Abstract

PurposeTo achieve 3D T(2)w imaging of the prostate with 1-mm isotropic resolution in less than 3 min. MethodsWe devised and implemented a 3D T-2-prepared multishot balanced steady state free precession (T(2)prep-bSSFP) acquisition sequence with a variable density undersampled trajectory combined with a total variation regularized iterative SENSE (TV-SENSE) reconstruction. Prospectively undersampled images of the prostate (acceleration factor R = 3) were acquired in 11 healthy subjects in an institutional review board-approved study. Image quality metrics (subjective signal-to-noise ratio, contrast, sharpness, and overall prostate image quality) were evaluated by 2 radiologists. Scores of the proposed accelerated sequence were compared using the Wilcoxon signed-rank and Kruskal-Wallis non-parametric tests to prostate images acquired using a fully sampled 3D T(2)prep-bSSFP acquisition, and with clinical standard 2D and 3D turbo spin echo (TSE) T(2)w acquisitions. A P-value 0.05 was considered significant. ResultsThe 3x accelerated 3D T(2)prep-bSSFP images required a scan time (min:s) of 2:45, while the fully sampled 3D T(2)prep-bSSFP and clinical standard 3D TSE images were acquired in 8:23 and 7:29, respectively. Image quality scores (contrast, sharpness, and overall prostate image quality) of the accelerated 3D T(2)prep-bSSFP, fully sampled T(2)prep-bSSFP, and clinical standard 3D TSE acquisitions along all 3 spatial dimensions were not significantly different (P > 0.05). Conclusion3D T(2)w images of the prostate with 1-mm isotropic resolution can be acquired in less than 3 min, with image quality that is comparable to a clinical standard 3D TSE sequence but only takes a third of the acquisition time.