Department for Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, Germany (P.G., G.G., D.P.).
Section on Experimental Radiology, University Hospital Tuebingen, Tuebingen, Germany (P.M.).
Acad Radiol. 2024 Mar;31(3):929-938. doi: 10.1016/j.acra.2023.08.013. Epub 2023 Sep 14.
To evaluate 4D Flow magnetic resonance imaging (MRI) sequences for quantitative flow measurements of the pelvic venous vasculature.
A prospective study of healthy volunteers was performed. After informed consent all subjects underwent 4D flow sequences at a 3 T MRI scanner with different isotropic resolution and different velocity encoding (Venc) settings: (sequence #1) voxel size (VS) 1.6 mm, Venc 50 cm/s; (sequence #2) VS 1.6 mm, Venc 100 cm/s and (sequence #3) VS 2.0 mm, Venc 50 cm/s. Perfusion parameters were calculated for all venous vessel segments starting at the level of the inferior vena cava and extending caudally to the level of the common femoral vein. For reference, arterial flow was calculated using 1.6 mm isotropic resolution with a Venc of 100 cm/s.
Ten healthy subjects (median age 28 years, interquartile range [IQR]: 26.25-28 years) were enrolled in this study. Median scanning time was 12:12 minutes (IQR 10:22-13:32 minutes) for sequence #1, 11:02 minutes (IQR 9:57-11:19 minutes) for sequence #2 and 6:10 minutes (IQR 5:44-6:47 minutes) for sequence #3. Flow measurements were derived from all sequences. The venous pelvic vasculature showed similar perfusion parameters compared to its arterial counterpart, for example the right common iliac arterial segment showed a perfusion of 8.32 ml/s (IQR: 6.94-10.68 ml/s) versus 7.29 ml/s (IQR: 4.70-8.90 ml/s) in the corresponding venous segment (P = 0.218). The venous flow measurements obtained from the three investigated sequences did not reveal significant differences.
4D Flow MRI is suitable for quantitative flow measurement of the venous pelvic vasculature. To reduce the scanning time without compromising quantitative results, the resolution can be decreased while increasing the Venc. This technique may be utilized in the future for the diagnosis and treatment response assessment of iliac vein compression syndromes.
评估 4D 磁共振成像（MRI）序列在骨盆静脉血管定量血流测量中的应用。
本研究为前瞻性研究，对所有自愿接受检查的健康志愿者进行了研究。所有志愿者均在 3T MRI 扫描仪上完成 4D 流动序列检查，采用不同的各向同性分辨率和不同的流速编码（Venc）设置：（序列 #1）体素大小（VS）为 1.6mm，Venc 为 50cm/s；（序列 #2）VS 为 1.6mm，Venc 为 100cm/s；（序列 #3）VS 为 2.0mm，Venc 为 50cm/s。从下腔静脉水平开始，对所有静脉血管段的灌注参数进行计算，并向尾侧延伸至股总静脉水平。作为参考，使用 1.6mm 各向同性分辨率和 100cm/s 的 Venc 计算动脉血流。
本研究共纳入 10 名健康志愿者（中位年龄 28 岁，四分位间距 [IQR]：26.25-28 岁）。序列 #1 的中位扫描时间为 12:12 分钟（IQR：10:22-13:32 分钟），序列 #2 为 11:02 分钟（IQR：9:57-11:19 分钟），序列 #3 为 6:10 分钟（IQR：5:44-6:47 分钟）。所有序列均可获得血流测量值。与动脉相比，骨盆静脉血管显示出相似的灌注参数，例如右侧髂总动脉段的灌注为 8.32ml/s（IQR：6.94-10.68ml/s），而相应静脉段为 7.29ml/s（IQR：4.70-8.90ml/s）（P=0.218）。三种研究序列的静脉血流测量值无显著差异。
4D 磁共振成像适用于骨盆静脉血管的定量血流测量。为了在不影响定量结果的情况下缩短扫描时间，可以在增加 Venc 的同时降低分辨率。该技术未来可能用于髂静脉压迫综合征的诊断和治疗反应评估。
