High-resolution 3D T2-weighted SPACE sequence with compressed sensing for the prostate gland: diagnostic performance in comparison with conventional T2-weighted images.

Abstract

To compare the diagnostic performance of high-resolution 3D T2-weighted imaging (T2WI) with compressed sensing (CS) sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) to that of conventional T2WI with turbo spin echo (TSE) in prostate MRI. This study evaluated 179 patients (mean age 69.1 ± 9.3) who underwent prostate biopsy after prostate prebiopsy MRI, including two sets of three-plane T2WI with TSE (thickness: 3mm, scan time: 10min 4s) and CS SPACE (thickness: 0.6mm, scan time: 4min 55s). Two radiologists evaluated two sets of images with the Prostate Imaging-Reporting and Data System (PIRADS) classification and determined the extraprostatic extension (EPE) of the lesion. The diagnostic performance to detect prostate cancer (PIRADS classification) and EPE was compared between the two T2WI sets. Clinically significant cancer (CSC) was diagnosed in 103 patients (57.5%). Areas under the receiver operating characteristic curve of the PIRADS classification on both image sets with T2 TSE and T2 CS SPACE were higher than 0.7 and did not show significant differences for either radiologist (p > 0.05). EPE was confirmed in 25 of 70 patients underwent prostatectomy. For evaluating EPE on MRI, the sensitivity and specificity did not differ between the two T2WI sequences (p > 0.05). High-resolution 3D T2WI using CS SPACE, which was acquired within a shorter acquisition time than three-plane T2 TSE, showed comparable diagnostic performance to conventional T2 TSE for detecting CSC and evaluating EPE.