title: Brain Default Mode Network Changes after Renal Transplantation: A Diffusion-Tensor Imaging and Resting-State Functional MR Imaging Study.
abstract: OBJECTIVE
  To investigate structural and functional alterations of the default mode network (DMN) in the brain after renal transplantation in patients with end-stage renal disease by using diffusion-tensor imaging and resting-state functional MR imaging.
  
  
  METHODS
  This prospective study was approved by the local medical research ethics committee, and written informed consent was obtained. Twenty-one patients with end-stage renal disease (15 men, six women; mean age ± standard deviation, 32 years ± 9.5) who were scheduled to undergo renal transplantation and 21 healthy control subjects (15 men, six women; mean age, 31 years ± 6.5) were included. Diffusion-tensor imaging and resting-state functional MR imaging were performed in all subjects. Patients were imaged both before and 1 month after renal transplantation. Structural (mean diffusivity, fractional anisotropy, path length, and number of tracts derived from diffusion-tensor imaging tractography) and functional (temporal correlation coefficient derived from resting-state functional MR imaging) connectivity of the DMN were quantitatively compared with two-sample t tests or paired t tests. Intergroup correlation analysis was performed to compare structural or functional indexes and results of neuropsychological or blood biochemistry tests.
  
  
  RESULTS
  Mean diffusivity was decreased in the fiber bundles connecting the posterior cingulate cortex and the precuneus to the bilateral inferior parietal lobules in patients after renal transplantation compared with that in patients before transplantation (P < .05). Temporal correlation coefficients for patients after renal transplantation nearly reached the levels of those for control subjects (all, P > .05). The change in mean diffusivity of the fiber bundles connecting the posterior cingulate cortex and the precuneus to the right inferior parietal lobule positively correlated with the change in hematocrit levels (r = 0.522, P = .015), the change in temporal correlation coefficients between the posterior cingulate cortex or precuneus and left or right inferior parietal lobules correlated with changes in number connection test type A scores (r = -0.549, P = .010) and digit symbol test scores (r = 0.533, P = .013).
  
  
  CONCLUSIONS
  Functional connectivity changes in the DMN, which were associated with improved hematocrit levels and cognitive function, may recover earlier than structural connectivity changes do 1 month after renal transplantation.
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Long Jiang
authors.initials: LJ
authors.lastname: Zhang
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Jiqiu
authors.initials: J
authors.lastname: Wen
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Xue
authors.initials: X
authors.lastname: Liang
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Qi
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: U Joseph
authors.initials: UJ
authors.lastname: Schoepf
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Julian L
authors.initials: JL
authors.lastname: Wichmann
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Cole M
authors.initials: CM
authors.lastname: Milliken
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Hui Juan
authors.initials: HJ
authors.lastname: Chen
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Xiang
authors.initials: X
authors.lastname: Kong
authors.affiliation: From the Department of Medical Imaging (L.J.Z., X.L., R.Q., H.J.C., X.K., G.M.L.) and National Clinical Research Center of Kidney Disease (J.W.), Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; and Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (U.J.S., J.L.W., C.M.M.).
authors.forename: Guang Ming
authors.initials: GM
authors.lastname: Lu
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000601:surgery*; D007677:Kidney Function Tests; D016030:Kidney Transplantation; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009483:Neuropsychological Tests