【摘要】 目的 探讨分段读出扩散加权成像（RESOLVE-DWI）序列在改善眼眶部几何失真伪影上的应用价值。方法 收集22例MR眼眶扫描的影像资料,包括T₂ WI,常规平面回波扩散加权成像（EPI-DWI）序列和RESOLVE-DWI序列。评估2组序列几何失真伪影的大小,观察视神经根的显示情况及表观扩散系数（ADC）值的差异。结果 相对于T₂ WI序列,EPI-DWI序列和RESOLVEDWI序列前后径的几何失真分别为4.11±2.9,1.58±1.03,横径的几何失真分别为1.62±1.12,1.03±0.88,RESOLVE-DWI序列在前后方向和横向的几何失真比EPI-DWI序列减小。EPI-DWI中16条视神经根无法清晰显示,而RESOLVE-DWI序列视神经根可全部清晰显示。测得EPI-DWI序列ADC值为（1.15±0.21）×10^-3 mm²/s,RESOLVE-DWI序列ADC值为（1.09±0.21）×10^-3 mm²/s,差别无意义（P=0.097>0.05）。结论 RESOLVE-DWI序列减小了眼眶部前后方向和横向上的几何失真,对视神经根的显示更加清晰且ADC值的测量值不受影响,可以替代EPI-DWI序列。更多还原

【Abstract】 Objective To study the value of readout segmentation of long variable echo-trains diffusion weighte imaging（RESOLVE-DWI）in the improvement of orbital geometric distortion artifacts.Methods Twenty-two cases of imaging data were collected including T2 WI,conventional EPI-DWI and RESOLVE-DWI.The geometric distortion artifacts and the number of orbital nerve roots on two DWI groups were evaluated.The ADC values of two DWI groups were calculated.Results The distortion of A-P direction was 4.11±2.9 on EPI-DWI and 1.58±1.03 on RESOLVE-DWI.The distortion of transverse direction was 1.62±1.12 on EPI-DWI and 1.03±0.88 on RESOLVE-DWI.The geometric distortion artifacts of RESOLVE-DWI on both directions were significantly lower than EPI-DWI.There were 16 optic nerves that could not be detected a valid ADC value on EPI-DWI,while all optic nerves were measured on the sequence of RESOLVE-DWI.The ADC value was（1.15±0.21） × 10^-3 mm²/s on EPI-DWI sequence and（1.09±0.21） ×10^-3 mm²/s on RESOLVE-DWI.There was no significant difference（P=0.097> 0.05）.Conclusion RESOLVE-DWI can reduce geometric distortion artifacts,which can also be used to show more optic nerve root on ADC maps with no difference from the ADC values obtained from EPI-DWI.Instead of EPI-DWI,RESOLVE-DWI can have great potential in MR orbital imaging.更多还原