The contrast-enhanced ultrasound imaging characteristics of renal cortical blood perfusion and the relationship of those with glomerular filtration rate in elderly patients with moderate-to-severe renal artery stenosis / 中华老年医学杂志

ABSTRACT

Objective To investigate the renal cortical perfusion parameters assessed by contrast-enhanced ultrasound(CEUS)in elderly patients with moderate-to severe renal artery stenosis (RAS),and relationship of those with glomerular filtration rate(GFR).Methods A total of 59 elderly patients with unilateral moderate to severe RAS(50％-99％)admitted into Beijing Hospital during June 2017 to December 2018 were consecutively enrolled in the cross sectional and self-control study.Based on the GFR assessed by radionuclide renal dynamic imaging,patients were divided into the mild-(35＞GFR≥25 ml/min,n=18),moderate-(25 ＞ GFR≥ 15 ml/min,n =37) and severe renal dysfunction(GFR＜ 15 ml · min-1,n =4) groups.CEUS evaluated-renal cortical perfusion parameters,including area under curve (AUC),ascending slope (A),derived peak intensity (DPI),time to peak (TTP) and mean transit time(MTT),were compared among different levels of severity of renal dysfunction groups.Pearson correlation analysis was used to evaluate the relationship between CEUS imaging-evaluated renal cortical perfusion parameters and radionuclide renal dynamic imaging-assessed GFR.Results Compared with the mild renal dysfunction group,the moderate renal dysfunction group showed a reduced AUC and A(P＜0.05),and the severe renal dysfunction group showed more markedly reduced AUC,A,DPI,TTP and MTT (P ＜ 0.05).Compared with the moderate renal dysfunction group,the severe renal dysfunction group showed a reduced AUC,A and GFR(P ＜0.05),while no significant differences in TTP and MTT were found.As far as relationship between renal cortical perfusion parameters and GFR were concerned,Pearson correlation analysis demonstrated that AUC(r =0.804),A(r =0.813) and DPI(r =0.733) were significantly and positively correlated with GFR(all P ＜ 0.05).However,renal function (r =-0.721),TTP(r =-0.744) and MTT(r =-0.743)were negatively correlated with GFR(P＜0.05).And the degree of renal artery stenosis was poorly correlated with GFR (r =-0.462).Conclusions For elderly patients with unilateral moderate to severe RAS,contrast-enhanced ultrasonography can display the changes of renal cortical blood perfusion parameters along with the aggravation of renal function impairment.AUC and A are strongly positively correlated with GFR.The degree of renal artery stenosis is poorly correlated with renal function.And more studies are needed to confirm these findings.