±0.101,and I1 was 0.949±0.121.I1 in both groups was higher than I0(P<0.01).TheΔI in the normal renal function group was 0.059±0.048,and that in the mild renal dysfunction group was 0.103±0.078.The latter was larger than the former(P<0.05).In all patients,there was a positive correlation betweenΔI and the number of MR enhancement scans(r=0.794,P<0.05).Further multiple linear regression analysis showed that the number of MR enhanced scans was statistically different from the first and last signal differenceΔI,the difference between the first and last signal valuesΔI and age or gender showed no difference of statistical significance.Conclusions After repeated MR-enhanced scanning with gadopentetate dimeglumine(Gd-DTPA),even if the renal function is mildly abnormal[60 mL min-1 (1.73 m 2)-1≤eGFR<90 mL min^-1 (1.73 m^2)^-1],the dentate nucleus showed an increased signal on T1WI,which was significantly higher than those with normal renal function.In clinical practice,linear GBCA such as gadopentetate dimeglumine should be avoided as far as possible in patients with mild renal dysfunction..