Inside Cover Image

Abstract

The cover image is based on the Research Article Magnetic resonance elastography‐derived stiffness of the kidneys and its correlation with water perfusion by Deep Gandhi et al., https://doi.org/10.1002/nbm.4237.

Magnetic resonance elastography resolving all gross anatomical segments of the kidney during controlled hydration

“…To our knowledge this is the first study to investigate hydration related biomechanical alterations in all-well segmented-gross anatomical renal segments simultaneously. This is in contrast to many previous studies which used either point-like or simple polygonshaped ROIs, sometimes defined on single slices only (Rouvière et al, 2011;Dittmann et al, 2017;Brown et al, 2020;Han et al, 2020;Dillman et al, 2022;Güven et al, 2022), or combined different renal structures within segments (Bensamoun et al, 2011;Lee et al, 2012;Streitberger et al, 2014;Low et al, 2015;Marticorena Garcia et al, 2016;Kirpalani et al, 2017;Kline et al, 2018;Gandhi et al, 2019;Lang et al, 2019;Gandhi et al, 2020;Han et al, 2020;Marticorena Garcia et al, 2021;Shatil et al, 2022;Chen et al, 2023b;Elsingergy et al, 2023). Only Marticorena Garcia et al [in two studies (Marticorena Garcia et al, 2018b;Marticorena Garcia et al, 2019)], and Chen et al (2023a) used comparably well segmented renal structures.…”

“…ii) To our knowledge, this is the first study to use a rotating eccentric mass to induce acoustic waves into the kidney (Runge et al, 2018;Manduca et al, 2021). So far, only pneumatic (Bensamoun et al, 2011;Rouvière et al, 2011;Lee et al, 2012;Low et al, 2015;Marticorena Garcia et al, 2016;Dittmann et al, 2017;Kirpalani et al, 2017;Marticorena Garcia et al, 2018a;Marticorena Garcia et al, 2018b;Kline et al, 2018;Gandhi et al, 2019;Lang et al, 2019;Marticorena Garcia et al, 2019;Brown et al, 2020;Gandhi et al, 2020;Han et al, 2020;Kennedy et al, 2020;Marticorena Garcia et al, 2021;Zhang et al, 2021;Dillman et al, 2022;Güven et al, 2022;Shatil et al, 2022;Chen et al, 2023a;Chen et al, 2023b;Elsingergy et al, 2023), or piezoelectric drivers (Streitberger et al, 2014) were used. Only one study reported the total shear displacement from 8-35 μm at 45 and 76 Hz (pneumatic system) (Rouvière et al, 2011).…”

“…Since then, MRE methods have been improved and have shed light on the potential to assess (patho-) physiological renal processes (Morrell et al, 2017). According to a Pubmed search, 20 October 2023, we could identify 26 studies on the human kidney (excluding animal, ex-vivo and tumor studies) (Bensamoun et al, 2011;Rouvière et al, 2011;Lee et al, 2012;Streitberger et al, 2014;Low et al, 2015;Marticorena Garcia et al, 2016;Dittmann et al, 2017;Kirpalani et al, 2017;Marticorena Garcia et al, 2018a;Marticorena Garcia et al, 2018b;Kline et al, 2018;Gandhi et al, 2019;Lang et al, 2019;Marticorena Garcia et al, 2019;Brown et al, 2020;Gandhi et al, 2020;Han et al, 2020;Kennedy et al, 2020;Marticorena Garcia et al, 2021;Zhang et al, 2021;Dillman et al, 2022;Güven et al, 2022;Shatil et al, 2022;Chen et al, 2023a;Chen et al, 2023b;Elsingergy et al, 2023). So far, only pneumatic (Bensamoun et al, 2011;Rouvière et al, 2011;Lee et al, 2012;Low et al, 2015;Marticorena Garcia et al, 2016;Dittmann et al, 2017;Kirpalani et al, 2017;Marticorena Garcia et al, 2018a;Marticorena Garcia et al, 2018b;Kline et al, 2018;Gandhi et al, 2019;…”

“…So far, only pneumatic (Bensamoun et al, 2011;Rouvière et al, 2011;Lee et al, 2012;Low et al, 2015;Marticorena Garcia et al, 2016;Dittmann et al, 2017;Kirpalani et al, 2017;Marticorena Garcia et al, 2018a;Marticorena Garcia et al, 2018b;Kline et al, 2018;Gandhi et al, 2019;Lang et al, 2019;Marticorena Garcia et al, 2019;Brown et al, 2020;Gandhi et al, 2020;Han et al, 2020;Kennedy et al, 2020;Marticorena Garcia et al, 2021;Zhang et al, 2021;Dillman et al, 2022;Güven et al, 2022;Shatil et al, 2022;Chen et al, 2023a;Chen et al, 2023b;Elsingergy et al, 2023), or piezoelectric drivers (Streitberger et al, 2014) were used. From those, 18 studies included healthy subjects, i.e., native kidneys (Bensamoun et al, 2011;Rouvière et al, 2011;Streitberger et al, 2014;Low et al, 2015;Marticorena Garcia et al, 2016;Dittmann et al, 2017;Marticorena Garcia et al, 2018b;Kline et al, 2018;Gandhi et al, 2019;Lang et al, 2019;Marticorena Garcia et al, 2019;Brown et al, 2020;Gandhi et al, 2020;Han et al, 2020;…”

“…However, we found no biomechanical differences between the cortex and medulla during either fasting or hydration. Regardless of the hydration state, four studies showed that the medulla was stiffer than the cortex (Bensamoun et al, 2011;Rouvière et al, 2011;Streitberger et al, 2014;Gandhi et al, 2019), and four studies found that the medulla was less stiff than the cortex (Dittmann et al, 2017;Marticorena Garcia et al, 2018b;Gandhi et al, 2020;Dillman et al, 2022). These contradictory findings can be explained by the lack of well-defined segmentations, resolution, and the application of different methods.…”