The table is adapted from Table 1 in Selby et al (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6106645/), distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/). Adaptations include changes in the text of various entries and a new column "RENAL" with recommendations for use by EIBALL

 

RENAL

MRI technique

Description of MRI technique

Pathophysiological process informed by MRI biomarker

Biomarker measured

Units of measurement

 

Volumetry1-4!

measured from T1- and/or T2-weighted structural images

Key measure in patients with ADPKD but may also be important in CKD

TKV
Height-adjusted TKV
Cortical volume
Total cyst volume in ADPKD

mL
mL/m
mL
mL

 

Diffusion weighted imaging (DWI)5,6!

True diffusion (D), pseudo-diffusion (tubular/vascular flow, D*) and flowing fraction (F)

Changes in renal micro- structure, oedema, or changes in renal perfusion and in water handling in the tubular compartment.

ADC
True diffusion (D)
Pseudo-diffusion (D*)
Flowing fraction (F)

mm2/s
mm2/s
mm2/s
%

 

DCE MRI (MR renograophy)7!

Gadolinium-based contrast agents to change the T1 relaxation time of water in tissues. Allows measurement of perfusion and GFR.

Perfusion and filtration per unit tissue, vascularity and tubular transit times. Gd not recommended where renal function compromised.

Single kidney GFR
Tissue blood flow
Tubular flow
Filtration fraction
Tubular transit time
Tubular volume fraction

mL/min
mL/min/100mL
mL/min/100mL
%
min
%

Recommended for clinical trials

T1 mapping8,9!

Provides a quantitative map over the whole kidney for T1 values. T1 is a tissue-specific time variable that can distinguish different tissues.

Changes in the molecular environment, for example, water content, viscosity, temperature, fibrosis, interstitial oedema, cellular swelling.

T1
(whole kidney, cortex, medulla, cortico- medullary difference)

ms

 

T2 mapping9,10!

As with T1 mapping, provides quantification of T2 as a tissue-specific time parameter. Changes with tissue water content.

Changes in the molecular environment but assumed to be more sensitive to the effects of oedema and/ or inflammation. Limited experience in human kidney disease to date.

T2
(whole kidney, cortex, medulla, cortico- medullary difference)

ms

 

Diffusion-tensor imaging (DTI)5,7!

Assesses directionality of diffusion [fractional anisotropy (FA)] and allows assessment of the degree of organization in space of oriented tissues

Changes in the microstructure that lead to a change in the preferred direction of water diffusion, for instance, tubular dilatation, tubular obstruction or a loss in the organization of medullary tubules.

FA
 


MD (mean diffusivity)

Scale value between 0 and 1, where 0 = isotropic diffusion (equal in all directions) and 1 = complete anisotropy (diffusion in a single axis) mm2/s

           
 

BOLD MRI11,12!

Indirect assessment of oxygenation. Deoxygenated haemoglobin shortens the transverse relaxation time constant (T2*).

Changes in renal oxygenation or changes in the microstructure of the capillary bed.

T2*
R2* (1/ T2*)

ms
s-1

 

ASL13-17!

Magnetically labelled water protons in blood that act as a endogenous tracer. Labelled images are subtracted from control images to generate perfusion maps.

Cortical perfusion

Tissue blood flow

mL/min/100g

Not recommended for clinical trials

Phase contrast MRI18,19!

Measures blood flow in renal arteries: ‘phase shift’ is proportional to its proton velocity, allowing calculation of flow.

Resistance to flow due to downstream obstruction, or changes in systemic haemodynamics.

Renal artery blood flow (flux)
Renal artery velocity
Renal artery area

mL/s

cm/s
cm2

 

Magnetization transfer (MT)20!

the fraction of large macromolecules or immobilized cell membranes in tissue.

shown to correlate with fibrosis in the kidney

MT ratio

%

 

Elastography, hyperpolarization, and 23-sodium MRI.21-23!

