Compartmentalised reconstruction of cardiac 31P concentric ring MRSI at 7T

Motivation: Cardiac 31P MRS allows the probing of metabolism in various heart diseases, however, commonly employed 3D MRSI techniques are slow even at 7 T. Goal(s): Our work aims to evaluate the use of compartment-based localised spectroscopy using a linear algebraic model (SLAM). Approach: 31P MRSI data was collected using concentric ring trajectory acquisitions and SLAM was used to reconstruct 31P signal from the myocardium. Results: We show increased SNR and reduced uncertainty in determining the cardiac PCr signal, in addition to also reducing the repeatability of PCr/ATP ratio measurements when compared to a 2.5 minute, NUFFT-reconstructed CRT protocol. Impact: Repeatable and high-SNR 31P acquisitions will allow the probing of cardiac energetics in patient populations that were previously unable to attend prolonged scan sessions at ultra-high field strengths.