Verma Sachit K, Mitchell Donald G, Bergin Diane, Mehta Rashi, Chopra Sheetal, Choi Dongil
Department of Radiology, Thomas Jefferson University Hospital, 132 S 10th St, 1094 Main Bldg, Philadelphia, PA 19107, USA.
Radiology. 2007 Sep;244(3):791-6. doi: 10.1148/radiol.2443061518. Epub 2007 Jul 24.
To retrospectively evaluate cisterna chyli (CC) enhancement on magnetic resonance (MR) images obtained after intravenous administration of a gadolinium-based contrast agent.
This retrospective HIPAA-compliant study of 1.5-T MR imaging findings was institutional review board approved; informed patient consent was waived. All MR examinations involved the acquisition of heavily T2-weighted single-shot fast spin-echo (SSFSE) images and three-dimensional (3D) gradient-echo images obtained before and during the arterial, venous, and 3-5-minute delayed phases after intravenous bolus injection of gadopentetate dimeglumine. Included were the data of 59 patients (37 men, 22 women; mean age, 59 years) who had a CC 4 mm or greater in transverse diameter, which was identified as a tubular structure with fluid signal intensity (SI) on SSFSE images. The SI of the CC relative to the spinal canal (SC) was noted and was measured on 3D gradient-echo images obtained during all phases. The Student t test was performed for statistical evaluations.
Mean CC-SC SI ratios on nonenhanced, arterial phase, venous phase, and delayed phase images were 0.92, 0.98, 0.99, and 2.13, respectively. The CC had low SI on all 3D gradient-echo images obtained during the nonenhanced, arterial, and venous phases and high SI, similar to the azygos vein SI, on all delayed phase images. The CC-SC SI ratio during the delayed phase was significantly higher than that during the other phases (P<.001).
The CC has minimal or no enhancement on arterial phase and venous phase images but intense enhancement--similar to the enhancement of veins--on delayed phase images. Comparison of delayed phase images with SSFSE and venous phase images may help to distinguish the CC seen on delayed phase images from lymph nodes, the azygos vein, or esophageal varices.
回顾性评估静脉注射钆基对比剂后磁共振（MR）图像上乳糜池（CC）的强化情况。
这项符合健康保险流通与责任法案（HIPAA）的回顾性研究，涉及1.5-T MR成像结果，经机构审查委员会批准；患者知情同意书被豁免。所有MR检查均包括在静脉推注钆喷酸葡胺之前、动脉期、静脉期以及3至5分钟延迟期获取的重T2加权单次激发快速自旋回波（SSFSE）图像和三维（3D）梯度回波图像。纳入的是59例患者（37例男性，22例女性；平均年龄59岁）的数据，这些患者的CC横径为4 mm或更大，在SSFSE图像上被识别为具有液体信号强度（SI）的管状结构。记录CC相对于椎管（SC）的SI，并在所有期相获取的3D梯度回波图像上进行测量。采用Student t检验进行统计学评估。
非强化期、动脉期、静脉期和延迟期图像上CC-SC SI比值分别为0.92、0.98、0.99和2.13。在非强化期、动脉期和静脉期获取的所有3D梯度回波图像上，CC的SI均较低，而在所有延迟期图像上，CC的SI较高，与奇静脉SI相似。延迟期的CC-SC SI比值显著高于其他期相（P<0.001）。
CC在动脉期和静脉期图像上强化极少或无强化，但在延迟期图像上强化明显——类似于静脉的强化。将延迟期图像与SSFSE和静脉期图像进行比较，可能有助于区分延迟期图像上所见的CC与淋巴结（结）、奇静脉或食管静脉曲张。
