Robust pCASL Perfusion Imaging using a 3D Cartesian Acquisition with Spiral Profile Reordering (CASPR)

Abstract

Purpose:

To improve the robustness of ASL measured perfusion using a novel Cartesian Acquisition with Spiral Profile Reordering (CASPR) 3D TSE in the brain and kidneys.

Methods:

The CASPR view ordering followed a pseudo-spiral trajectory on a Cartesian grid, by sampling the center of k-space at the beginning of each echo train of a segmented 3D TSE acquisition. With IRB approval and written informed consent, 14 normal subjects (9 brain and 5 kidneys) were scanned with pCASL perfusion imaging using 3D CASPR and compared against 3D linear TSE (brain and kidneys), the established 2D EPI and 3D GRASE perfusion (brain), and 2D SShTSE perfusion (kidneys). The signal to noise ratio (SNR) and the quantitative perfusion values were compared among different acquisitions.

Results:

3D CASPR TSE achieved robust perfusion across all slices compared to 3D linear TSE in the brain and kidneys. Compared to 2D EPI, 3D CASPR TSE showed higher SNR across the brain (p<0.01), and exhibited good agreement (36.4±4.7 and 36.9±5.3 mL/100g/min with 2D EPI and 3D CASPR respectively), and with 3D GRASE (27.9±7.2 mL/100g/min). Compared to a single slice 2D SShTSE acquisition, 3D CASPR TSE achieved robust perfusion across the entire kidneys in similar scan time with comparable quantified perfusion values (154.1±74.6 and 151.7±70.6 mL/100g/min with 2D SShTSE and 3D CASPR respectively).

Conclusion:

The CASPR view ordering with 3D TSE achieves robust ASL perfusion in the brain and kidneys due to the sampling of the center of k-space at the beginning of each echo train.