Ryszard Stefan Gomolka1, Alexander Ciritsis2, Andreas Meier2, Cristina Rossi2. 1. Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistr. 100, 8091, Zürich, Switzerland. ryszard.gomolka@usz.ch. 2. Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistr. 100, 8091, Zürich, Switzerland.
Abstract
INTRODUCTION: Although relevant for assessment of sodium in multiple endocrine pathways, 23Na-T1 quantification is challenging due to technical limitations (SAR, B1 inhomogeneity) or influence of tissue's local molecular dynamics. Hereby, we propose T1 quantification of 23Na-MRI signal acquired over the abdomen using a centric-reordered saturation-recovery (SR) true fast imaging with steady state precession (TrueFISP) sequence. MATERIALS AND METHODS: Measurements were performed at 3T using a dual-tunable 23Na/1H coil in 7 healthy volunteers (TR/TE = 858-928/1.57 ms; flip angle = 90°; bandwidth = 450 Hz/px; voxel size = 5 × 5 × 10 mm3). Variable T1-weighting was achieved applying non-selective saturation pre-pulses delayed from the centre of the k-space acquisition by 25, 40, 60, 120 and 250 ms. T1-curve fitting was performed slice-wise, separately for average intensity values from the manually segmented areas of the renal parenchyma and spinal canal, over the increasing SR times- assuming monoexponential signal pattern. RESULTS: Mean ± standard deviation of 23Na-T1 was found as 29 ± 10 ms and 35 ± 8 ms for the renal parenchyma and the spinal canal, respectively. DISCUSSION: 23Na-T1 quantification using a SR-TrueFISP is feasible in clinical settings, in the images constrained by clinically applicable acquisition time of reduced spatial resolution or averages.
INTRODUCTION: Although relevant for assessment of sodium in multiple endocrine pathways, 23Na-T1 quantification is challenging due to technical limitations (SAR, B1 inhomogeneity) or influence of tissue's local molecular dynamics. Hereby, we propose T1 quantification of 23Na-MRI signal acquired over the abdomen using a centric-reordered saturation-recovery (SR) true fast imaging with steady state precession (TrueFISP) sequence. MATERIALS AND METHODS: Measurements were performed at 3T using a dual-tunable 23Na/1H coil in 7 healthy volunteers (TR/TE = 858-928/1.57 ms; flip angle = 90°; bandwidth = 450 Hz/px; voxel size = 5 × 5 × 10 mm3). Variable T1-weighting was achieved applying non-selective saturation pre-pulses delayed from the centre of the k-space acquisition by 25, 40, 60, 120 and 250 ms. T1-curve fitting was performed slice-wise, separately for average intensity values from the manually segmented areas of the renal parenchyma and spinal canal, over the increasing SR times- assuming monoexponential signal pattern. RESULTS: Mean ± standard deviation of 23Na-T1 was found as 29 ± 10 ms and 35 ± 8 ms for the renal parenchyma and the spinal canal, respectively. DISCUSSION: 23Na-T1 quantification using a SR-TrueFISP is feasible in clinical settings, in the images constrained by clinically applicable acquisition time of reduced spatial resolution or averages.
Entities:
Keywords:
23Na; 3D SR-TrueFISP; Clinical MRI; Sodium T1
Authors: James T Grist; Frank Riemer; Esben S S Hansen; Rasmus S Tougaard; Mary A McLean; Joshua Kaggie; Nikolaj Bøgh; Martin J Graves; Ferdia A Gallagher; Christoffer Laustsen Journal: Kidney Int Date: 2020-06-22 Impact factor: 10.612