Imaging of Cisterna Chyli and Thoracic Duct by Nonenhanced MR Lymphography / 中国普外基础与临床杂志

ABSTRACT

Objective To investigate the depiction rate of normal cisterna chyli and thoracic duct by nonenhanced MR lymphography and to describe their appearances on MR imaging.Methods Special MR hydrography sequence was added to the MR imaging protocols of 112 patients undergoing MR examination of the thorax and upper abdomen.MR imaging sequences included①Respiratory-gated HASTE T2W sequence;②Breath-hold FLASH T1W sequence;③Respiratory-gated TSE 3D T2W sequence(3D MR hydrography sequence)in coronal plane.One hundred cases who met the inclusion criteria were included into the study for observation of the depiction rate,location and morphology of cisterna chyli and thoracic duct.Results On TSE 3D T2W imaging①Cisterna chyli was visualized in 71/100(depiction rate 71.0%),morphologically including single-tube type 43.7%(31/71),bifurcation type(2-3 tubes)23.9%(17/71),plexus type 32.4%(23/71).Average length of the cisterna chyli was 4.5 cm.②The depiction rate of the lower segment of thoracic duct was 57.0%(57/100),average ductal diameter was 0.23 cm.③The depiction rate of upper segment of the thoracic duct was 31.0%(31/100).Conclusion As a noninvasive method for depicting the lymphatic system,nonenhaced MR lymphography(TSE 3D T2W sequence)demonstrated a high depiction rate for cisterna chyli and lower thoracic duct.Combined with axial images of HASTE and FLASH sequences,the location and morphology of these larger lymphatic ducts can be defined.