Clinical Study of Rs-EPI DWI to Improve Imaging Quality and Assessment on Intracranial Mass Lesions

Objective To explore the clinical value of readout-segmented echo planar imaging (Rs-EPI) sequence in the assessment of intracranial mass lesions compared to the standard single-shot EPI (Ss-EPI) sequence. Methods We included 21 patients with intracranial mass lesions who underwent both Ss-EPI diffusion weighted imaging（DWI）and Rs-EPI DWI at 3.0T MR scanner with a twenty-channel head-neck coil. The quality of images was assessed by two experienced radiologists independently. The differences in image quality between two sequences were analyzed using Wilcoxon signed-rank test. Inter-observer agreements were analyzed using interclass correlation coefficient （ICC） and Kappa test. Results All objectives were completed on 3.0T MR. The signal-to-noise ratio（SNR） and contrast-to-noise ratio （CNR） in Rs-EPI DWI were higher than those in Ss-EPI DWI (130.46±49.10 vs. 71.58±30.43，P=0.000; 33.22±18.86 vs. 17.92±18.72，P=0.003). The scores of overall image quality, ghost artifact where next to the paranasal sinuses，mastoid air cells and frontal sinus of Rs-EPI DWI were significantly higher than those of Ss-EPI DWI. Meanwhile, the geometric distortion of anatomical structures of Rs-EPI DWI were significantly lower compared to Ss-EPI DWI sequence (0.016±0.021 vs. 0.037±0.069，P=0.00). The inter-reader and intra-reader agreements for the assessment of qualitative parameters were good 〔0.74≤Kappa value or ICC≤0.92〕.Conclusion Rs-EPI DWI sequence is a potential technique to improve the imaging quality in the diagnosis of intracranial mass lesions.