Bastian-Jordan Matthew, Dhupelia Sanjay, McMeniman Morgan, Lanham Matthew, Hislop-Jambrich Jacqueline
QLD X-ray, QEII Hospital, Coopers Plains, Brisbane, Queensland, Australia.
University of Queensland, Brisbane, Queensland, Australia.
J Med Radiat Sci. 2019 Sep;66(3):163-169. doi: 10.1002/jmrs.350. Epub 2019 Jul 29.
The objective of this study was to evaluate the effect on diagnostic image quality and acquisition time utilising a DIXON sequence to replace two standard proton density (PD) fat saturation (FS) sequences in routine magnetic resonance (MR) evaluation of the knee.
Thirty-one consecutive patients referred for an MR examination of the knee were examined using the routine departmental protocol along with the addition of a DIXON sequence. The sequences were all evaluated by a senior radiologist and feedback provided via both written and scored responses. The sequences were then repackaged for two additional reviewers with the sagittal PD FS (Chemical Shift Selective Fat Saturation or CHESS) and sagittal PD removed and replaced with the DIXON (fat suppressed and in-phase, respectively) sequence equivalents. Scored and written responses were tabled and reviewed to assess the suitability of sequence replacement.
The DIXON-based images were judged as being comparable replacements for the sagittal PD fat sat and PD sequences. There was no report of any loss in diagnostic confidence across the 31 patients (total of 32 knees) with a time saving of just over 10% gained. The most common issues raised affecting image quality, though not affecting diagnostic attributes, were patient motion and a minor chemical shift artefact.
The use of the DIXON technique in place of the PD sequences was of equivalent diagnostic quality with'good' to 'outstanding' fat suppression observed for the majority of cases using the DIXON sequence with an incremental time saving obtained.
本研究的目的是评估在膝关节常规磁共振（MR）检查中，使用狄克逊（DIXON）序列替代两个标准质子密度（PD）脂肪抑制（FS）序列对诊断图像质量和采集时间的影响。
31例连续接受膝关节MR检查的患者按照科室常规方案进行检查，并额外增加了一个DIXON序列。所有序列均由一位资深放射科医生进行评估，并通过书面和评分回复提供反馈。然后将序列重新打包，供另外两位审阅者使用，矢状面PD FS（化学位移选择性脂肪抑制或CHESS）和矢状面PD被移除，分别用DIXON（脂肪抑制和同相位）序列等效物替代。将评分和书面回复制成表格并进行审查，以评估序列替代的适用性。
基于DIXON的图像被判定为矢状面PD脂肪抑制和PD序列的可比替代物。在3个月内，没有任何关于这31例患者（共32个膝关节）诊断信心丧失的报告，并且节省了10%以上的时间。影响图像质量但不影响诊断属性的最常见问题是患者运动和轻微的化学位移伪影。
使用DIXON技术替代PD序列具有同等的诊断质量，在大多数使用DIXON序列的病例中观察到“良好”至“出色”的脂肪抑制效果，同时还节省了时间。
