Evaluation of the Cause of Internal Jugular Vein Obstruction on Head and Neck Contrast Enhanced 3D MR Angiography Using Contrast Enhanced Computed Tomography

ABSTRACT

PURPOSE: To evaluate the cause of internal jugular vein (IJV) obstruction on contrast enhanced 3D MR angiography (CE-MRA) using contrast enhanced computed tomography (CE-CT). MATERIALS AND METHODS: A total number of 30 patients were enrolled, who underwent both head and neck CE-MRA and CE-CT from 2005 to 2008. We defined obstruction group which had IJV obstruction and control group which had no IJV obstruction on CE-MRA. The following parameters were measured from axial images of CE-CT: 1) diameter of IJV; 2) distance between the styloid process and ipsilateral lateral mass of the atlas; 3) maximum area of lateral mass of the atlas. Each parameter was compared between obstruction group and control group. RESULTS: The diameter of IJV and distance between the styloid process and lateral mass of the atlas at IJV obstruction side in obstruction group were 1.6 +/- 1.0 mm and 4.1 +/- 2.1 mm respectively, which resulted in statistical significance (p<0.01). The maximum area of lateral mass of the atlas at IJV obstruction side in obstruction group was 103.4 +/- 25.3 mm2 which is significantly larger than in control group (p<0.05). CONCLUSION: We found that the cause of IJV obstruction on CE-MRA could be narrow space between the styloid process and the lateral mass of the atlas, which was related with asymmetric larger area of lateral mass of atlas.