Readout-segmented echo-planar imaging in the evaluation of sinonasal lesions: A comprehensive comparison of image quality in single-shot echo-planar imaging.

ABSTRACT

PURPOSE: To investigate the role of readout-segmented echo-planar imaging using parallel imaging and a two-dimensional (2D) navigator (RESOLVE) in the evaluation of sinonasal lesions and to qualitatively and quantitatively compare the image qualities of single-shot echo-planar imaging (SS-EPI) and RESOLVE. MATERIALS AND METHODS: Both sinonasal SS-EPI and RESOLVE images were acquired from 32 patients on a 3-T MR scanner. Image quality, lesion conspicuity and the distortions of the SS-EPI and RESOLVE images were qualitatively evaluated by two radiologists. Distortion was also quantitatively evaluated by comparing the distances between the same anatomic points on TSE-T1WI, TSE-T2WI, SS-EPI and RESOLVE images. The apparent diffusion coefficient (ADC) values, signal-to-noise ratios (SNRs), and contrast-to-noise ratios (CNRs) of the two DWIs were compared. RESULTS: The comparisons of the qualitative scores indicated that RESOLVE significantly improved the image quality and lesion conspicuity and reduced the distortion of the sinonasal diseases. The orbit, skull base, temporal bone and upper neck were also better displayed on RESOLVE. Quantitative evaluations revealed that RESOLVE greatly reduced but did not completely remove the distortion. The ADC values of the sinonasal lesions on RESOLVE were lower than those on SS-EPI, whereas no differences were found in the brainstem. The SNR of RESOLVE was lower than that of SS-EPI. There were no differences in the CNRs of the two diffusion-weighted imaging (DWI) techniques. CONCLUSION: RESOLVE significantly improved the image quality for evaluations of sinonasal lesions by reducing the susceptibility artifacts, distortion and blurring compared with SS-EPI. RESOVLE offers more accurate ADC values of sinonasal lesions than SS-EPI.