Susan Francis1, Charlotte E Buchanan, Ben Prestwich, Maarten W Taal. 1. aSir Peter Mansfield Imaging Centre, School of Physics and Astronomy bCentre for Kidney Research and Innovation, Division of Medical Sciences and Graduate Entry Medicine, University of Nottingham, Nottingham, United Kingdom.
Abstract
PURPOSE OF REVIEW: This review focuses on the recent technological advances in quantitative sodium (Na) MRI to provide a noninvasive measure of tissue viability for use in clinical studies of patients with kidney disease. Na MRI is the only noninvasive imaging technique that allows for the absolute spatial quantification of tissue sodium concentration (TSC), providing assessment of the corticomedullary sodium gradient (CMSG) in the kidney, and allowing measures of TSC in the skin and muscle. RECENT FINDINGS: Na MRI of the kidney has demonstrated the sensitivity to measure the CMSG, providing the normal range in healthy individuals and demonstrating a reduction in CMSG in kidney disease and transplanted kidneys. Studies using Na and H MRI have shown that in humans, skeletal muscle and skin can store sodium without water retention, and that sodium concentrations in muscle and skin increase with advancing age. Recent studies have shown that TSC can be mobilised during haemodialysis, and that skin sodium content links closely to left ventricular mass in patients with chronic kidney disease. SUMMARY: Na MRI is currently a research technique, but with future advances, Na MRI has potential to become a noninvasive renal biomarker and a measure of tissue sodium storage for clinical studies.
PURPOSE OF REVIEW: This review focuses on the recent technological advances in quantitative sodium (Na) MRI to provide a noninvasive measure of tissue viability for use in clinical studies of patients with kidney disease. Na MRI is the only noninvasive imaging technique that allows for the absolute spatial quantification of tissue sodium concentration (TSC), providing assessment of the corticomedullary sodium gradient (CMSG) in the kidney, and allowing measures of TSC in the skin and muscle. RECENT FINDINGS: Na MRI of the kidney has demonstrated the sensitivity to measure the CMSG, providing the normal range in healthy individuals and demonstrating a reduction in CMSG in kidney disease and transplanted kidneys. Studies using Na and H MRI have shown that in humans, skeletal muscle and skin can store sodium without water retention, and that sodium concentrations in muscle and skin increase with advancing age. Recent studies have shown that TSC can be mobilised during haemodialysis, and that skin sodium content links closely to left ventricular mass in patients with chronic kidney disease. SUMMARY: Na MRI is currently a research technique, but with future advances, Na MRI has potential to become a noninvasive renal biomarker and a measure of tissue sodium storage for clinical studies.
Authors: Nicholas M Selby; Peter J Blankestijn; Peter Boor; Christian Combe; Kai-Uwe Eckardt; Eli Eikefjord; Nuria Garcia-Fernandez; Xavier Golay; Isky Gordon; Nicolas Grenier; Paul D Hockings; Jens D Jensen; Jaap A Joles; Philip A Kalra; Bernhard K Krämer; Patrick B Mark; Iosif A Mendichovszky; Olivera Nikolic; Aghogho Odudu; Albert C M Ong; Alberto Ortiz; Menno Pruijm; Giuseppe Remuzzi; Jarle Rørvik; Sophie de Seigneux; Roslyn J Simms; Janka Slatinska; Paul Summers; Maarten W Taal; Harriet C Thoeny; Jean-Paul Vallée; Marcos Wolf; Anna Caroli; Steven Sourbron Journal: Nephrol Dial Transplant Date: 2018-09-01 Impact factor: 5.992