 

Technique dependent

Technique dependent

Technique dependent

  1. Bae KT, Commean PK, Lee J. Volumetric measurement of renal cysts and parenchyma using MRI: phantoms and patients with polycystic kidney dis- ease. J Comput Assist Tomogr 2000; 24: 614–619
  2. Bae K, Park B, Sun H et al. Segmentation of individual renal cysts from MR images in patients with autosomal dominant polycystic kidney disease. Clin J Am Soc Nephrol 2013; 8: 1089–1097
  3. Brosnahan GM. Volume progression in polycystic kidney disease. N Engl J Med 2006; 355: 733
  4. Irazabal MV, Rangel LJ, Bergstralh EJ et al. Imaging classification of autoso- mal dominant polycystic kidney disease: a simple model for selecting patients for clinical trials. J Am Soc Nephrol 2015; 26: 160–172
  5. Caroli A, Schneider M, Friedli I et al. Diffusion-weighted magnetic resonance imaging to assess diffuse renal pathology: a systematic review and statement paper. Nephrol Dial Transplant 2018; 33 (Suppl 2): ii29–ii40
  6. Le Bihan D, Breton E, Lallemand D et al. Separation of diffusion and perfusion in intravoxel incoherent motion MR imaging. Radiology 1988; 168: 497–505
  7. Notohamiprodjo M, Reiser MF, Sourbron SP. Diffusion and perfusion of the kidney. Eur J Radiol 2010; 76: 337–347
  8. Friedli I, Crowe LA, Berchtold L et al. New magnetic resonance imaging in- dex for renal fibrosis assessment: a comparison between diffusion-weighted imaging and T1 mapping with histological validation. Sci Rep 2016; 6: 30088
  9. Wolf M, de Boer A, Sharma K et al. Magnetic resonance imaging T1- and T2-mapping to assess renal structure and function: a systematic review and statement paper. Nephrol Dial Transplant 2018; 33 (Suppl 2): ii41–ii50
  10. de Bazelaire CM, Duhamel GD, Rofsky NM et al. MR imaging relaxation times of abdominal and pelvic tissues measured in vivo at 3.0 T: preliminary results. Radiology 2004; 230: 652–659
  11. Pruijm M, Mendichovszky IA, Liss P et al. Renal blood oxygenation level- dependent magnetic resonance imaging to measure renal tissue oxygena- tion: a statement paper and systematic review. Nephrol Dial Transplant 2018; 33 (Suppl 2): ii22–ii28
  12. Pruijm M, Milani B, Burnier M. Blood oxygenation level-dependent MRI to assess renal oxygenation in renal diseases: progresses and challenges. Front Physiol 2017; 7: 667
  13. Niles DJ, Artz NS, Djamali A et al. Longitudinal assessment of renal perfu- sion and oxygenation in transplant donor-recipient pairs using arterial spin labeling and blood oxygen level-dependent magnetic resonance imaging. Invest Radiol 2016; 51: 113–120
  14. Gardener AG, Francis ST. Multislice perfusion of the kidneys using parallel imaging: image acquisition and analysis strategies. Magn Reson Med 2010; 63: 1627–1636
  15. Ritt M, Janka R, Schneider MP et al. Measurement of kidney perfusion by magnetic resonance imaging: comparison of MRI with arterial spin labeling to para-aminohippuric acid plasma clearance in male subjects with meta- bolic syndrome. Nephrol Dial Transplant 2010; 25: 1126–1133
  16. Tan H, Koktzoglou I, Prasad PV. Renal perfusion imaging with two- dimensional navigator gated arterial spin labeling. Magn Reson Med 2014; 71: 570–579
  17. Odudu A, Nery F, Harteveld AA et al. Arterial spin labelling MRI to measure renal perfusion: a systematic review and statement paper. Nephrol Dial Transplant 2018; 33 (Suppl 2): ii15-ii21
  18. Dambreville S, Chapman AB, Torres VE et al. Renal arterial blood flow measurement by breath-held MRI: accuracy in phantom scans and reproducibility in healthy subjects. Magn Reson Med 2010; 63: 940–950
  19. Villa G, Ringgaard S, Hermann I et al. Phase-contrast magnetic resonance imaging to assess renal perfusion: a systematic review and statement paper. MAGMA 2019
  20. Adler J, Swanson SD, Schmiedlin-Ren P et al. Magnetization transfer helps detect intestinal fibrosis in an animal model of Crohn disease. Radiology 2011; 259: 127–135
  21. Francis S, Buchanan CE, Prestwich B et al. Sodium MRI:a new frontier in imaging in nephrology. Curr Opin Nephrol Hypertens 2017; 26: 435–441 Schroeder M, Laustsen C. Imaging oxygen metabolism with hyperpolarized magnetic
  22. 31. resonance: a novel approach for the examination of cardiac and renal function. Biosci Rep 2017; 37: BSR20160186
  23. Leung G, Kirkpalani A, Szeto SG et al. Could MRI Be Used To Image Kidney Fibrosis? A Review of Recent Advances and Remaining Barriers. Clin J Am Soc Nephrol 2017; 6: 1019-1028