RESOLVE-DWI在直肠MRI检查中的临床应用研究

A Study of the Clinical Application of the Readout Segmentation of Long Variable Echo-Trains Diffusion Weighted Imaging in Rectal MRI

目的探讨分段读出平面回波扩散加权成像（RESOLVE-DWI）在1.5 T场强下直肠MRI检查中的临床应用价值。方法 35例因病情需要拟行直肠MRI检查的患者,进行常规直肠MRI扫描的同时,扫描RESOVLE-DWI序列与常规DWI序列。由2名放射科诊断医师按Likert 5分法对两组DWI的图像质量进行主观评价,评价内容包括图像的解剖变形、空间分辨率、病灶细节显示及总体图像质量。定量测量并计算两组DWI图像的信噪比（SNR）、对比噪声比（CNR）、对比度（C）及表观扩散系数（ADC）值以进行客观评价。2名阅片医师的一致性采用Kappa检验,两组DWI的主观评价各项指标均采用两两比较秩和检验,客观评价各项指标均采用配对样本t检验。结果 RESOLVE-DWI与常规DWI在图像质量4项指标及SNR、CNR对比上差异均具有统计学意义（P均〈0.05）。结论 RESOLVE-DWI对比常规DWI提升了图像质量,明显提升了图像SNR与CNR,对ADC值的测量没有影响,可以替代常规DWI用于直肠MRI扫描。

Objective The aim of the work is to investigate the clinical value of the readout segmentation of long variable echo-trains diffusion weighted imaging（ RESOLVE-DWI） in the rectal MRI at 1.5T field strength. Methods Prospectively collected patients whose condition required an MRI rectal examination in 35 cases. When scanning routine conventional MRI sequences,adding the RESOLVE-DWI sequence were link with the conventional DWI sequence in order to maintain the same parameters. Two radiologists analysed the anatomic distortion,image sharpness,lesion conspicuity and overall image quality in accordance with the Likert 5 points. The SNR,CNR,C and ADC values of two DWI images were quantitatively measured and evaluated for objective evaluation. The consistency of the two reading physicians using kappa test,two groups of DWI subjective evaluation of the indicators used two pairs of rank and test,the objective evaluation of the indicators are used to match the sample t test. Results The RESOLVE-DWI and conventional DWI show statistical differences in four indexes of diagnotic efficiency,the SNR,the CNR and the C（ P values meet P〈0. 05）. Two review physicians considered that 91. 4% and 94. 2% of patients＇ RESOLVE-DWI images were more conducive to diagnosis. RESOLVE-DWI compared to conventional DWI in the image SNR,CNR has greatly improved. The ADC values have no significant statistical differences（ P values meet P〉0. 05）. Conclusion The RESOLVE-DWI can improve quality of the image,significantly improve the image SNR and CNR,and have no effect on the ADC values. Thus it can replace the conventional DWI for rectal MRI scans.