| Objective:To evaluate the value of BOLD and ASL MRI in the early longitudinal evaluation of renal allografts dysfunction in terms of blood oxygen distribution and perfusion.Subjects and methods:A total of 44 cases of kidney transplantation recipients who underwent renal transplantation from December 2014 to June 2018 were enrolled in this study.All subjects were examined by conventional MR,oblique sagittal BOLD and ASL MR with 3.0 T MR scanner?Siemens,Magnetom Trio Tim,Germany?.Serum creatinine?SCr?levels were recorded in all kidney transplantation recipients within 3 months after renal transplantation,evaluated glomerular filtration rate?eGFR?was calculated using a simplified dietary modification of diet in renal disease?MDRD?formula.The patients were divided into three groups according to the eGFR calculated from SCr values within 2 weeks and 2 weeks to 3 months after surgery:?1?:group 1:renal allografts function continued well group(within 2 weeks and 2weeks to 3 months after surgery eGFR all?60 mlˇmin-1ˇ1.73 m-2,n=16);?2?group2:renal allografts function short-term impaired group(within 2 weeks after surgery eGFR all?60 mlˇmin-1ˇ1.73 m-2and the eGFR decreased to<60 mlˇmin-1ˇ1.73 m-2from 2 weeks to 3 months after surgery,n=14);?3?group 3:renal allografts function damage sustained group(within 2 weeks and 2 weeks to 3 months after surgery eGFR all<60 mlˇmin-1ˇ1.73 m-2,n=14).BOLD and ASL MRI were performed in 44 patients at 2 weeks and 3 months after operation,Record the eGFR value on the day of inspection.Cortex R2*value,medulla R2*value and renal cortex blood flow?RBF?value were measured and calculated in each group.An intra-class correlation coefficient?ICC?was used to evaluate the consistency of the results between two doctors.A chi square test was used to compare the difference in sex distribution between renal transplant recipients in 3 groups,One-way analysis of variance?ANOVA?and Bonferroni method was used to compare the differences of age,the first time after surgery mean arterial pressure,warm ischemia time,first time eGFR,cortex R2*,medulla R2*,cortex RBF values and follow-up eGFR values among 3 group of kidney transplantation recipients.Binary logistic regression analysis and receiver operating characteristic curve?ROC?were used to analyze the first BOLD and ASL indices after operation and the efficacy of the combined application of BOLD and ASL in differentiating renal allografts function continued well group from renal allografts function short-term impaired group.The differences of eGFR,BOLD and ASL were compared between the two groups by paired sample t test.Pearson correlation analysis was used to evaluate the correlation between BOLD,ASL and eGFR indices in the first and follow-up kidney transplantation recipients,and the correlation between BOLD and ASL indices in the first and follow-up kidney transplantation recipients.P<0.05 was statistically significant.Results:?1?The consistency of kidney transplantation recipients BOLD and ASL value of between the two doctors was good,ICC was all above 0.75.?2?There were significant differences in warm ischemic time among the groups?P<0.01?.There were no significant differences in gender,age and first mean arterial pressure?P>0.05?.?3?There were significant differences in the first time eGFR between group3 and group 1 and group 2?P<0.01?,and no significant differences between group 1and group 2?P>0.05?;There were significant differences in follow-up eGFR values between group 1 and group 2 and group 3?P<0.01?,and no significant differences between group 2 and group 3?P>0.05?.?4?There were significant differences in R2*values of renal cortex between group 3 and group 1 and group 2?P<0.05?,and no significant differences between group 1 and group 2?P>0.05?;There were significant differences in R2*values of renal medulla and RBF values of renal cortex between groups?P<0.05?.?5?The values of R2*and RBF in the renal cortex of kidney transplantation recipients had higher diagnostic ability in the renal allograft function continued well group and renal allograft function short-term impaired group,and there was no significant difference between the two indices?P>0.05?.?6?The sensitivity and specificity of BOLD combined with ASL were 92.9%and 100%respectively,and the AUC of BOLD combined with ASL was 0.991 in the renal allograft function continued well group and renal allograft function short-term impaired group,it was significantly higher than BOLD?AUC 0.783,sensitivity and specificity 62.5%and 92.9%respectively?and ASL?AUC 0.819,sensitivity and specificity 68.8%and 100%respectively??P<0.05?.?7?During the follow-up,the eGFR value and cortex R2*value of the transplanted kidney remained stable in the renal allograft function continued well group,the medulla R2*value and cortex RBF value of the transplanted kidney increased slightly?P<0.01?;During the follow-up,the cortex R2*value of the transplanted kidney remained stable in the renal allograft function short-term impaired group,eGFR value,medulla R2*value and cortex RBF value of the transplanted kidney decreased significantly?P<0.01?;During the follow-up,the eGFR value and cortex R2*value of the transplanted kidney were slightly higher in the renal function damage sustained group?P<0.05?,the medulla R2*value and cortex RBF value of the transplanted kidney were significantly higher?P<0.01?.?8?The first time and follow-up examinations showed significant correlation with eGFR,and the correlation was statistically significant?P<0.05?.The first and follow-up examinations showed significant correlation between R2*and RBF except for the R2*values of renal cortex and RBF values of renal cortex follow-up examinations.The correlation was statistically significant?P<0.05?.Conclusion:BOLD and ASL MRI can longitudinal monitor the blood oxygen distribution and blood perfusion of renal allografts function,and detect renal allografts dysfunction in early stage.The combination of BOLD and ASL has high differential diagnostic value. |
PDF Full Text Request