Renal Ultrasound in Chronic Kidney Disease
Renal ultrasound measurements have been suggested to predict outcome in chronic kidney disease. In the past, research interest focuses on intrarenal resistance indices, which are calculated from maximal systolic (V max sys) and maximal end-diastolic flow velocity (V max enddiast) in intrarenal (interlobar) arteries.
Resistive Index (RI) = (V max sys - V max enddiast) / V max sys
Figure 1: Resistive index in a healthy subject (representative example)
Cohort studies suggest that high resistance indices predict worse renal and overall survival in CKD patients and in renal allograft recipients, presumably as intrarenal damage results in increased resistance indices.
Nonetheless, high resistance indices may not only indicate local renal damage, but may alternatively reflect systemic (atherosclerotic) vessel disease. We initiated a cohort study which recruited 140 CKD patients, in whom renal resistance indices correlated with common carotid intima media thickness (IMT), which is an established marker of subclinical atherosclerosis.
Figure 2: Correlation between intima media thickness of common carotid arteries and resistance indices in patients suffering from CKD
Thus, in a prospective study of 105 allograft recipients, intrarenal resistance indices were shown to be worse predictors of survival with functioning allograft than carotid intima media thickness measurements.
Figure 3: Survival with functioning allograft in renal transplant patients stratified by carotid intima media thickness (right figure) and by intrarenal resistance indices (left figure).
We hypothesize that measurements of renal resistance indices can be corrected for systemic atherosclerotic burden. We are presently testing whether specifity of transplant renal resistance indices might be increased by comparing allograft resistance indices to indices measured in arteries of other organs, such as splenic arteries.
Publications
Selection of publications concerning the research focus since 2004
Lennartz CS, Pickering JW, Seiler-Mussler S, Bauer L, Untersteller K, Emrich IE, Zawada AM, Radermacher J, Tangri N, Fliser D, Heine GH.
External Validation of the Kidney Failure Risk Equation and Re-Calibration with Addition of Ultrasound Parameters.
Clin J Am Soc Nephrol. 2016. Impact factor: 4.6 Abstract
Grün OS, Herath E, Weihrauch A, Flügge F, Rogacev KS, Fliser D, Heine GH.
Does the Measurement of the Difference of Resistive Indexes in Spleen and Kidney Allow a Selective Assessment of Chronic Kidney Injury?
Radiology 2012 Sep;264(3):894-902. Impact factor: 5.7 Abstract
Seiler S, Colbus SM, Lucisano G, Rogacev KS, Gerhart MK, Ziegler M, Fliser D, Heine GH.
Ultrasound renal resistive index is not an organ-specific predictor of allograft outcome.
Nephrol Dial Transplant 2012 Jan 30. Impact factor: 3.6 Abstract
Gerhart MK, Seiler S, Grün OS, Rogacev KS, Fliser D, Heine GH.
Indices of systemic atherosclerosis are superior to ultrasound resistance indices for prediction of allograft survival.
Nephrol Dial Transplant 2010 Apr;25(4):1294-300. Impact factor: 3.3. Abstract
Heine GH, Reichart B, Ulrich C, Köhler H, Girndt M.
Do Ultrasound Renal Resistance Indices Reflect Systemic Rather Than Renal Vascular Damage in Chronic Kidney Disease?
Nephrology Dialysis Transplantation 2007, 22, 163-170. Impact factor: 3.2. Abstract
Heine GH, Gerhart MK, Ulrich C, Köhler H, Girndt M.
Renal Doppler resistance indices are associated with systemic atherosclerosis in kidney transplant recipients.
Kidney Int 2005 68: 878-885. Impact factor: 4.8. Abstract
