Spiral Perfusion Imaging with Consecutive Echoes (SPICE™) for the Simultaneous Mapping of DSC- and DCE-MRI Parameters in Brain Tumor Patients: Theory and Initial Feasibility

Abstract

Dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) are the perfusion imaging techniques most frequently used to probe the angiogenic character of brain neoplasms. With these methods, T1- and T2/T2*-weighted imaging sequences are used to image the distribution of gadolinium (Gd)-based contrast agents. However, it is well known that Gd exhibits combined T1, T2, and T2* shortening effects in tissue, and therefore, the results of both DCE- and DSC-MRI can be confounded by these opposing effects. In particular, residual susceptibility effects compete with T1 shortening, which can confound DCE-MRI parameters, whereas dipolar T1 and T2 leakage and residual susceptibility effects can confound DSC-MRI parameters. We introduce here a novel perfusion imaging acquisition and postprocessing method termed Spiral Perfusion Imaging with Consecutive Echoes (SPICE) that can be used to simultaneously acquire DCE- and DSC-MRI data, which requires only a single dose of the Gd contrast agent, does not require the collection of a precontrast T1 map for DCE-MRI processing, and eliminates the confounding contrast agent effects due to contrast extravasation. A detailed mathematical description of SPICE is provided here along with a demonstration of its utility in patients with high-grade glioma.

Imaging vascular and hemodynamic features of the brain using dynamic susceptibility contrast and dynamic contrast enhanced MRI

“…Given the importance of MR angiography (MRA) and venography in many applications (such as stroke), the development of novel multi-echo sequences with strategic parameter selection could enable the simultaneous derivation of both MRA and perfusion-based vascular parameters (Chen et al, 2018b(Chen et al, , 2018aYe et al, 2013). Recent developments in k-space sampling strategies include the use of non-Cartesian sampling strategies, such as spiral (Paulson et al, 2016b;Schmainda et al, 2015a) and radial (Jonathan et al, 2013;Rossi Espagnet et al, 2015) trajectories, to circumvent the known image distortion and signal artifacts associated with EPI trajectories. Additionally, the ability to combine acceleration strategies (such as parallel imaging, partial Fourier techniques, compressed sensing, and view-sharing) has the potential to significantly improve the spatial and/or temporal resolution.…”

“…The main drawbacks to EPI-based acquisitions are signal dropout (particularly around sinuses and, in the case of tumors, around resection cavities) and image distortion. More advanced readout options have been developed to overcome these drawbacks; these options include advanced EPI readouts (Gelderen et al, 2000a;Newbould et al, 2007a), single-line acquisitions (Quarles et al, 2012a), and non-Cartesian readouts such as spiral or radial acquisitions (Jonathan et al, 2013;Paulson et al, 2016a). While generally less available clinically, these advanced methods can provide significant advantages over traditional DSC-MRI methods with single-shot EPI.…”

“…While the low temporal resolution may preclude its use in brain tumor studies, other neuropathologies with less stringent temporal kinetics may benefit from the whole-brain coverage of this approach. Another promising example is the Spiral Perfusion Imaging with Consecutive Echoes (SPICE) method that was used to simultaneously acquire DSC-and DCE-MRI data (Paulson et al, 2016b). Using this approach, two echoes with tunable T 1 and T 2 * -weightings, corresponding to short and long TEs, respectively, were acquired with high temporal resolution ( Figure 3).…”

“…This T 1 -weighted signal can be used for DCE-MRI analysis, particularly in multi-echo DSC studies (Paulson et al, 2016b;Schmiedeskamp et al, 2013Schmiedeskamp et al, , 2012Skinner et al, 2014;Stokes et al, 2014;Vonken et al, 1999b). For DCE-MRI studies with multiple echoes, removal of T 2 * effects (due to intravascular CA compartmentalization) using Eq.…”

Multisite Concordance of DSC-MRI Analysis for Brain Tumors: Results of a National Cancer Institute Quantitative Imaging Network Collaborative Project

“…Several studies report a lower SNR [35] as well as greater inaccuracy when gamma-variate fitting is used for brain tumor DSC-MRI data especially in the presence of contrast agent leakage [19, 20]. Though gamma-variate fitting suppresses the post-bolus baseline making it appear that leakage has been corrected there is no physiologic basis for this correction and it does not appropriately consider leakage that can occur during the bolus [36]. Gamma-variate fitting was not used by any of the SW platforms evaluated in the present study.…”