Depiction of the Petrosal Vein Complex with 3D-MR-Venography

Objective: Petrosal vein occlusion may be well tolerated, but sometimes it causes deleterious consequences. It would be crucial identifying the subgroup of patients who does not tolerate the occlusion. Design: Aim of this study was to depict the petrosal vein, main branches and anastomoses with a high-resolution, contrast-medium enhanced 3D-GRE-MR-venography (CE-3D-MRV). Patients/Methods: Total 20 patients (40 sides) were examined with a 3D-GRE-sequence at the 3 T MRT (Skyra, Siemens) with the following parameters: repetition time 7.96 ms, echo time 2.53 ms, flip angel 25 degrees, band 130Hz/pixel, FOV 254×280 mm², matrix 640×640, slice thickness 0.625 mm, voxel 0.5×0.5×0.625 mm³, acquisition time 2.04 min. Two radiologists identified and measured independently the veins, their diameters, and anastomoses (PACS, General Electrics). Results: In all patients we identified a vena petrosa (1VP/case = 50%, 2VP/case = 42%, 3VP/case = 8%) and assigned the contributaries (63% vena cerebelli superior, 63% vena fissura cerebellopontina, 56% vena pontina transversa, 10% vena mesencephalica lateralis). In 85% of the cases we identified relevant anastomoses between the respective petrosal veins or to the supratentorial territory. The mean diameter of the petrosal veins was 2.3±?1.0 mm (range, 0.5-5.1 mm). Conclusion: The CE-3D-MRV gives an excellent image of the petrosal vein system and thus seems to offer the possibility to identify preoperatively patients with lack of sufficient anastomoses.