Comparing the difference of measured GFR of ectopic pelvic kidney between anterior and posterior imaging processing in renal dynamic imaging

Abstract

Objective To compare and analyze the difference of measured glomerular filtration rate (GFR) of ectopic pelvic kidney between anterior and posterior imaging processing in renal dynamic imaging.Methods There were 10 patients collected retrospectively,with ectopic kidneys in pelvic cavity confirmed by ultrasound,CT,renal dynamic imaging and other imaging modalities.All images of ectopic kidneys in renal dynamic imaging were processed by anterior and posterior methods respectively.The ectopic kidney was only processed in anterior imaging,ectopic kidney and contralateral normal kidney were processed in posterior imaging.Total GFR equalled the sum of GFR of normal kidney in posterior imaging and GFR of ectopic kidney in anterior imaging,was compared with total GFR of two kidneys in posterior imaging and GFR in two-sample method.All correlation analysis were completed between GFRs from three methods and all patients were followed up.Statistically paired t-test and bivariate correlation analysis test were used.Results The mean GFR of ectopic kidney in anterior imaging equal to (27.48±12.24) ml/(min· 1.73 m2).It was more than GFR [(10.71 ±4.74) ml/ (min· 1.73 m2)] in posterior imaging above 46％ (t=5.481,P＜0.01).There was no significant difference (t=-2.238,P＞0.05),but better correlation (r=0.704,P＜0.05)between total GFR in anterior imaging and GFR in two-sample method.There was significant difference (t=4.629,P＜0.01)and worse correlation(r=0.576,P＞0.05)between total GFR in posterior imaging and GFR in two-sample method.Conclusion Comparing with GFR in posterior imaging,GFR in anterior imaging can more truly reflect function condition of ectopic pelvic kidney in renal dynamic imaging. Key words: Glomerular filtration rate ; Ectopic kidney ; Renal dynamic imaging