Reithmeier Bianca, Laun Frederik B, Führes Tobit, Uder Michael, Bickelhaupt Sebastian, Saake Marc
Institut für Radiologie, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Deutschland.
Eur Radiol. 2025 Apr;35(4):2106-2115. doi: 10.1007/s00330-024-11063-1. Epub 2024 Sep 17.
The purpose of this study was to investigate the relevance of focal liver lesions (FLL) size for lesion detection comparing navigator triggering (TRIG) to free breathing (FB) liver Diffusion-weighted magnetic resonance imaging (DWI).
Patients with known or suspected FLL were prospectively (registry number 276_19 B) included from October to December 2019 in this study, out of which 32 had liver lesions. Echo planar spin-echo DWI data both with TRIG and FB were with approximately constant acquisition times acquired at 1.5 T. Lesions were segmented in the b = 800 s/mm² images in both the TRIG and FB images. The lesion size, location (liver segment), liver lesion visibility, as well as contrast-to-noise ratio (CNR) were recorded. The CNR was assessed with the Wilcoxon-Mann-Whitney test and the number of visible lesions with the Fisher test.
Data from 43 patients (22 female) were analyzed. The mean patient age was 58 ± 14 years. A total of 885 FLL (N) were segmented. Among these, 811 lesions (N) were detected with TRIG and FB, 65 lesions exclusively with TRIG (N), and nine exclusively in FB (N). The largest additional lesion in TRIG/FB had a diameter of 10.4 mm/7.6 mm. The number of additional lesions detected with TRIG decreased with size. Among all lesions ≤ 4.7 mm, the relative number of additional lesions was 15.6%. Additional lesions were found in all liver segments with TRIG. In the left liver lobe, the relative proportion was 9.2%, and in the right liver lobe 5.4%. CNR and visibility were significantly higher in TRIG than in FB (p < 0.001). In relation to size, the difference is significant in terms of visibility and CNR for lesion diameters ≤ 8 mm.
Respiration triggering can improve the detection of small liver lesions with diameters up to approx. 1 cm in the whole liver.
Question Can respiration triggering (TRIG) improve the detection of small FLL compared to FB diffusion-weighted imaging? Findings Among 885 segmented FLL, TRIG was superior to FB for lesions smaller than 8 mm and had improved CNR and visibility. Clinical relevance Diffusion-weighted magnetic resonance imaging is used for the detection of focal liver lesions and image quality is influenced by breathing motion. Navigator triggering becomes more important for smaller lesions, and seems recommendable for the detection of small focal liver lesions.
本研究旨在比较导航触发（TRIG）与自由呼吸（FB）肝脏扩散加权磁共振成像（DWI）时，局灶性肝病变（FLL）大小对病变检测的相关性。
2019年10月至12月前瞻性纳入（注册号276_19 B）本研究中已知或疑似患有FLL的患者，其中32例有肝脏病变。在1.5T下，采用近似恒定采集时间获取TRIG和FB的回波平面自旋回波DWI数据。在TRIG和FB图像的b = 800 s/mm²图像中对病变进行分割。记录病变大小、位置（肝段）、肝脏病变可见性以及对比噪声比（CNR）。采用Wilcoxon-Mann-Whitney检验评估CNR，采用Fisher检验评估可见病变数量。
分析了43例患者（22例女性）的数据。患者平均年龄为58±14岁。共分割出885个FLL（N）。其中，TRIG和FB检测到811个病变（N），仅TRIG检测到65个病变（N），仅FB检测到9个病变（N）。TRIG/FB中最大的额外病变直径为10.4mm/7.6mm。TRIG检测到的额外病变数量随大小而减少。在所有≤4.7mm的病变中，额外病变的相对数量为15.6%。TRIG在所有肝段均发现了额外病变。在左肝叶，相对比例为9.2%，在右肝叶为5.4%。TRIG的CNR和可见性显著高于FB（p < 0.001）。就大小而言，对于直径≤8mm的病变，在可见性和CNR方面差异显著。
呼吸触发可提高全肝直径达约1cm的小肝病变的检测率。
问题与FB扩散加权成像相比，呼吸触发（TRIG）能否提高小FLL的检测率？研究结果在885个分割的FLL中，对于小于8mm的病变，TRIG优于FB，且CNR和可见性有所改善。临床意义扩散加权磁共振成像用于检测局灶性肝病变，图像质量受呼吸运动影响。导航触发对较小病变更为重要，似乎推荐用于检测小局灶性肝病变。
