Image Quality and Detection of Small Focal Liver Lesions in Diffusion-Weighted Imaging Comparison of Navigator Tracking and Free-Breathing Acquisition
Image Quality and Detection of Small Focal Liver Lesions in Diffusion-Weighted Imaging Comparison of Navigator Tracking and Free-Breathing Acquisition
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DOI：
10.1097/rli.0000000000000776
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发表时间：
2021-09-01
影响因子：
6.7
通讯作者：
Laun, Frederik B.
中科院分区：
文献类型：
--
作者：
Saake, Marc;Seuss, Hannes;Laun, Frederik B.
目的本研究的目的是比较自由呼吸（FB）与导航触发（NT）获得的肝脏个体内弥散加权成像（DWI）评估非酒精性肝病患者的肝脏局灶性小病变（FLL）。材料与方法前瞻性纳入已知或疑似多发FLL的患者，并进行NT和FB采集的自旋回波平面DWI（b值，50和800 s/mm（2）[b50和b800]）。使用具有相似采集时间的NT和FB DWI序列。在b800测量肝脏和病变信噪比。DWI扫描由2名阅片师独立分析。采用5分Likert量表对肝脏边缘描绘、阶梯状伪影的存在、血管清晰度、心脏运动伪影的严重程度、总体图像质量和病变显著性进行评级。分别对小型和大型FLL（即，≥ 1 cm）的病变显著性进行评级。通过比较FB与NT可见的病变数量来估计FLL的可检测性。结果43例患者纳入研究。FB采集在心脏运动伪影的严重程度方面表现更好。NT在肝脏边缘描绘和血管清晰度方面表现更好。阶梯伪影、整体图像质量和大FLL的明显性差异不大，而小FLL的明显性对于NT更好。对于小FLL，两名阅片者在b800时发现11例病例中有更多NT病变。对于大FLL，这种影响不太明显（1名阅片人报告了1例b800病例）。NT/FB的平均肝脏和病变信噪比分别为16.8/41.5和19.8/38.4。结论NT对小FLL的检出率较高。FB和NT的大FLL检测同样良好。我们认为应该使用NT。
Objectives The aim of this study was to compare intraindividual diffusion-weighted imaging (DWI) of the liver acquired with free breathing (FB) versus navigator triggering (NT) for assessing small focal liver lesions (FLLs) in noncirrhotic patients. Materials and Methods Patients with known or suspected multiple FLLs were prospectively included, and spin-echo echo-planar DWI with NT and FB acquisition was performed (b-values, 50 and 800 s/mm(2) [b50 and b800]). NT and FB DWI sequences with similar acquisitions times were used. Liver and lesion signal-to-noise ratios were measured at b800. The DWI scans were analyzed independently by 2 readers. Liver edge delineation, presence of stair-step artifacts, vessel sharpness, severity of cardiac motion artifacts, overall image quality, and lesion conspicuity were rated with 5-point Likert scales. Small and large FLLs (ie, = 1 cm) were rated separately for lesion conspicuity. The FLL detectability was estimated by comparing the number of lesions visible with FB to those visible with NT. Results Forty-three patients were included in the study. The FB acquisition performed better in terms of severity of cardiac motion artifacts. The NT performed better in terms of liver edge delineation and vessel sharpness. Little difference was found for stair-step artifact, overall image quality, and conspicuity of large FLL, whereas the conspicuity of small FLL was better for NT. For small FLL, both readers found more lesions with NT in 11 cases at b800. For large FLL, this effect was much less pronounced (1 case at b800 reported by 1 of the readers). The mean liver and lesion signal-to-noise ratios were 16.8/41.5 and 19.8/38.4 for NT/FB, respectively. Conclusions Small FLL detection is better with NT. Large FLL detection by FB and NT is similarly good. We conclude that NT should be used.